Aron is now stocking 5840 submini pentodes in the store: http://diystompboxes.com/zencart/index.php?main_page=index&cPath=19 So it's time for a few new 5840 projects. I've been working on this one on and off for the past month or so. It's evolved into something with quite a few interesting tonal possibilities.
First off, you'll notice that it has switchable diode clipping, this idea was suggested to me by Derringer in my "Muff Minor" thread (http://www.diystompboxes.com/smfforum/index.php?topic=75715.0), so I tried it and it worked well, adding a bit of sizzle to the clean boost and overdrive. There is a slight volume loss when the 'Dirt' switch is engaged, though there's enough boost in the circuit to compensate for this.
This design originally started out as a low voltage circuit, as it developed I thought it would be nice to get the voltages a little higher, so I added a little charge pump circuit based around a MAX1044 to get up to around 35 volts. Thanks to R.G. for his +18, +25, or +33 from one 9V battery (http://www.geofex.com/circuits/+9_to_33.htm) on which the charge pump circuit is based.
The tonestack is based on the BM tonestack, with just a few value changes to suit the circuit.
What does it do? Well it does clean boost with the Gain set at minimum, flick on the Dirt switch and you get some nice diode clipping too. Turn up the Gain and you'e into overdrive territory with diode clipping, flick the Dirt switch off and you get even more overdrive. All with some nice tonal variations courtesy of the tonestack. So many types of dirty, hence the name "Promiscuous Girlfriend".
I'll be adding soundclips later today with any luck.
I'm just putting the finishing touches to perf and PCB layouts, John Lyons has kindly consented to make up some PCBs for anyone whose interested. My good forum buddy Toney is putting together a vero layout too, so all bases are covered.
So, tubes available for Aron's store, layouts in three different formats, PCB availability - what are you waiting for?
(http://i210.photobucket.com/albums/bb292/frequencycentral/PromiscuousGirlfriendFinal.jpg)
Perf layout, unverified, I'll build it soon.
(http://i210.photobucket.com/albums/bb292/frequencycentral/PromiscuousGirlfriendPerf.gif)
PCB layout and PnP, unverified, but pretty much identical to the perf layout, so when the perf is verified so will be the PCB.
(http://i210.photobucket.com/albums/bb292/frequencycentral/PromiscuousGirlfriendPCB.gif)
(http://i210.photobucket.com/albums/bb292/frequencycentral/PromiscuousGirlfriendPnP.gif)
Looks cool Rick, I'll have to get some of those tubes before Aron sells out. Love the name.
So happy to see this finally realized!
A lot has gone into making this happen from all corners of the globe!
I'll be offering a Vero sometime really soon. I have a killer week coming up so hopefully by the weekend. It's already Late Sunday night in Melbourne.
Cheers, this should be a real winner. :D
Here's some soundclips, they don't explore every possibility but give a bit of a flavour.
Signal path:
Squier Telecaster Custom (bridge humbucker) >>> Promiscuous Girlfriend >>> Roland Bolt 60 watt tube combo >>> Shure SM58 >>> Event Echo Gina 24 soundcard >>> Wavelab
No other processing.
The first clip has the effect bypassed, then with minimum Gain and the Dirt switched off: http://files.getdropbox.com/u/967492/Bypass%20and%20Boost.mp3
Minimum Gain, Dirt switched on: http://files.getdropbox.com/u/967492/low%20Gain%20plus%20Dirt.mp3
Maximum Gain, Dirt switched on, Tone set low: http://files.getdropbox.com/u/967492/high%20Gain%20plus%20Dirt%20low%20Tone.mp3
Maximum Gain, Dirt switched on, Tone set high: http://files.getdropbox.com/u/967492/high%20Gain%20plus%20Dirt%20high%20Tone.mp3
Maximum Gain, Dirt switched off, Tone set low: http://files.getdropbox.com/u/967492/high%20Gain%20no%20Dirt%20low%20Tone.mp3
Maximum Gain, Dirt switched off, Tone set high: http://files.getdropbox.com/u/967492/high%20Gain%20plus%20Dirt%20high%20Tone.mp3
I like it, very interesting tone! Ballsy overdrive with a touch of fuzz! Added to my to do list. :icon_redface:
(http://i210.photobucket.com/albums/bb292/frequencycentral/000_0001-14.jpg)
(http://i210.photobucket.com/albums/bb292/frequencycentral/000_0002-9.jpg)
damn you do nice work FC !
those tubes look like missiles ... they aren't perchance the ones that were actually used for missile guiadance are they?
Quote from: Derringer on July 07, 2009, 03:36:39 PM
damn you do nice work FC !
those tubes look like missiles ... they aren't perchance the ones that were actually used for missile guiadance are they?
Thanks Bill!
The romantic in me says intercontinental ballistic missile guidance systems. :icon_mrgreen:
The realist in me say geriactric hearing aids. :-\
hahahha
well ... in either case ... they are being put to a better use now!
There's a missed trace on the PCB layout, and I've subtley changed a couple of component positions having now built it, so I'll delete and re-upload the layouts when I've amended them.
EDIT: Now fixed!!
Quote from: frequencycentral on July 07, 2009, 03:23:36 PM
(http://i210.photobucket.com/albums/bb292/frequencycentral/000_0001-14.jpg)
(http://i210.photobucket.com/albums/bb292/frequencycentral/000_0002-9.jpg)
Your perf boarding is otherworldly... I cannot even fathom making such a perfect perfboard. It's just too much for me to handle. You really need to make that tutorial video I mentioned in the other thread! :P
The sound sample sound great Rick. niice work as usual.
Those long runs on your perfboard of the amplifier... Are they wire with no insulation on them or what are they? I must know your secrets. :P Do you make some sort of rail that follows where all the traces are of stripped wire and then solder components to that hovering rail?
Quote from: doitle on July 11, 2009, 02:29:58 AM
Those long runs on your perfboard of the amplifier... Are they wire with no insulation on them or what are they? I must know your secrets. :P Do you make some sort of rail that follows where all the traces are of stripped wire and then solder components to that hovering rail?
Some of the long runs are bent component legs (mostly resistor), pop the component into the board, bend the legs over flat to the board so they're pointing in the direction they need to go, then solder. Where there are short gaps to fill I use cut off resistor legs as bridges. Where there are long runs I use wire with the insulation stripped. I generally place and solder the components then do the long runs as oppossed to the 'hovering rail', but I do sometimes use a 'hovering rail' too - I did that on my Phase 180 build for the really long runs. The disadvantage of bending component legs to make the bridges is that it's difficult to remove the component if you make an error, so be sure it's correct to start with, and work from a layout you're really sure of.
Just drilled the enclosure, everything appears to be in the correct position. Now to sand it and apply the graphic.
(http://i210.photobucket.com/albums/bb292/frequencycentral/000_0004-6.jpg)
Greetings. Am VERY interested in this as well as the boost but want to buy a all ready made PCB. Where are they?
Thanks bro. Please contact me at everettsorb@aol.com regarding this.
Quote from: everettsorb on July 12, 2009, 11:12:05 AM
Greetings. Am VERY interested in this as well as the boost but want to buy a all ready made PCB. Where are they?
Thanks bro. Please contact me at everettsorb@aol.com regarding this.
Hi, I'm sure John Lyons (http://www.diystompboxes.com/smfforum/index.php?action=profile;u=1334) would be more than happy to provide a PCB for you. But give it a week, as I'm in the middle of my build and need to confirm that my layout is bug-free before John makes up any PCBs.
I've already had to move C2, C9 and C14 to different locations on my perfboard to make room for the output socket - this would only matter if you plan to box it up the same way I have. I'll update the layouts anyway sometime this week.
Graphic now applied to the enclosure:
(http://i210.photobucket.com/albums/bb292/frequencycentral/000_0005-6.jpg)
I love it when a plan comes together.........................now I need to wait for it to dry..............
My mum will be so chuffed that you've used her picture!
Quote from: markeebee on July 12, 2009, 02:34:47 PM
My mum will be so chuffed that you've used her picture!
That's not you mum Mark (or is it???), that's Grog, vocals/bass in the UK band Die So Fluid (http://www.diesofluid.net/), she looks like she'd rip off my testicles with her teeth if she found out I used her image on a pedal with such a name! :icon_twisted:
Nice graphic...Still I have to say this project didn't get me interested as the previous ones...Gotta work on some mini-amp soon...
Quote from: Renegadrian on July 13, 2009, 05:01:17 AM
Nice graphic...Still I have to say this project didn't get me interested as the previous ones...Gotta work on some mini-amp soon...
I kinda know what you mean, as there are so many tube projects to choose from now. If it was 'just another tube overdrive' I couldn't have brought myself to build it. Fact is, the tonal palette is much broader than say the Valvy or Pepper Shredder - but I know you won't like the diodes Adriano, but give them a chance!
Rick, your project is quite good, and let's say it covers a submini tube territory, a "promiscous" overdrive, and that's quite good, so your effort is appreciated. :icon_wink:.
I am towards other tube "territories" ATM, not necessarily submini and with some extra gain in mind.
Said that it's good to have different projects (tremoloes, overdrive, boosters, heavy distortion, amps and so on) to choose from...
Quote from: Renegadrian on July 13, 2009, 12:18:20 PM
Rick, your project is quite good, and let's say it covers a submini tube territory, a "promiscous" overdrive, and that's quite good, so your effort is appreciated. :icon_wink:.
I am towards other tube "territories" ATM, not necessarily submini and with some extra gain in mind.
Said that it's good to have different projects (tremoloes, overdrive, boosters, heavy distortion, amps and so on) to choose from...
Higher gain will hopefully be one of my project goals in the amp I've been working up a design for and acquiring parts on. So far I've got a 6112 which is quite a bit higher gain than the 6111. (20 vs 70) I've been trawling around ebay because I really had hoped to run two 6112s cascaded and possibly have a clean/lead or rhythm/lead switch capability for bypassing one of them. I've still got a long way to go before I understand enough to have that all going though :P Yet the tubes are almost here! If only I didn't have work and school and could just sit around all day learning tube amplifier design...
Well, doitle, I just finished a somewhat similar project (I will update the thread when I get home tonight), but let me tell you, you can get a very good amount of distortion with 6021's. I found the 6112's to be lower in output level, but I still have yet to do a project built around them to play to their strong suits. If you want to hear what a 6021 and 6111 can do, look for my thread later tonight about the Kitchen Sink submini amplifier.
Rick, I must say that I wasn't too won over by this myself, but I also find straight up pentode clipping to not be as musical as triode clipping. Don't know why, but I think the 6418 is the only pentode I've ever really heard that I thought "Now that sounds good, regardless of what type of tube it is". But hey, you are pushing the field further and I respect you for that. I'm still looking forward to a submini wah (I have actually thought of doing the colorsound inductorless wah with a 6111, wouldn't that be fun?). Actually, now that I think of it, I have a boatload of 6418's, maybe I should wire one up in triode mode and put it in a wah...I'll have to breadboard that tonight. Again, nothing but respect, but just not my flavor (momma always told me to stay away from promiscuous girls...).
I certainly look forward to your thread update Ripthorn.
Also, you found the 6112s to be lower output? Shouldn't they naturally be higher output since they have a higher mu? Just as far as my understanding goes in an identical circuit and with enough headroom shouldn't that mean that you would have a higher gain with the 6112 than the 6111 which in turn would mean your output signal would be larger?
Both Rick and I found that if we put the 6112 into a circuit designed around the 6111 (or 6021) that the output level was lower, though you could get more clipping. Strange, I know, but that is what happened at least in my case and Rick said he found the same. Best way to decide is go on and do it. You could well use the 6112 for two stages and a 6021 or 6111 for the other two stages and see what works best (6112 before 6111 or vice versa). I'm gonna try to breadboard the submini inductorless wah tonight and start a thread about that because that idea hasn't left my head since I typed it up.
Nothing could have prepared me for how tiny these tubes are! I just got a box of 6205 Pentodes I bought off Ebay. The seller was nice enough to include an extra one. Now if my 6112 would arrive I could get to bread boarding! I suppose I better solve my transformer quandry rather quickly too or I wont be able to actually proceed on testing out amp designs...
While you wait why don't you breadboard Adriano's 6205 design: http://www.diystompboxes.com/smfforum/index.php?topic=76372.0
Quote from: doitle on July 15, 2009, 02:37:37 PM
I suppose I better solve my transformer quandry rather quickly too or I wont be able to actually proceed on testing out amp designs...
If you're not sure which transformer you need and want to try a few different designs you could get a Hammond 125ASE for single ended or 125A for P/P. They have a gazillions different secondary winding options.
Oh neato I will certainly try out that lone wolf. I'll have to do some thinking as to how to get the 6.3V for the filament... If it is rated for 6.3V AC for the filament then a 9V DC supply would be almost dead on. 6.3VAC rectified would be roughly 6.3V*1.414 or 8.9V. I wonder if it would work at all with such a low B+... My LT1054 samples are still in shipment and so I dont have any way to boost the voltage really as of yet. I do have this transformer I pulled out of a clock radio that I THINK has a 36V and 24V secondary but I'm not sure and still need to learn more about working with transformers. I just measured the resistances accross the primary and the 2 secondaries and that's the ratio I came up with.
Also I've got a CB radio partially taken apart with two transformers in it that I have to desolder at so me point today. I really wish I knew how to tell some things about a transformer by measuring it or looking at it rather than having to just hook it up and hope it doesn't explode and take some voltages.
Quote from: doitle on July 15, 2009, 03:32:11 PM
I'll have to do some thinking as to how to get the 6.3V for the filament... If it is rated for 6.3V AC for the filament then a 9V DC supply would be almost dead on. 6.3VAC rectified would be roughly 6.3V*1.414 or 8.9V.
It wants 6.3 volts, AC or DC.
9 volts DC will decrease the life of the tube and will burn out the heater if run for any length of time.
There's a few ways to get 6.3 volts - 7806 voltage regulator, a little LM317 based circuit, or a voltage drop resistor.
You can also use a 6.2V zener diode.
(http://i210.photobucket.com/albums/bb292/frequencycentral/000_0004-7.jpg)
(http://i210.photobucket.com/albums/bb292/frequencycentral/000_0003-8.jpg)
(http://i210.photobucket.com/albums/bb292/frequencycentral/000_0005-7.jpg)
(http://i210.photobucket.com/albums/bb292/frequencycentral/000_0001-15.jpg)
How could it operate the same from 6.3V AC or DC. 6.3VDC would be equivalent to 4.5V RMS AC. Maybe there is a better datasheet floating around somewhere for this tube. The one I have is sparse in information about the heater.
Anyhow I'll probably just do a little KVL and drop extra voltage across a resistor.
Any ideas though about it's operation on low B+ like the valvecaster? I'm writing two papers for an art summer school class so I can't try it out yet but I will get to experimenting as soon as I can!
You know Rick, after looking at that box, you should have called the dirt control "cheat" or something (though is it cheating if you know she's promiscuous?). Looks great though, another amazing project with mad perf skills.
This thing sounds a lot like a little tube amp I built out of an old aircraft radio. Almost a nasally compression thing going on when cranked up. It's not a sound you find in a lot of other pedals. Nice work, per usual, Rick.
I just came across these on Ebay and was thinking of buying one as an output transformer. Sounds pretty versatile and I don't think I'd ever try to build something greater than 10W.
http://cgi.ebay.com/Tube-amp-10-15-watt-output-transformer-6L6-6V6-6BQ5-etc_W0QQitemZ390069236209QQcmdZViewItemQQptZVintage_Electronics_R2?hash=item5ad1f031f1&_trksid=p3911.c0.m14&_trkparms=65:12|66:1|39:1|72:1205|293:2|294:25
Seems like a good deal and I'd definitely buy one if I just knew whether they would work for these kinds of projects or not for sure. I know the seller is good because I just received a 6112 from him today. I really need to finish these papers and get to experimentin'! :P
I have one of those transformers..but haven't used it yet. I believe it has taps to match the reverb transformer used in the murder one amp.
Hopefully I can test it tonight and let you know.
-Berger
For anyone who does plan to build this pedal, be aware that the 3PDT wiring really does need to be the input-grounded-when-bypassed type. I've had to change my 3PDT wiring from how it is in the photos to combat high frequency oscillation when the effect is bypassed with the gain is above 1 o'clock.
fyi I tried the one I bought last night with my murder one and it worked fine. So i'll probably have to get some more at some point in time.
-Berger
Quote from: doitle on July 16, 2009, 03:00:28 PM
I just came across these on Ebay and was thinking of buying one as an output transformer. Sounds pretty versatile and I don't think I'd ever try to build something greater than 10W.
http://cgi.ebay.com/Tube-amp-10-15-watt-output-transformer-6L6-6V6-6BQ5-etc_W0QQitemZ390069236209QQcmdZViewItemQQptZVintage_Electronics_R2?hash=item5ad1f031f1&_trksid=p3911.c0.m14&_trkparms=65:12|66:1|39:1|72:1205|293:2|294:25
Seems like a good deal and I'd definitely buy one if I just knew whether they would work for these kinds of projects or not for sure. I know the seller is good because I just received a 6112 from him today. I really need to finish these papers and get to experimentin'! :P
For those that Vero....
http://www.aronnelson.com/gallery/main.php/v/Toneys-Album/Prom+Girl.gif.html?g2_imageViewsIndex=1 (http://www.aronnelson.com/gallery/main.php/v/Toneys-Album/Prom+Girl.gif.html?g2_imageViewsIndex=1)
NOTE: This was done late at night last weekend, so please check it against the schem in this thread and report any errors or improvements.
:D
I ordered two 70 Volt Line Transformers off Ebay. Maybe I can figure out how to use one as an output for this or a similar submini amp. I'm so excited to get home and open my package and get experimentin'!
Quote from: doitle on August 08, 2009, 02:33:13 PM
I ordered two 70 Volt Line Transformers off Ebay. Maybe I can figure out how to use one as an output for this or a similar submini amp. I'm so excited to get home and open my package and get experimentin'!
Hmmm, well this is a pedal not an amp, but it could easliy become an amp with a bit of a redesign I guess.
Quote from: frequencycentral on August 08, 2009, 02:49:32 PM
Quote from: doitle on August 08, 2009, 02:33:13 PM
I ordered two 70 Volt Line Transformers off Ebay. Maybe I can figure out how to use one as an output for this or a similar submini amp. I'm so excited to get home and open my package and get experimentin'!
Hmmm, well this is a pedal not an amp, but it could easliy become an amp with a bit of a redesign I guess.
Yeah I meant in relation to the Murder One. I realize that might be a little confusing since the thread is for the PG but me and Berger were sort of Off Topic'ing about the MO. :P
I made a PG based on Toney's vero but found it wasn't quite right. It seems it was based on an early schematic that was corrected but the vero didn't follow suit (probably why the link is dead now). Anyhow after having a super-helpful chat with Rick he sorted out where the probs were and we bodged around it. I've just fettled the vero in PhotoShop so it's a bit bodged. The wire link to C8 with the cut before it was one of the fixes we had to do. Rick says this is just for some power filtering and should really go right on the front of things so it's probably best to shift that to row 1 of the board (or the socket itself) and just run it straight to ground. As I'd already built it, I just bodged a wire in as per the diagram.
As it stands though, this puppy is now verified!
(http://farm3.static.flickr.com/2613/4082852973_0b4e02062b_o.jpg)
It's fapping loud and really very sweet. More people should build this!
(http://farm4.static.flickr.com/3532/4079721193_526430022c.jpg) (http://farm4.static.flickr.com/3532/4079721193_6d28d695f0_o.jpg)
(http://farm3.static.flickr.com/2497/4080480866_6f09d32428.jpg) (http://farm3.static.flickr.com/2497/4080480866_a2634b05c8_o.jpg)
Almost forgot, I took a pic of the board after I bodged it:
(http://farm3.static.flickr.com/2779/4082889601_ec29d046a7.jpg) (http://farm3.static.flickr.com/2779/4082889601_68aa985706_o.jpg)
Quote from: Derringer on July 07, 2009, 03:36:39 PM
damn you do nice work FC !
those tubes look like missiles ... they aren't perchance the ones that were actually used for missile guiadance are they?
The ones I used were :icon_twisted:
Well they're military spec ones at least... Mullard CV4501
...ok so they were used in radios :icon_wink:
http://www.tubecollector.org/cv4501.htm
Missiles it is!
Quote from: frequencycentral on July 16, 2009, 03:30:57 PM
For anyone who does plan to build this pedal, be aware that the 3PDT wiring really does need to be the input-grounded-when-bypassed type. I've had to change my 3PDT wiring from how it is in the photos to combat high frequency oscillation when the effect is bypassed with the gain is above 1 o'clock.
Perhaps grid stopper resistors would help to tame your oscillation problems. I've noticed that a lot of people don't use this resistor but you're using tubes that is meant to operate at up to 400 MHz. The article here (http://www.aikenamps.com/InputRes.htm) shows you how to calculate the resistance needed based off of the tube you have (it's a simple 1/(2piRC) thing).
Quote from: Cliff Schecht on November 07, 2009, 04:54:14 PM
Quote from: frequencycentral on July 16, 2009, 03:30:57 PM
For anyone who does plan to build this pedal, be aware that the 3PDT wiring really does need to be the input-grounded-when-bypassed type. I've had to change my 3PDT wiring from how it is in the photos to combat high frequency oscillation when the effect is bypassed with the gain is above 1 o'clock.
Perhaps grid stopper resistors would help to tame your oscillation problems. I've noticed that a lot of people don't use this resistor but you're using tubes that is meant to operate at up to 400 MHz. The article here (http://www.aikenamps.com/InputRes.htm) shows you how to calculate the resistance needed based off of the tube you have (it's a simple 1/(2piRC) thing).
The oscillation is completely negated by the input-grounded-when-bypassed 3PDT wiring, but yes you are right, I need to do some more delving into the mathematics which underlies electonics. Thanks for the link.
Quote from: frequencycentral on July 12, 2009, 11:38:27 AM
Hi, I'm sure John Lyons (http://www.diystompboxes.com/smfforum/index.php?action=profile;u=1334) would be more than happy to provide a PCB for you. But give it a week, as I'm in the middle of my build and need to confirm that my layout is bug-free before John makes up any PCBs.
I've already had to move C2, C9 and C14 to different locations on my perfboard to make room for the output socket - this would only matter if you plan to box it up the same way I have. I'll update the layouts anyway sometime this week.
How is the PCB? Is it bug-free? I don't have a luck with perfboard. Is there no problem if I build using the PCB, Rick??
Thank you
hey, why you don't design a head cab??? ^^
Cris
Quote from: criszou on November 23, 2009, 09:00:49 PM
How is the PCB? Is it bug-free? I don't have a luck with perfboard. Is there no problem if I build using the PCB, Rick??
I built mine on perf. I based the PCB layout on my perf layout. The perf layout is verified. If you check the PCB layout very carefully against the perf layout they should be identical. But please do check before you build, I'm only human, I make mistakes.
Quote from: criszou on November 23, 2009, 09:00:49 PM
hey, why you don't design a head cab??? ^^
http://www.diystompboxes.com/smfforum/index.php?topic=73222.0
http://www.diystompboxes.com/smfforum/index.php?topic=74786.0
http://www.diystompboxes.com/smfforum/index.php?topic=78302.0
hi, frequencycentral
I see your guts picture. What is green resistor type? it is holco or what? and the blues capacitors? double layer ceramic? what mojo you you for elco and blue capacitors?
Thank you
Rick,
Can you please specify the power rating on the resistors? I'm guessing they're 1/2 watt, but the green ones look like they might be bigger.
Dr Jones
Hi, all the resistors are 1/4 watt, the green ones are just 'recycled' from old equipment. :icon_biggrin:
Rick you asked to see it so here it is my build of your Promiscuous Girlfriend. Just a great overdrive pedal. This was my first non-kit build, and it actually worked!
(http://i878.photobucket.com/albums/ab344/toddgorman/TubeMissile.jpg)
I took the liberty of coming up with my own name, I hope you don't mind.
(http://i878.photobucket.com/albums/ab344/toddgorman/TubeMissileGuts.jpg)
Bit of a mess in here but it works.
Sorry to bump an older thread but I'm just getting into the more final stages of building this. Before beginning my wiring I realized I'd started to solder in my MAX1044 in the wrong direction. So time to check my work and ask the "there's no such thing as a stupid question" questions. This is my first tube project as well so I'm doing some new things here.
- Is there a way to confirm the pinout of the tube? the bigger 'gap' between pins I assume is the gap between pin 1 and pin 8. Pin 1 should go to square pad on the pcb, correct? so if viewed from the top, the tube's pin 1 faces towards the 'southwest' corner of the circuit board? I'd hate to get this far only to learn I'd installed the tubes wrongly just because the polarity is hard to discern.
- Are the pots in the project PDF viewed as if from the front or from the back?
Thanks for any builders of this one who can help!
strategy
The way I remember pinouts for these subminis is that there is a gap between pins 1 and 8, over than that they correspond to a dual opamp, so looking down on the tube is the same as looking down on a dual opamp (if, as I do, you create another gap between pins 4 and 5 for insertion into the PCB, SIL strips or whatever). Anyway, there's a little diagram showing the pinout in the schematic on the first page of this thread.
thanks rick,
are the pots in your pdf as though from front (turny side) or back?
thanksmuch!
strategy
Quote from: frequencycentral on March 17, 2011, 02:02:57 PM
The way I remember pinouts for these subminis is that there is a gap between pins 1 and 8, over than that they correspond to a dual opamp, so looking down on the tube is the same as looking down on a dual opamp (if, as I do, you create another gap between pins 4 and 5 for insertion into the PCB, SIL strips or whatever). Anyway, there's a little diagram showing the pinout in the schematic on the first page of this thread.
got this thing working last night- beautiful!!! tried it with guitar, synths, keyboards, drum machine...amazing!
Debugging: I can't tell if the switchable diode clipping is not working or simply very subtle. I used an SPST toggle on/off, I used 1N4148s and they are in the correct orientation. I'll check my soldering on this piece - is the diode dirt intended to be subtle or significant?
thanks much
strategy
Glad you like it. It seems to be a well kept secret. Few have built it but all seems to love it.
There's a few things you can do with the diode clipping. Reducing the 1M resistor will increase the clipping, even a pot might be useful. You can 'tune' the frequency of the clipping by changing the 0.0047uF cap value, even a 3 or 6 way cap selection switch might be useful. You'll have to experiment with values.
a 1M pot to replace that resistor or should I go for something smaller?
I feel I could have a mistake in my dirt switching. the switch seems to do almost naught. I am going to check my soldering again and maybe try a different switch...Seems you have depicted in the diagram an SPDT with one pin not connected (?) I used an SPST on/off instead. Switching always confuses me, is there really a difference between what I've done and your diagram in terms of functionality?
thank you Rick for this fun circuit
I'll post my build in which I used a sloping LMB enclosure and drilled reveals so that I could have visual and heat venting while not having my tubes poke out of the enclosure...Its almost done...very industrial looking but crafted
Strategy
Quote from: Strategy on May 14, 2011, 02:14:56 AM
a 1M pot to replace that resistor or should I go for something smaller?
It's been a couple of years since I made that pedal, and I don't own it anymore. I'd suggest installing sockets for the resistor and cap. That way you can play around with values until you hit on perfection. You will probably find that the optimal for replacing the 1M is a resistor and pot in series, so you have at least some minimum of resistance (which you will certainly need). But yeah, try a 1M pot, see how useful it is at either end of it's throw, measure it.........you *might* end up with a 500k pot and a 220k resistor in series (for example).
A little resoldering got the dirt switch operational. I'll try the socketing after I know this thing is stable.
So, I started the 'boxing it up process' and had to stop mid way as I mis-drilled my enclosure and I'd rather start again than have something with wrong holes. In any case I have some trouble shooting to do:
Surprise #1:
I hadn't soldered the MAX1044 all the way in! When I tested it it worked great so I assume that it had enough contact to work fine. Fortunately it wasn't on for very long this way. Less than 5 minutes. Promptly soldered it all up before powering it on for the second test!
Surprise #2:
There's a low-mid, steady hum at all times which becomes more present as I increase the volume knob. I've gone back and checked for grounding and continuity issues and can't seem to locate it.
This is my first tube project:
Could this be a tube issue?
Is this normal and I'm just cranking it so high the noise floor is abnormally strong sounding?
Is this pedal best served by shielded inputs and outputs wiring?
Thanks for the help with this- really wanting to get this one going
Strategy
bump - anyone else get hum? increases with use of volume knob?
doesn't sound quite like ground hum?
as a tube noob, any advice would be appreciated!
strategy
Hum. 99% possibility that it's coming from your power supply. Tube heaters are sensitive to unregulated/poorly regulated supplies. You could try a big ass electro cap across the supply rails. Or powering from a higher voltage PSU (15v) via a 7812 with a 100uF cap at it's input and output.
hmmm...I'm using this:
http://www.smallbearelec.com/Detail.bok?no=1006 (http://www.smallbearelec.com/Detail.bok?no=1006)
Not good enough? Can anyone stateside tell me a wallwart that might be preferable?
Strategy
Quote from: Strategy on May 19, 2011, 03:53:32 PM
hmmm...I'm using this:
http://www.smallbearelec.com/Detail.bok?no=1006 (http://www.smallbearelec.com/Detail.bok?no=1006)
Not good enough? Can anyone stateside tell me a wallwart that might be preferable?
Strategy
Although Steve sells many wall warts at a good price.... alas they are NOT regulated.
I could suggest a 1Spot. They are very quiet. Just give them some time between unplugging them and handling the contacts :icon_lol:
how do you get the "tube guards" on the enclosures?!
Quote from: Govmnt_Lacky on May 19, 2011, 04:19:21 PM
I could suggest a 1Spot.
I use a 1spot and like it, but this project requires 12v which the 1spot cannot supply, so it's not an option here.
Quote from: Seven64 on May 19, 2011, 04:58:04 PM
how do you get the "tube guards" on the enclosures?!
Bolted on from below of course. One short pair of bolts, another long pair with 15mm M4 nylon spacers to mount the circuit board. It's how I do my amps too.
Quote from: Taylor on May 19, 2011, 05:16:04 PM
Quote from: Govmnt_Lacky on May 19, 2011, 04:19:21 PM
I could suggest a 1Spot.
I use a 1spot and like it, but this project requires 12v which the 1spot cannot supply, so it's not an option here.
Might be easier to us an AC supply, rectified, filtered and regulated.
i should have re-worded that.
what are they exactly? just stainless steel tubing or something like that?
Quote from: Seven64 on May 19, 2011, 05:19:13 PM
i should have re-worded that.
what are they exactly? just stainless steel tubing or something like that?
They are drawer handles. Bought from B&Q in the UK. Sorry to compromise the mystique. :D
Here's another PG based pedal, with Vox tonestack and Bblender:
(http://dl.dropbox.com/u/967492/Moon%20Unit/Moon%2001.jpg)
(http://dl.dropbox.com/u/967492/Moon%20Unit/Moon%2002.jpg)
Jameco seems to have linear regulated 12V supplies of various sorts as wall wart.
Confirming from my last post, 12V linear regulated Jameco wall wart works...HUM FREE!
As soon as my enclosure gets here this baby will be ready to go...pics to come!
Strategy
^^^ Cool! 8)
Here's a soundclips of the Moon Unit (pics above) done by it's new owner:
OK finally got this one off the ground! Sounds great and full build pics here
http://www.diystompboxes.com/smfforum/index.php?topic=36392.msg788305#msg788305 (http://www.diystompboxes.com/smfforum/index.php?topic=36392.msg788305#msg788305)
^^^
Looks really good Strategy!
Here's my next one:
(http://dl.dropbox.com/u/967492/Kreken/Kreken%20top.jpg)
(http://dl.dropbox.com/u/967492/Kreken/Kreken%20front.jpg)
(http://dl.dropbox.com/u/967492/Kreken/Kreken%20side%202.jpg)
Hey Rick,
I was wondering if you might share the mods you did to the PG for a bass. I really wanna build one like the "Moon Unit" that sound is awesome. This will be my second build and my first at a stompbox. Any layouts or schematics would greatly help.
Thanks
-Josh
+1 for the bass mods. I read Kevin's review on Talkbass and I would love to build the "Moon Unit" version as well.
......it's evolved.....
(http://dl.dropbox.com/u/967492/BOD/bod4.jpg)
......and evolved.....
(http://dl.dropbox.com/u/967492/Demon%20Cleaner/DC01.jpg)
......it's evolved.....
(http://dl.dropbox.com/u/967492/OD%20Zilla/ODzilla%201.jpg)
......and evolved.....
(http://dl.dropbox.com/u/967492/Mission%20Control/MC%20Detail.jpg)
......forgive me for keeping some secrets....
Aw shucks. I thought you might say that, but I completely understand. Those builds are beautiful, by the way. Very inspiring. Keep up the good work, and let me know if you change your mind. :icon_wink: