Most variable compressor?

[Radamus]

Hello. I would like to build a compressor soon. I play bass, and I play with both slap and regular techniques, so compression could really tighten things up. I've looked into the orange squeezer because it is the most common and most loved, but it is subtle. I've also seen the OS +++ which is recommended for Bass, but I couldn't find any verification of whether it worked or not.

I've also read a bit about the ross compressor which is supposed to be more dramatic, but it still has limited controls. I've read the article here as well: http://psbg.emusician.com/ar/emusic_big_squeeze/index.htm

Is there a more variable compressor (subtle to drastic) available for DIY? Maybe something with decay control or maybe even a reverse setting for expansion?

Thanks
Conrad

[TELEFUNKON]

all here: http://www.thatcorp.com/appnotes.html

[Processaurus]

the dod 280 might be worth looking at for bass, being an optical compressor.  Same basic idea as the LA2A, a classic compressor for bass in the studio.

But for the most variable, Thatcorp's app notes might be a better place to start than typical stompbox compressors. 

If you're thinking of buying something,  the Really Nice Compressor is a well liked compressor for about $150, I'm liking it better than pedal compressors.

[rnfr]

the FMR RNC is the best value for the money you can buy.  it's a fantastic comp.

[Radamus]

Thanks guys!

I should have been more specific. I am looking for a stompbox type thing. I feel like the orange squeezer and ross might not have enough to offer me in just being able to play with knobs and invent sounds, but I'm not looking for a rack unit's worth of complexity. I'll check out the dod 280, though for sure, and I'll read that article. It looks like it might be a week's worth of reading, though, as I've got midterms this week. I should have guessed that there'd be a web page out there that explained everything.

Again, many thanks. I'll check back if I have more questions, but feel free to drop more opinions.

Edit: I looked up the dod 280 schematic and it appears to be even simpler than the orange squeezer, with one more knob. Is there a list of mods available? The search function turned up mostly nothing. I might have to compare the envelope with the meatball project to see how many parts I can borrow. Is it difficult to switch from compression to expansion? I know the meatball can switch from up to down sweep, so it makes sense.

[brett]

Hi

I should have been more specific. I am looking for a stompbox type thing. I feel like the orange squeezer and ross might not have enough to offer me in just being able to play with knobs and invent sounds

OS is subtle.  The Dyna/Ross is way huger.  There are quite a few mods you can do with the Ross.  Attack and delay controls as well as tonal stuff.  Note that the Ross is the Dyna, but it eats highs due to some filtering caps at the input.  For regular guitar, I like the Dyna much more as it doesn't mess with the tone.

The Boss CS-2 and later models are ok, but I like the Dyna better than the Boss pedals.  I think Small Bear still stocks the CA3080.  In some areas it is difficult to get.
cheers

[Radamus]

The dynacomp is always an option.  I think I can find those chips somewhere, and if they're anything like the 13700, I can probably just change the pins as necessary. I'm not sure there's much point in me following that layout because I perfboard and I've spent too much time ripping my hair out trying to make leads emulate a PCB. Can anyone verify that I can switch the OTA being used?

I've made several functional home LED/LDR's, so I'm kind of drawn to the dod 280. Does anyone know where I can find the envelope mods to add attack and decay, etc.?

Thanks

[Hanglow]

You could look at the flatline compressor as well for an optical one, it only has sustain and volume but there might be mods kicking about for it. It's nice, goes from slight compression to very squashed and you can get a nice boost out of it as well.

[Mark Hammer]

The sorts of controls one sees on rackmount studio compressors are generally there so as to permit the unit to adapt to the demands of a wide variety of input signal types.  What you need for drums is different than what is needed for bass or voice.

For my money, I think if you simply add a variable recovery time to whatever compressor you use, that will more than adequately address your needs for a single use (i.e., guitar or bass) compressor.

[Radamus]

I checked out the flatline. It's very similar to the dod 280 (in function more than part values). I think the dod 280 makes a little more sense to me, and it's probably simple enough that I can tweak it a little on my own.

For my money, I think if you simply add a variable recovery time to whatever compressor you use, that will more than adequately address your needs for a single use (i.e., guitar or bass) compressor.

That means attack control, right? The speed at which it starts to compress?

And can I do a DPDT switch to change the direction of the envelope? Is there much use for an expander? It sounds interesting to me, but I haven't tried it yet, so I'll let you guys tell me.

Thanks for all the suggestions. I hadn't read about the flatline or dod unit in any other thread, even when my search was simply "compressor."

[Mark Hammer]

For my money, I think if you simply add a variable recovery time to whatever compressor you use, that will more than adequately address your needs for a single use (i.e., guitar or bass) compressor.

That means attack control, right? The speed at which it starts to compress?

Not exactly. 

Imagine you're in a lineup at a club.  One person gets let in by the bouncer, and after the person goes inside, someone says to the bouncer "Hey, you know that person is under-age, right?"  The bouncer now goes "Oh crap!", and commences to check everyone else's ID, which slows down entry for everybody else, even though the first person got in easily and quickly.

The compressor reduces gain in response to the initial peak sensed.  As long as the voltage detected and held onto by the envelope follower is high enough, the gain will remain low.  If the envelope follower/rectifier holds onto that voltage for a while, then the gain will still be lower for a while.  If you wait long enough after the initial peak, then the gain will be restored and the attack of the next note will be heard.  If the next couple of notes follow the first one too quickly, though, then they suffer gain reduction brought on by the first note attack.  This means that because the gain reduction doesn't "recover" fast enough, you won't get to hear the initial "attack" of those subsequent notes.

The recovery mod adjusts how long the rectifier circuit holds onto the initially detected peak before letting it drain off.  By making the recovery-time shorter, it's a bit like giving the bouncer amnesia: they continue to let everyone else through with very little hassle because they have forgotten abot the previous person.  One of the reasons why many people like the Orange Squeezer is because the recovery time is very quick.  This means that any level reduction applied is only applied very very briefly.  The max volume of notes appears to be limited, but a certain amount of dynamics is still retained.  What a great many manufacturers have done with the basic Dynacomp circuit is to let the user reduce the recovery time so that gain recovery is fast enough to allow a bunch of quickly-following notes to be heard no differently than the first one.  If you are the sort of player who lingers on individual notes, you won't notice the difference.  But if you are a tele twanger who whips off flurries of notes by the bridge, then you'll appreciate shorter recovery time.

[Gus]

A 1176 can sound good on bass.

Google compressors like la2 1176 la4 etc.  Try out studio ones if possible and any effect ones you can.  When you find the one you like then you can DIY a design.

Things to read about side chain and the different types.  The read about the gain reduction method opto( led or bulb or electroluminescent ) photocell type, photofet ......., Fet VCR.  Then the That link posted above.

First you need to find out what kind you like, then you might have to design one for 9VDC.

There is a lot of information on the web about compressors.  What might at first sound like a simple question can grow.

Then there is feedback vs. feedforward.

[moosapotamus]

Also search here for "LA Light".

~ Charlie

[Radamus]

I checked for LA light and found this link: http://www.aronnelson.com/gallery/main.php/v/johan_0/LA_Light_last_one_001.gif.html
It makes sense to me, but I don't know much about circuit design.

In a couple of the forums I read, it said that there were several modifications made for bass guitar, including a link to your website, moosapotamus. The link didn't work because it went to moosapotamus.com, not .net, which is the one you have now(?), so I couldn't find your work on the project.

Also, how do the LED/LDR units work in this one? Do they all face one another or do they match up.

Thanks.

[Johan]

this is probably the one you want to build..


all the resistors and pots around the input, is straight out of the LA2a schematic, to get the same loading and responce as the real unit( or at least close to it)
the LDR creates a volumepot in conjuction with the input series resistors. the sidechain amp just drives the two LEDs, but filters out the lower frequencys to mimic the frequency responce of the electrolumence panel that sits in a LA2a. the resistor marked with a * is selected depending on your LEDs. when playing, you want to be able to adjust them from off to bright by turning the the pot. 470-1000 ohm is a god staring point
..it is quite subtle and probably not for those who want compresion for effect and want it to be really squeezy and obvious, but rather for those who want a compressor to do what it does without being too noticeble( wich is probably why not many guitarists go for this one,  but it sound great on bass and vocals..)....good luck

j

[Radamus]

Okay. It sounds pretty good, and thank you for posting that version of it. You described this design as subtle. I think that light compression is probably a good idea. Personally, I have never used a compressor, so I would like the option to mess with some more drastic controls as well. Does this design also achieve that? Just how subtle is subtle? As I said, I like to slap as well as play normally with my fingers. How would subtle compression change the sound of slapping? I'm kind of curious how the different tonal qualities of different volumes of playing sound when they're all at around the same level.

Thanks again.

[Toney]

I'd go with the LA light based on what you ask

It will suit your needs...

[Radamus]

Cool. And does anyone happen to know what flea uses? I've read a number of places that he uses a compressor sometimes, and that might be the key to getting some of his tones. I'm looking specifically on Blood Sugar Sex Magik.

Thanks

[lowstar]

if you´re after the bssm tone, go get yourself a wal bass before you think about the comp. 
and in the studio, they won´t have used a stompbox comp...prolly one of the usual suspects, a 1176, a la-2a, or something even more expensive. 

speaking about stompbox comps, even the compulator didn´t really make me happy. i found the carl martin to be pretty good, though.
but, on a side note: i don´t think that the bass player should compress his live sound. keep your dynamics intact and use them to your advantage !
and for recording, with digital recording techniques nowadays that have such a huge headroom (24bit), i´d record uncompressed and then use a good compressor-plug-in in the mix. unless you have really nice outboard gear available (i recorded a bass track a few months ago where the engineer used one of the new UA audio channelstrips, and boy, that really did sound good).

cheers,
lowstar

[Radamus]

if you´re after the bssm tone, go get yourself a wal bass before you think about the comp. 

I thought he was using a music man stingray? And getting the bssm sound isn't my only goal, it just seemed like an appropriate time to ask. Thanks for the input. I imagine that I will not use the compressor constantly, but I like the idea of having the different tonal qualities of a loud pluck have the same volume as a lighter pluck. Loud notes tend to have extra treble from smacking into something, and the louder notes never have the same tone otherwise, so it might be interesting to take the volume difference down a bit .

Has anyone been happy with the orange squeezer before? I originally put it on my list because it was one of those pedals that everyone builds, but then I got to wondering about how effective it would be for me.

Otherwise, I think I've gotten enough votes for LA light to put that one together. I might have to play around a bit with other envelope unites to see what kind of sound I can get. I'm not sure what an expander would sound like, but I might be able to figure that one out. Anyone have an opinion on the idea?