which pedal do u think is the best for compression?
these are my options:
dod 280
ibanez cp9
mxr dynacomp
ross compressor
orange squeezer
i cant decide which pedal to clone.any ideas?
Those are all decent pedals. So, what do you want from a compressor? Versatility? An easy build? High attack? Low attack? Transparency? Give us a few more details. Also, I'd suggest breadboarding these to see what you think of them.
!
I like this one:
http://www.sugardas.lt/~igoramps/article60.html
No need to tune after building - it works immediately, if built without mistakes, it is very versatile and suits for guitar and bass-guitar no matter what pickups are installed - passive or active. The second schematics is easier to build, 'cause it uses Jfets of one type (J201 without any mathing), opamp is LM324 The only trouble is twin jfet KP504HT3B, but it can be replaced with a matched pair of J271, 2N5461, 2N5462, J175, J174, 2N5115.
Forgot one thing: lm324 must be turned on 1800, Check datasheet.
That looks like a fancy circuit, Zapp !
An interesting alternative to be sure, kudos for venturing into what looks like extensive entry-board to try it out !
Word association/abbreviation:
dod 280 Lights LED?/Photocell R changes. Simple, may let in blip of attack cause the photocell goes X fast, mods/function is 'open face', easy-ish to fiddle with, if strong/less than transparent, useful sound.
ibanez cp9
Ibanez, reviewed, would like to try one.
mxr dynacompross compressor
Venerable, powerful can do 'hard comp'.
orange squeezer
Has 1 knob for volume, can do 1 slick trick with peak supression, very stable and shallow gain ramps, may sound just like very nice booster, high speed light-transparent compression.
Ramp rates and control [varies as stated.
Distortion {OS has teeny bit of sweet dirt in it, the DOD attack-slip-blip lends itself to attack of harmonic-wall [requires post distortion] also called 'clunky's-cool'.
The Dyna/Ross is good demonstration of voicing compressors, since they're nearly identical and: adjustable to strong = boosts low signal...the LP filtering comparison between these two is interesting study and choice.
So we're talking about alteration of the dynamics right off the guitar here.
All that said...letting the compressor have you find the sound as opposed to you finding the sound of the compressor is a suggested approach [especially useful for hard, slow comp sounds].
One dude had a reverse attack thing...and played that sound the entire time, transforming the guitar from a percussive instrument that could add an accent to the top of a beat...lotta help that was to rythm knot, the novelty wore off after the first few measures.
My favourite compressor is by far the carl martin compressor limiter.
It is a studio-quality effect, absolutely trasparent and versatile going from strongly compressed tones to subtle effect with great sustain.
And the schematic is known...
http://freestompboxes.org/viewtopic.php?f=13&t=9287 (http://freestompboxes.org/viewtopic.php?f=13&t=9287) ;D
CP9, Dynacomp, and Ross all belong to the same family. CP9 uses a slightly better (and certainly more available) chip, but you have to figure out whether you want the solid-state switching or not. CP9 uses the variable recovery feature (Attack), but that is easily implemented in the MXR and Ross too.
The DOD is optical, which has a slightly different feel, and holds the promise of being potentially cleaner than OTA or FET-based.
The OS, when stock, behaves a little more like a limiter than a compressor, which those who like to pick fast are partial to.
Quote from: Zapp Brannigan on February 09, 2011, 08:12:11 AM
I like this one:
http://www.sugardas.lt/~igoramps/article60.html
No need to tune after building - it works immediately, if built without mistakes, it is very versatile and suits for guitar and bass-guitar no matter what pickups are installed - passive or active. The second schematics is easier to build, 'cause it uses Jfets of one type (J201 without any mathing), opamp is LM324 The only trouble is twin jfet KP504HT3B, but it can be replaced with a matched pair of J271, 2N5461, 2N5462, J175, J174, 2N5115.
Forgot one thing: lm324 must be turned on 1800, Check datasheet.
wow nice!
Here's mine. Studio quality, full bandwidth, handles signals up to line level, modular so it is easily tweakable, probably lower noise and distortion than the Carl Martin, too. However, it does require an oscilloscope (or good ears) to set up the bias.
(http://i81.photobucket.com/albums/j207/merlinblencowe/Compressor/CompressorSchem.jpg)
The purpose of the U1b stage puzzles me. I'm not dissing it. I'm just puzzled by why something that looks like a soft limiter is placed ahead of the rectifier stage....or is there some subtle detail I'm missing in either the functioning of that stage or some higher-order strategy on your part to achieve the right feel.
Note that it would not be the first time I've misunderstood a circuit because the way it was drawn was different than what I had in mind.
The Orange Squeezer has a very light tube-ish overdrive that works great with single coils.
Quote from: Mark Hammer on February 09, 2011, 08:56:28 PM
The purpose of the U1b stage puzzles me. I'm just puzzled by why something that looks like a soft limiter is placed ahead of the rectifier stage....or is there some subtle detail I'm missing in either the functioning of that stage or some higher-order strategy on your part to achieve the right feel.
It's a pseudo-logarithmic amplifier! It conditions the signal prior to rectification. Because of the non-linear characteristics of the FET I found it necessary to add the log amp so as to get a soft knee on the compression characteristic. Actually it does more than one job: it provides gain so the threshold can be adjusted, shapes the control signal, prevents large negative swings hitting the rectifier (which would otherwise cause it to hit the rail and invert, which is something TL07x opamps do), and it provides a convenient way to filter the control signal if desired- hence the treb/bass/normal switch.
Thanks for that. Much appreciated.
Obviously a much more thoughtfully designed device than a quick glance might have sugegsted! All of which merits a tip of the hat. :icon_biggrin:
A tip of the hat indeed!
Well done.
It has real attack, release, threshold, and ratio controls! And a soft knee. Rare in the guitar compressor pedal world. Thanks for sharing your design!
the ones i listed above are my only choices since i already have the layouts for them..
but if you were to rank them, which would come first?
but if you were to rank them, which would come first? Dod 280 Would be..My
#1 Cobblecomp.
Ibanez cp9 My #1 Comp I have least exp./knowledge of, it's of Ibanez design release
- .
Mxr dynacomp #1 hands down, requires CA3080 and requires more parts than the Ibanez?
Ross compressor is #1 when the DYNA circuit tames the highs more than desired, and it's ''compressor-compromises'' otherwise fits player preferences.
Orange Squeezer is outstanding for it's lack of control features:
#1 for least adjustable compression control.
Quote from: merlinb on February 10, 2011, 06:50:50 AM
Quote from: Mark Hammer on February 09, 2011, 08:56:28 PM
The purpose of the U1b stage puzzles me. I'm just puzzled by why something that looks like a soft limiter is placed ahead of the rectifier stage....or is there some subtle detail I'm missing in either the functioning of that stage or some higher-order strategy on your part to achieve the right feel.
It's a pseudo-logarithmic amplifier! It conditions the signal prior to rectification. Because of the non-linear characteristics of the FET I found it necessary to add the log amp so as to get a soft knee on the compression characteristic. Actually it does more than one job: it provides gain so the threshold can be adjusted, shapes the control signal, prevents large negative swings hitting the rectifier (which would otherwise cause it to hit the rail and invert, which is something TL07x opamps do), and it provides a convenient way to filter the control signal if desired- hence the treb/bass/normal switch.
Merlin, that compressor is
SLICK!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! :icon_mrgreen:
Any chance of hearing a sound clip or two?
Quote from: merlinb on February 09, 2011, 03:59:18 PM
Here's mine. Studio quality, full bandwidth, handles signals up to line level, modular so it is easily tweakable, probably lower noise and distortion than the Carl Martin, too. However, it does require an oscilloscope (or good ears) to set up the bias.
(http://i81.photobucket.com/albums/j207/merlinblencowe/Compressor/CompressorSchem.jpg)
Well, I
do have an oscilloscope, so if you want to tell us more about it...
:icon_mrgreen:
How should it be biased?
I own a Dynacomp, Orange Squeezer, and a DOD.
My personal favorite is the Orange Squeezer. It warms up the sound a bit and squishes it in a very reactively pleasant manner that works beautifully with clean, whether it be plucking with fingers, using a slide or using a pick. It sounds nice on pedal steel as well. Works great on all pick ups. It doesn't seem to play well with overdrives though, IMHO. It's a fun sounding compressor though that you definitely can hear working when it is on.
Dynacomp sounds like the inbetween of the DOD and the Squeezer. It has a nice squish, but doesn't overly color the tone. Not totally transparent, but not warm like the OS either. It has a fairly fast attack and a long release that is similar to the OS. It works better before an overdrive than the OS due to the limited tonal coloration. I've used it on a number of recordings, but it is never my first choice in any situation.
The DOD is very transparent and is what is currently on my effect board. I just leave it on all the time for live. It is definitely the "Can't tell if it's even on until I turn it off" compressor of the bunch. Works very well in conjunction with other pedals.
If I had the room, I'd put both the orange squeezer and DOD on my pedal board because there are times where I wish I had the OS for clean parts. But for me because I use a lot of overdrive and I want to control the overall dynamics of my playing all the time, the DOD wins.
Quote from: Morocotopo on February 11, 2011, 03:06:33 PM
Well, I do have an oscilloscope, so if you want to tell us more about it...
How should it be biased?
Fair enough! You need to disable the side chain so the FET can be manually controlled.
Easiest way is to short the 100k feedback resistor on U1b.
Set postgain to zero resistance.
Set ratio to zero resistance.
Input a suitable test tone; level is not important provided it doesn't clip. Say, 100mVpk, 1kHz, ish.
Monitor the input and output waves and adjust the bias until the output amplitude is equal to the input.
That's it! For anyone without a scope they'd have to switch back and forth between the effect and bypass, and adjust the bias by ear for equal loudness.
I will try and make a sound clip this weekend.
The MXR Sustain Unit is more interesting than the Dynacomp and its derivates. But I couldn´t find a schematic for it. Someone just started a retracing thread over at the other forum...
That would be my first choice for a strong, audible sustain effect.
For decent sound improvement, esp for clean sounds, I really like the Demeter Compulator (see: Baja Compulator). Or have a look at Bajamans Optical Limiter.
Quote from: thedefog on February 11, 2011, 03:32:00 PM
I own a Dynacomp, Orange Squeezer, and a DOD.
My personal favorite is the Orange Squeezer. It warms up the sound a bit and squishes it in a very reactively pleasant manner that works beautifully with clean, whether it be plucking with fingers, using a slide or using a pick. It sounds nice on pedal steel as well. Works great on all pick ups. It doesn't seem to play well with overdrives though, IMHO. It's a fun sounding compressor though that you definitely can hear working when it is on.
Dynacomp sounds like the inbetween of the DOD and the Squeezer. It has a nice squish, but doesn't overly color the tone. Not totally transparent, but not warm like the OS either. It has a fairly fast attack and a long release that is similar to the OS. It works better before an overdrive than the OS due to the limited tonal coloration. I've used it on a number of recordings, but it is never my first choice in any situation.
The DOD is very transparent and is what is currently on my effect board. I just leave it on all the time for live. It is definitely the "Can't tell if it's even on until I turn it off" compressor of the bunch. Works very well in conjunction with other pedals.
If I had the room, I'd put both the orange squeezer and DOD on my pedal board because there are times where I wish I had the OS for clean parts. But for me because I use a lot of overdrive and I want to control the overall dynamics of my playing all the time, the DOD wins.
OS not good for distortion??
Quote from: FlyingZ on February 09, 2011, 09:03:30 PM
The Orange Squeezer has a very light tube-ish overdrive that works great with single coils.
I think the same, it's quite clean, but yo better place 2 pots (I think vol and compression), and use a high gain JFET as a j201 or a 2sk117. Also you could try the DOD 280. They are the simplest!
Quote from: FlyingZ on February 15, 2011, 05:39:10 AM
Quote from: mr_deadmaxxx on February 15, 2011, 03:00:06 AM
OS not good for distortion??
I thought the same :D
I find it makes my overdrive/distortion pedals too farty/boomy on the low end and that the individual note playing is a little on the muddy side for my tastes. That's using a Alnico 2 pro bridge humbucker in a telecaster going into a 68 twin reverb.
I suppose when deciding on a build you should read some reviews, try out some in shops, and match your needs and expectations to a pedal. That way you're ound to get close to what you want on the first try.
For me there are kinda 2 types of compression.
First is one thats very sustained, very "squishy", and fattens up the tone i.e. dims the highs and adds balls (not really an expectation from compression I know but useful none the less). It has a pronounced sonic "effect", like the Dyna sound byte on the dunlop site. Personally I associate these squished sounds best clean/jangly tones and chording. If used on a high gain pedal/am channel, I find it cuts too much out of the sound as others have stated.
If this is what your after, I would go for a Dynacomp, Ross or Orange Squeezer.
The other compression I use is more for "feel" than sound if that makes any sense. (Alike many others) I have a comp on all the time. Sustain is set very low - just so you can barely hear the "wall" kick in when you really attack the strings (apologies - cant think how to describe it but hopefully you know what I mean). Volume I set just above unity. I find it evens out the sound and balances out the difference in string volumes etc, especially when I switch from pick to fingers and am playing on the higher strings/higher registers. Im not sure compressors are design to balance out levels across the strings, but it works for me!! These "transparent" compressors translate to distorted and clean base sounds.
For these senarios I would go with a Compulator, Philsophers Stone, Ibanez CP9, Boss CS2/3 or Marshall ED-1 (I hear these are pretty good provided you get one which will last).
My personal favorite is a DOD Milk Box. Its not an popular choice but they are FANTASTIC boxes. You can still buy the odd one for £50. Not sure they still make them.
I believe it shares the same typology as the CS2, CP9 (therefore Ross/Dyna to some extent), however, it covers a lot of ground. It can do the transparent thing, and the effected squishy sounds also. I've also had recent success with a Compulator clone built from a project at f r e e s t o m p b o x e s. This is great great great natrual sounding and versatile optical compressor.
My $0.02, or pence as im in UK.
Ry
Quote from: ryanuk on February 15, 2011, 11:53:15 AM
For me there are kinda 2 types of compression.
First is one thats very sustained, very "squishy", and fattens up the tone i.e. dims the highs and adds balls (not really an expectation from compression I know but useful none the less). It has a pronounced sonic "effect", like the Dyna sound byte on the dunlop site. Personally I associate these squished sounds best clean/jangly tones and chording. If used on a high gain pedal/am channel, I find it cuts too much out of the sound as others have stated.
If this is what your after, I would go for a Dynacomp, Ross or Orange Squeezer.
The other compression I use is more for "feel" than sound if that makes any sense. (Alike many others) I have a comp on all the time. Sustain is set very low - just so you can barely hear the "wall" kick in when you really attack the strings (apologies - cant think how to describe it but hopefully you know what I mean). Volume I set just above unity. I find it evens out the sound and balances out the difference in string volumes etc, especially when I switch from pick to fingers and am playing on the higher strings/higher registers. Im not sure compressors are design to balance out levels across the strings, but it works for me!! These "transparent" compressors translate to distorted and clean base sounds.
For these senarios I would go with a Compulator, Philsophers Stone, Ibanez CP9, Boss CS2/3 or Marshall ED-1 (I hear these are pretty good provided you get one which will last).
I completely agree on this distinction.
This also explains why I like the Carl Martin: is the only one I found good for both.
Quote from: thedefog on February 15, 2011, 10:03:10 AM
Quote from: FlyingZ on February 15, 2011, 05:39:10 AM
Quote from: mr_deadmaxxx on February 15, 2011, 03:00:06 AM
OS not good for distortion??
I thought the same :D
I find it makes my overdrive/distortion pedals too farty/boomy on the low end and that the individual note playing is a little on the muddy side for my tastes. That's using a Alnico 2 pro bridge humbucker in a telecaster going into a 68 twin reverb.
It's the only one I can use with distortion albeit not too often. Just goes to show the many variations in guitar amp combos.
Some very good comments here.
I think the biggest challenge in producing a "good" guitar compressor sound is that the full bandwidth of the guitar is not equally represented across the lifespan of any picked note or strummed chord. Most of the treble content is packed into that initial transient that gets pushed down hard, while the content that gets brought back in over time is largely low end. Were it the case that the spectral content were constant, then you could imagine how to set the various controls that shape the rectification and control signal. But even if you have an Attack and Release control (and this is not to take anything away from merlinB's excellent design), the Release is addressing different spectral content than the Attack is.
That's not an insurmountable obstacle, but it IS a tough one for all single-band guitar compressors to grapple with.
The best compressor for me is NO compressor. :icon_wink:
I hear ya, but I will also affirm that, over the years, some of my very best and most luscious and fascinating guitar tones have relied on compression.
Quote from: Mark Hammer on February 15, 2011, 03:17:57 PM
I hear ya, but I will also affirm that, over the years, some of my very best and most luscious and fascinating guitar tones have relied on compression.
I like natural compression from tubes. Whenever I use a compressor pedal, I feel like I am driving a vehicle with a governor on it that takes all the power out of the vehicle. It dampens all the dynamics in my playing. :icon_cry:
I will say that of the ones I have built/used, I think I like the Orange Squeezer best because it's kind of a subtle effect compared to my Boss pedal which is like throwing a wet blanket on a fire. :icon_lol:
Depends how you want to think of "dynamics". For instance, I like being able to modulate the sound of the guitar, and how the tone varies with pick attack, without having to have robust volume changes come along for the ride. Not every single time, to be sure, but at least sometimes. There is a reason why folks who like to play a clean-as-a-whistle Tele love compressors. You can get that snap off the bridge without distracting people by an ice-pick through the forehead from the amp.
Will too much compression destroy one's capacity to elicit qualitatively different overdrive tones, via pick attack, whether from an amp or pedal? You betcha. But like I say, that's not the only cotext where you might want to use one.
I think they're great for being able to go crazy on rhythm guitar without accidentally over-shadowing a singer.
It would actually be kinda neat to be able to use one foot-pedal to vary both compression and output level simultaneously. That is, pull pack and the amount of compression increases but the output level is decreased, so you're "there" in the background, but you don't get lost. Then when solo time approaches, you treadle forward and the dynamics get gradually restored as the volume gets upped.
Quote from: Mark Hammer on February 15, 2011, 04:31:46 PM
Depends how you want to think of "dynamics". For instance, I like being able to modulate the sound of the guitar, and how the tone varies with pick attack, without having to have robust volume changes come along for the ride. Not every single time, to be sure, but at least sometimes. There is a reason why folks who like to play a clean-as-a-whistle Tele love compressors. You can get that snap off the bridge without distracting people by an ice-pick through the forehead from the amp.
Yeah, they have their uses. I see a compressor as a limiter. I use a volume pedal to control my output level and am very sensitive to how loud I am in comparison to everything else and have been doing this for at least ten years now, so I'm quite used to it. So in that way, I am my own compressor, without any limiting or loss of dynamics in my playing. :icon_wink:
Quote from: Mark Hammer on February 15, 2011, 12:57:24 PM
Some very good comments here.
I think the biggest challenge in producing a "good" guitar compressor sound is that the full bandwidth of the guitar is not equally represented across the lifespan of any picked note or strummed chord. Most of the treble content is packed into that initial transient that gets pushed down hard, while the content that gets brought back in over time is largely low end. Were it the case that the spectral content were constant, then you could imagine how to set the various controls that shape the rectification and control signal. But even if you have an Attack and Release control (and this is not to take anything away from merlinB's excellent design), the Release is addressing different spectral content than the Attack is.
That's not an insurmountable obstacle, but it IS a tough one for all single-band guitar compressors to grapple with.
I find with my OS, if I lower my guitar volume a touch - and I have a treble bleed cap - it brightens up considerably. It's kinda counterintuitive though, if you want to cut through more and have more presence, you have to turn down a bit.
Sorta like getting your best, crispest clean sound by turning on a fuzz pedal :)
merlin, I was wondering if your ratio pot acted kind of like a blend control in between the effected signal and the clean signal.
I made a Ross comp a while back, and had to add a blend control to it to get back some of my highs. Have you heard a Ross comp, and would you be able to make any tonal distinctions between the two?
Thanks
Quote from: merlinb on February 11, 2011, 04:07:09 PM
Quote from: Morocotopo on February 11, 2011, 03:06:33 PM
Well, I do have an oscilloscope, so if you want to tell us more about it...
How should it be biased?
Fair enough! You need to disable the side chain so the FET can be manually controlled.
Easiest way is to short the 100k feedback resistor on U1b.
Set postgain to zero resistance.
Set ratio to zero resistance.
Input a suitable test tone; level is not important provided it doesn't clip. Say, 100mVpk, 1kHz, ish.
Monitor the input and output waves and adjust the bias until the output amplitude is equal to the input.
That's it! For anyone without a scope they'd have to switch back and forth between the effect and bypass, and adjust the bias by ear for equal loudness.
I will try and make a sound clip this weekend.
Hey Merlib I don't have any J112 FETs so what other common FETs would work well in this circuit?
Mass on a spring compression...speaker !
Pneumatic compression...the Enclosure !
These two can be made so they work together and provide very compression.
Quote from: auden100 on February 17, 2011, 06:44:11 PM
merlin, I was wondering if your ratio pot acted kind of like a blend control in between the effected signal and the clean signal.
Not really. It simply reduces the amount by which the signal is attenuated when the FET turns on.
Quote
I made a Ross comp a while back, and had to add a blend control to it to get back some of my highs. Have you heard a Ross comp, and would you be able to make any tonal distinctions between the two?
Sorry, I've never heard that pedal in person. My circuit is deliberately designed to be low distortion and wide bandwidth, because I wanted it to be suitable for bass/keyboard/voice etc ('universal'). Maybe the Ross is meant to be a bit more 'coloured' and 'guitar specific'?
Quote
Merlib I don't have any J112 FETs so what other common FETs would work well in this circuit?
Anything with an average Vgs(off) of less than 3V. J113 and 2SK30A should work. Be prepared to try more than one sample though, whatever kind of FET you use.
Quote from: merlinb on February 11, 2011, 04:07:09 PM
Quote from: Morocotopo on February 11, 2011, 03:06:33 PM
Well, I do have an oscilloscope, so if you want to tell us more about it...
How should it be biased?
Fair enough! You need to disable the side chain so the FET can be manually controlled.
Easiest way is to short the 100k feedback resistor on U1b.
Set postgain to zero resistance.
Set ratio to zero resistance.
Input a suitable test tone; level is not important provided it doesn't clip. Say, 100mVpk, 1kHz, ish.
Monitor the input and output waves and adjust the bias until the output amplitude is equal to the input.
That's it! For anyone without a scope they'd have to switch back and forth between the effect and bypass, and adjust the bias by ear for equal loudness.
I will try and make a sound clip this weekend.
Using a boutique mindset...
Could you just make it a pot and call it a feature? ("volume"?)
i think i have decided to go with an Ibanez CP9..is this a good compressor?something that can be all-around (all-genre) ?
To anyone it may interest, I have uploaded a PCB layout for my compressor:
http://s81.photobucket.com/albums/j207/merlinblencowe/Compressor/
The layout is for the "light" version, which has only level and threshold controls (see associated schem) and electronic switching.
To bias the FET, set the footswitch to bypass mode. Input a suitable test signal and adjust bias until output signal is equal to input signal.
Wow thanks a lot! can i ask is this a quite compressor ? :D always asking this hehehe!
Thanks for the layout Merlin. I've been working on a perf layout for the 'full' version for several days now (harder than I thought), and I noticed you changed a couple of things for the light version. Most of it, obviously, is for the purpose of streamlining the controls, but the others I was wondering if you preferred in the 'light' configuration. Namely, the C2 100p cap on U1d, and the reversing of R17 and C7. The extra power filtering makes sense. I don't know much about electronics, but is it safe to assume that the added BC337s are part of a buffered bypass control?
I figure the answer to all of these questions is 'yes', but I'd rather ask than assume.
Thanks for sharing your circuit, and I appreciate the help. I'm looking forward to eventually getting this thing together. :)
ill give this a shot next @ but im a bit confused on the layout? no signs i dont know ctrl usage? is it the switch? for momentary? :D
Quote from: auden100 on February 21, 2011, 08:54:29 AM
Namely, the C2 100p cap on U1d,
That just limits the upper bandwidth of the amplifier stage; standard practice. Doesn't affect it audibly.
Quoteand the reversing of R17 and C7.
That was to make layout easier. Since they're in series, it doesn't matter which way round those components go.
QuoteI don't know much about electronics, but is it safe to assume that the added BC337s are part of a buffered bypass control?
Yep. Q2 disables the side chain and Q3 shorts the level pot, returning the gain to unity during bypass mode.
Got around to finishing this. Unverified, but I think it should work. May still try to clean things up a bit. This was one tricky circuit to layout. If anyone sees an error, let me know. I combined the revisions in the Light version with the controls in the Full version. There wasn't an object that looked like the trimmers that I use (from futurlec), so I substituted with the three vero cut symbols.
Roughly, 7cm by 4cm. Should fit comfortably in a 1590BB.
(http://img.photobucket.com/albums/v504/auden100/ValveWizard_Layout1.jpg)
I am a fan of my Pigtronix Philosopher's Tone. It adds what you need and lets you blend your dry signal with the effect nicely so you don't lose your original sound. Plus it has a rad analog dist which doesn't work for everyting but has its place for sure.
The MXR Sustain Unit looks pretty interesting too.
Quote from: auden100 on February 22, 2011, 10:53:05 AM
Got around to finishing this. Unverified, but I think it should work. May still try to clean things up a bit. This was one tricky circuit to layout. If anyone sees an error, let me know. I combined the revisions in the Light version with the controls in the Full version. There wasn't an object that looked like the trimmers that I use (from futurlec), so I substituted with the three vero cut symbols.
Roughly, 7cm by 4cm. Should fit comfortably in a 1590BB.
(http://img.photobucket.com/albums/v504/auden100/ValveWizard_Layout1.jpg)
now this is a clear layout@ :D
Thanks. Used the new DIYLC V3 Beta. Exported to PDF, and then converted to 300dpi jpeg. Getting very clear results that way.
Quote from: mr_deadmaxxx on February 21, 2011, 04:32:16 AM
i think i have decided to go with an Ibanez CP9..is this a good compressor?something that can be all-around (all-genre) ?
I've found in my experience with compressors is that there is never really one all-around one that will work great with everything and every style. The CP9 is a great design, as it blends the top end of your original signal with the compressed signal. It'll probably work very well for most styles and genres.
Auden100 can you make it in pcb :D ? i wanna try your layout soon :D
Sheesh... Merlin is not only the 'Valve Wizard',
he is an 'Effect Wizard' as well ! I'll bet he has
one of the seven 'Electronic Rings of Power'.
We're all lucky that he is a GOOD wizard.
So Merlin, when does your Effects Book get released?
Soon, I hope, as I've got $40 burning a hole in my pocket.
(It will be devalued to $30 by this summer... please hurry!)
I have had the "light" version of Merlin's compressor on my breadboard for about a week now. Over all it is a pretty nice compressor but I had to make some changes to get it to work with my gear and the components I have on hand. First off I didn't have any J112 Fets so I tried what I have which is J201, 2N5457 and 2N5458. I also had to change R9 (4K7) to 470 ohms and the threshhold pot from 50K to 5K in order to get a decent range of control. I tried several of each of the fets I have and found that the J201 made the threshold way too touchy. The 2N5457 was a little better and the 2N5458 was the best of the three. I couldn"t get much compression at all with the threshold at 50K and R9 at 4K7. Merlin (if you are out there) I assume these changes I had to make are all do to the VGSoff of the fet being incorrect?
Quote from: Ripdivot on March 26, 2011, 06:08:38 PM
Merlin (if you are out there) I assume these changes I had to make are all do to the VGSoff of the fet being incorrect?
Yes almost certainly. The J201 needs less than -1.5V to turn off- very sensitive!
However, I am surprised that you needed to
reduce the threshold resistor, because that would
increase the gain of side chain, yet that FET needs
less voltage to drive than my version! Did you use a scope to bias the FET, or ears?
EDIT: Ack! Just noticed that D1 and D2 are both backwards in my schematics! I am updating them now. This would explain your problem, sorry! :icon_redface:
Here's a vero layout (unverified). Doesn't include the electronic switching, it's for DIYers with old skool bypass.
BOM here: http://s81.photobucket.com/albums/j207/merlinblencowe/Compressor/
(http://i81.photobucket.com/albums/j207/merlinblencowe/Compressor/CompressorVero.jpg)
Merlin, so I changed the diodes around so they are placed correctly and reinstalled the original components and it works OK. I still had to drop the threshold resistor down to 1K to get a better compression range. This must still be because of the incorrect fet. As it stands now (with the 2N5458 Fet) my circuit works best with a 25K threshold pot and a 1K threshold resistor. I will try and source a J112 this week and report back with my findings. It works nice in the subtle settings but gets pretty hissy with more compression. Sometimes I wish I could get a lot more squash out of it...
QuoteIt works nice in the subtle settings but gets pretty hissy with more compression.Sometimes I wish I could get a lot more squash out of it...
That seems to suggest a problem. With the side chain gain at max, such that you need to tunr the level way up to hiss levels, you should be getting
mammoth amounts of squish!
Here are some initial characteristics I measured. x-axis is input signal in mV(p-p) and y-axis is output in mV(p-p) with level at minimum.
All curves are with with max ratio, except where noted.
With everything dimed the knee starts around 20mVp-p input, levelling off at about 20dB compression, which is serious squish!
(http://i81.photobucket.com/albums/j207/merlinblencowe/Compressor/Comp.jpg)
Here are the numbers I am getting (25K threshold pot and 1K threshold resistor, 2N5458 Fet):
with controls at minimum
-30db in / -31db out
-20db in / -23dbout
-10db in / -15db out
0db in / -6db out
with threshold maxed and gain at minimum
-30db in / -37db out
-20db in / -30db out
-10db in / -24db out
0db in / -14db out
Quote from: Ripdivot on March 28, 2011, 12:17:56 AM
Here are the numbers I am getting (25K threshold pot and 1K threshold resistor, 2N5458 Fet):
with threshold maxed and gain at minimum
-30db in / -37db out
-20db in / -30db out
-10db in / -24db out
0db in / -14db out
OK, those numbers don't look
too bad, since you're getting 14dB compression max. In which case, I'm surprised you want more squish...
Part of the issue is that I am playing a strat which doesn't have all that much output so at times it seems like there isn't much compression. Thanks for all your help Merlin! I will still report back when I try the J112 Fet.
Quote from: Ripdivot on March 28, 2011, 11:25:26 AM
Part of the issue is that I am playing a strat which doesn't have all that much output so at times it seems like there isn't much compression. Thanks for all your help Merlin! I will still report back when I try the J112 Fet.
I suggest you just fiddle with the FET bias, it's very sensitive. May get you what you;re looking for.
As for the noise, I had a brain wave yesterday. With one extra resistor you can get a major noise improvement. Down side is you sacrifice headroom, but with a strat you probably don't need 6V headroom anyway! Been playing with it today, I think with some tweaking I might be able to eliminate the level knob, potentially making a one-knob compressor! The extra resistor is the 10k feedback on U1a. As you can see, as you lower the threshold it simultaneously increases the pregain.
(http://i81.photobucket.com/albums/j207/merlinblencowe/Compressor/CompressorIISchem.jpg)
Very cool idea Merlin, I'll give this a try in the next few days. Too late to make noise at the moment...
Merlin, could I not increase the sensitivity of the compressor by increasing the 100K resistor in the feedback loop of U1b? This should cause it to start compressing sooner with week pickups or lower level inputs would it not?
Quote from: Ripdivot on March 29, 2011, 03:03:43 PM
Merlin, could I not increase the sensitivity of the compressor by increasing the 100K resistor in the feedback loop of U1b? This should cause it to start compressing sooner with week pickups or lower level inputs would it not?
Yes, you could try that. But I still think even your 'weak' pickups shouldn't be so weak that it wouldn't work as shown. Let me know how you get on.
Incidentally, I'm currently using a 4.7k feedback resistor on U1a, 1k+47k input to U1b and a 47k feedback resistor on U1b.
Hi,
I have a 1980 DynaComp "mint" block logo unit, an Ibanez CP-9 of the early 80's, and an "somewhat unknown" EXAR Compressor (stompboxes from Poland, probably from the early 90's). The CP-9 is not worth - forget it ! The DynaComp is nice but sounds nothing more than correct, and the best is the Polish EXAR : better transparency, better sustain, less noise... It has DBX IC inside, and the stompbox is crammed...
A+!
Brilliant method of adjusting the threshold/pregain, Merlin. I like that a lot.
From the look of the circuit, it seems you've biased the JFET so the difference between ON and OFF resistance is not very large (some J112s won't turn fully off). What's the reasoning behind using the J112 versus say a J113 or J201?
Quote from: earthtonesaudio on June 28, 2011, 09:52:26 PM
What's the reasoning behind using the J112 versus say a J113 or J201?
Simply because that's what I had, and most of them worked equally well. J113 and J201 should also work, probably better.
Hey folks, I'm gonna raise this page from the dead for a bit, hope that's chill. I've been working on the Valve Wizard Compressor, and trying to come up with a way to meter how much Gain Reduction is going on and settled on using an LM3915 LED Driver chip. The question on my mind though is how and where do I have the Chip monitor from? I could take it off from the input to the JFET, but that wouldn't include the rather important effect of the Ratio control. Otherwise I could take it off of the source of the JFET, but I'm concerned that in order to not interfere with the Ratio control I would need to have a very heavy resistance going to the LM3915; and I remember reading that it becomes less accurate/reliable with a particularly high input impedance. So what would people suggest? Thanks for any input folks!
If you want accuracy the "right" way would be 10log(output/input) which means an instrumentation amplifier, rectifier, and log converter all to drive the input of the LM3915.
But that's easily just as complex as the pedal itself. How about settle for a little less accuracy and simply use the CV? Ah but the ratio control...
Okay then, make the Ratio control a dual ganged pot and use the other half to mix in an offset to the CV you're feeding into the LM3915.
Merlin - your solution certainly looks easier than building the Carl Martin.
Do you see any real benefits (or trouble) making it work off a bipolar supply? 9v supply is easy, sure, but bipolar isn't much more trouble for me, so if there are benefits, I'll do it.
I guess if I just breadboarded it myself, I'd know....but always nice to ask the designer in these rare cases when that is possible. =)
Quote from: liquids on December 16, 2011, 08:32:41 AM
Merlin -
Do you see any real benefits (or trouble) making it work off a bipolar supply?
Yes you could use a bipolar supply, which would certainly give you more headroom.
I should say, though, that I have gone off this design. I don't like the way it sacrifices headroom for lower threshold. I am still playing with topologies to get low noise and low ratio, with simple parts...
Quote from: merlinb on December 17, 2011, 06:20:00 AM
Quote from: liquids on December 16, 2011, 08:32:41 AM
Merlin -
Do you see any real benefits (or trouble) making it work off a bipolar supply?
I don't like the way it sacrifices headroom for lower threshold. I am still playing with topologies to get low noise and low ratio, with simple parts...
Do you plan on sharing your new design when it's done?
I just discovered this thread (I'm kinda new here) and I like all the control on compression/sustain your last design permitted. I hope your new design will have that same flexibility.
thanks!
Quote from: Jorge_S on December 17, 2011, 11:44:35 PM
Do you plan on sharing your new design when it's done?
Of course!
I will be a while though, as I'm currently working on a signal generator, delay pedal and phono amp.
hi everyone,
Has anyone built this compressor : http://www.sugardas.lt/~igoramps/article60.html on this russian site and tried it on bass. One thing i believe it would be nice and responsive being fet. But i have tried different compressor and i have found in general i should say there always variations to the rule. But VCA compressor seem to be hissy. Fet compressor tend to be pumpy if not controlled properly as the fet triggers so quickly. I was quite pleasantly suprised with transistors used as attenuation. Cause there a bit slower than fets they tend to be warmer and not so trigger happy. The one i haven't played with which i intend to do some prototypes with is the TDA7052a this chip acts similar to a vca with the dc volume control option on it. basically you have to control the variation between 0.3 and about 1.4v but the it can happily ride above 1.4 and just dip down as far as needed to compress by using some type of pot to contol the threshold. Well this is as far i assume for now. Only time will tell once i do the prototype. Of what i can work out or hoping it should be the most hifi of all or the other word used for hifi is transparent. as being it is a dc volume control the distortion levels due to the chips charecteristics should keep distortion levels essentialy not audible. If anyone has any suggestions on what else could be done i'd love to hear from you. I would also love to know what that russian fet compressor is like especially on bass. Cheers ;D
I just ordered a 4301 chip last week and I am surprised at how much I like it. Of course it is an expensive chip to blow up, so it should be treated carefully on the breadboard, and is best when run off bipolar supply, but it's a chip more or less designed for a compressor, and it's the best I've tried outside or alongside the RNC. No hiss even when maxed out, from what I am hearing.
Familiarity with THAT's design notes helps a lot though. The best feature in a compressor (that is lacking from the stomboxers) is a threshold control. I use my guitar's volume control a lot. With the threshold set properly, the compressor will affect my signal with the guitar's volume maxed, but when I dial it back, the compressor's threshold is no longer met and I can retain the ability to 'cleanup' overdrive pedals that follow it.
the only thing the that 4301 has going for it versus other vca's is the rms or averaging of the signal other than that it really doesn't do much for me other than hurt my wallet theres lots of chips that easily sound as good.
Quote from: pedalgrinder on December 27, 2011, 06:22:57 AM
I would also love to know what that russian fet compressor is like especially on bass. Cheers ;D
You should breadboard it, then you'll know more for yourself.
i have and i think there average
> raise this page from the dead ... a way to meter how much Gain Reduction is going on ...an LM3915
(http://i.imgur.com/hQ4YA.gif)
Out of all the layouts posted on this thread (for the Merlin compressor), are any of them verified and ready to build? I want to start on a compressor project for this weekend, but I don't want to make a layout if there is one out there that is verified (reinventing the wheel and all that...)
Thanks!
Quote from: O on February 25, 2012, 02:24:18 AM
Out of all the layouts posted on this thread (for the Merlin compressor), are any of them verified and ready to build? I want to start on a compressor project for this weekend, but I don't want to make a layout if there is one out there that is verified (reinventing the wheel and all that...)
To be honest, I wouldn't bother to build that design now. I have a far superior compressor in the pipeline, which should be released in a few weeks. It uses an LM13700 and a couple of opamps, and has performance that will shatter all the other DIY compressors. Watch this space... :icon_twisted:
Quote from: merlinb on February 25, 2012, 11:12:08 AM
To be honest, I wouldn't bother to build that design now. I have a far superior compressor in the pipeline, which should be released in a few weeks. It uses an LM13700 and a couple of opamps, and has performance that will shatter all the other DIY compressors. Watch this space... :icon_twisted:
allrighty then... I'll keep my eyes on this thread. ;)
ooh oohhh me too...been thinking of building a comp.... :icon_cool: :icon_cool: :icon_cool:
A better compressor is coming...
- Four times more headroom than a Dynacomp?
- Half the noise of a Dynacomp?
- Same available sustain as a Dynacomp?
- Fewer parts and cheaper than a Dynacomp?
- Possibility for all five knobs?
- Fits in a 1590B?
- Millennium bypass?
If you answered 'yes' to all of the above, then you might be the Engineer's thumb.... Just to wet your appetite, he's a sneak preview:
(http://i81.photobucket.com/albums/j207/merlinblencowe/Engineers%20Thumb%20Compressor/engineersthumbvero.jpg)
we want soundclips :icon_eek: ;D ;D ;D
we want everything :icon_mrgreen: :icon_mrgreen: :icon_mrgreen:
I want that bad!!!!!!! :icon_mrgreen:
+1+1+1...^ :)
more more more more more!
Awwww yeah! ;D CANT WAIT FOR FINAL CIRCUIT! OMG! *dies* :icon_eek:
Ah I love compressors! this looks great cant wait to build it!
Me too.+++
I've got my LM13700s on order. When you're ready, post a schematic.
About the BC327; what would be good replacements for that? 2N2907? 2N4403?
this is soo off topic but ;
i updated VLC media player tonight and the new version includes an audio compressor !
i have been moaning about that for years . now i can watch movies and tv at all hours of the morning without having to constantly jerk the volume up and down with the mouse . yea VLC !!!!
it has an eq as well and its a bit off the path to save the all the settings but man is it nice .
Four times the headroom with a 9V supply? Alchemy!
I'll post the schem when I have finished decorating the enclosure and done sound clips. The actual circuit is finalised though. Very layout unconfirmed, but thoroughly checked so far!
Quote from: waltk on April 13, 2012, 10:00:49 PM
About the BC327; what would be good replacements for that? 2N2907? 2N4403?
Any PNP should work if you take care to check the pinout. 2N3906 and any of those you mentioned should be OK. Not sure how you choose your transistors in the US!
Quote
Four times the headroom with a 9V supply?
It may run on 9V but the Dyna has less than 1Vp-p headroom! Not too hard to improve on that...
QuoteI'll post the schem when I have finished decorating the enclosure and done sound clips.
Thanks Merlin. Can't wait to see it...
QuoteNot sure how you choose your transistors in the US!
We start by picking anything that doesn't start with BC :).
Seriously, the 2n3904 and 2n3906 are probably the cheapest and most widely available. I would use these first (for NPN and PNP respectively) unless there was a specific requirement for some other characteristic (like higher or lower hFE). I noticed the BC327 supports Collector current up to 800ma, but the 2N3906 has an absolute maximum Collector current of 200ma - that's why I asked.
Quote from: merlinb on April 13, 2012, 05:56:50 AM
Just to wet your appetite, he's a sneak preview:
(http://i81.photobucket.com/albums/j207/merlinblencowe/Engineers%20Thumb%20Compressor/engineersthumbvero.jpg)
:icon_eek: :icon_razz: Feedforward? Or are these old eyes missing something? (apart from an R10!)
Anyway, looking forward to seeing it taking shape merlinb!
Quote from: gritz on April 15, 2012, 02:44:06 AM
:icon_eek: :icon_razz: Feedforward?
Very well spotted!
i just finished my first compressor (optical) when this thread caught my attention.
looking forward to schematic and a bit of explaining of whats really going in there for us newbies.
believe a new thread is in order for this circut.
Hi,
there's definitely a need for a schematic: In case I wanna use a electrolytic cap for c4 and c5 which orientation should they have? Without a schem its nearly impossible to say that without too much effort! ;)
Thx!
Helge
Quote from: Fuzz Aldryn on April 16, 2012, 11:05:36 AM
In case I wanna use a electrolytic cap for c4 and c5 which orientation should they have? Without a schem its nearly impossible to say that without too much effort! ;)
It's not impossible- in fact its very easy! You can see that those capacitors connect to ground (just follow the back lines...) so that end of the caps must be negative.
Here is a quick sound clip. The first half is clean signal that I recorded in. The second half is the same track played back through the compressor.
http://dl.dropbox.com/u/57831278/engineersthumb.mp3
A lot of the hiss you hear is from the original recording, being amplified by the compressor, rather than coming from the compressor itself. Some of the transients did also clip my sound card, but it's not too bad.
Here's a picture of the original and compressed tracks:
(http://i81.photobucket.com/albums/j207/merlinblencowe/Engineers%20Thumb%20Compressor/compressortrack.jpg)
Merlin - obviously this is a good compressor!
However, it's also nice to hear DIYers who have a bit of chops to play some music with the guitar and effects/circuit chops, too. :) Nicely done.
:icon_eek: :icon_eek: :icon_eek: ;D
Wow, very nice sound. Now I want to build it!
I've realized that I have all the part rigth here except the 13700. Will it work with 13600?
congratulation
Quote from: Le québécois on April 17, 2012, 12:35:26 PM
Will it work with 13600
I haven't tried, but AFAIK it should work- they're the same OTA inside, only the darlington pair is different, but that's not used in my circuit. You could always build it with 13600 and then buy a 13700 later on.
New thread started!
http://www.diystompboxes.com/smfforum/index.php?topic=97123.0
I designed this with a friend of mine round 1990:
(http://localhostr.com/file/CRVHW3I/pwm_comp.gif)
ps. there's an error in the drawing, U9A + and - pins are swapped
Precision FWR from input, controlling a variable resistor in the feedback loop of an opamp (got the idea from an eti magazine project).
But, unlike the ETI project, we didn't use an OTA.
Q2 and comparator U3A are a sawtooth oscillator (around 400kHz IIRC). This sawtooth is compared to the FWR output and so we have a PWM signal proportional to the input envelope. We use this to control some cmos switches that vary the amount of signal that is fed back around the opamp.
With a good, clean power supply, there's no strange noises. I think with a good layout (we only tested on protoboard) it can be less pricky about the power supply.
If you have a large transient, during the attack time the output of a limiter is larger than the set threshold, so even in the feedback loop an OTA input can be overdriven during a short time. Also if the ratio is not infinite you can overdrive the OTA. We designed this switched limiter to try to eliminate this distortion.
The circuit can be simplified, for example the FWR is overkill - it is way too fast.
Two other interesting compressors are mictester's "Really Cheap Compressor" and "Compression Sustainer", both posted at the other forum.
This one looks very interesting as well: http://www.hexeguitar.com/diy-tadek_e
I think Fuzz Aldryn has built it, maybe he can report.
Quote from: roseblood11 on May 01, 2012, 03:41:54 PM
Two other interesting compressors are mictester's "Really Cheap Compressor" and "Compression Sustainer", both posted at the other forum.
This one looks very interesting as well: http://www.hexeguitar.com/diy-tadek_e
I think Fuzz Aldryn has built it, maybe he can report.
Yeah, I do like the look of that design. In fact I like most of what I've seen from Hexe, schematics and pedals alike.
I mean, that chip is more or less a 8-pin single VCA that can function as a power amp, or a 1W power amp that can be used as a VCA or simple voltage controlled volume....pretty useful, though maybe I'm easily amused :)
Would love to compare noise under high squash settings. Right now I'm using a THAT 2159/2180 type in a circuit, but I kinda wish I ordered one of those chips with my last order....gotta put it on the parts list for next time.
Quote from: liquids on May 02, 2012, 09:13:20 AM
Would love to compare noise under high squash settings. Right now I'm using a THAT 2159/2180 type in a circuit, but I kinda wish I ordered one of those chips with my last order....gotta put it on the parts list for next time.
The TDA7052A is a noisy device, just check the data sheet! At max gain it reaches an alarming 650uV output noise... no better than an OTA, ala dynacomp.
Thanks for the heads up! Obviously, I had not read the datasheet too thoroughly... :icon_eek:
Quote from: roseblood11 on May 01, 2012, 03:41:54 PM
Two other interesting compressors are mictester's "Really Cheap Compressor" and "Compression Sustainer", both posted at the other forum.
This one looks very interesting as well: http://www.hexeguitar.com/diy-tadek_e
I think Fuzz Aldryn has built it, maybe he can report.
I'm new here so I'll ask, what is the "other forum"
the other forum is freeestompboxes oops take out one e you can judge the politics for yourself. On the other forum there is the Rothwell Love Squeeze sensational unit. Sabrotone has a vero of it on his site if you want to have a look. One of the best and easiest compressors to get going you only have to read the reviews on it that say it all. Thats what i reckon anyhow.
I've had / built quite a few compressors and have been a faithful CS3 user for 20 years..............and then I built the Diamond compressor as per Sabro's layout.
Compared to a "standard" Dynacomp:
- It's way less noisier
- It has WAY more output
- The compression range is (imho) far more usable, with less artifacts. It can be really subtle or squishy as hell
- It is WAY cleaner . very low background noise
- The switchable eq knob goes from pretty warm to quite bright
I guess i can say that (to me) is waaaay ahead of any other compressor I have tried (dynacomp, keeley, squeezer and the Rothwell, which I found rather disappointing and lacking any character). I think it does both the "so-transparent-you-don't-know-it's-on" thing as good as the chicken' pickin'............I highly recommend trying it
FWIW, here's a song I made using a clon of a Demeter Compulator, which is also an optocoupler based compressor, but it's way too subtle for me (and the Diamond does it with the comp knob at 1/3 of its range !!!)
yeah i agree the diamond compressor is a nice one. What has been annoying me is the guitar one is there but the bass diamond compressor no one knows what has changed in it. I want the bass one not the guitar one. If i start looking at that one i will start modding it to try and get it to work better with bass wishing i had the exact recipe of the bass diamond compressor. I think thats what has put me off building one.