Jaicen Posted January 23, 2013 Share Posted January 23, 2013 You know what you should do there given that you have those ridiculously over specced caps? Piggyback 12v transformers and run that tube on the voltage it was designed for instead of starving the plates. That will sound so much better. Link to comment Share on other sites More sharing options...
Don'tPostThePear Posted January 23, 2013 Share Posted January 23, 2013 the cornish guy specified the sweetspot at 450 or something like that for muff tranny hfe. i can find it for you james but personally i wouldnt give a fuck. also 2n5088 or bc548 or etc. doesn't matter. the gain is fixed anyways by the bias resistors plus the diodes will clip much sooner than the trannies. tonestack makes the most difference, then the caps between the gainstages and the caps around the clipping diodes (by filtering out the low frequencies so they wont get clipped making your shit a bit more clear) i wouldnt mess with the diodes, not worth it. also most of them sucks, the only bearable muff for me is the IC version. tailor your tonestack to your amp ang git and taste and you will be fine. Link to comment Share on other sites More sharing options...
james90 Posted January 23, 2013 Share Posted January 23, 2013 You know what you should do there given that you have those ridiculously over specced caps? Piggyback 12v transformers and run that tube on the voltage it was designed for instead of starving the plates. That will sound so much better. What voltage is the 12AU7/ECC82 meant to run on? Here's what I'm building http://www.beavisaudio.com/projects/ValveCaster/ although I might change the input cap to a lower value... it sounds pretty dark in other peoples' recordings the cornish guy specified the sweetspot at 450 or something like that for muff tranny hfe. i can find it for you james but personally i wouldnt give a fuck. also 2n5088 or bc548 or etc. doesn't matter. the gain is fixed anyways by the bias resistors plus the diodes will clip much sooner than the trannies. tonestack makes the most difference, then the caps between the gainstages and the caps around the clipping diodes (by filtering out the low frequencies so they wont get clipped making your shit a bit more clear) i wouldnt mess with the diodes, not worth it. also most of them sucks, the only bearable muff for me is the IC version. tailor your tonestack to your amp ang git and taste and you will be fine. alrighty then What years was the IC version made? Was that late 70's? The best sounding one I've owned was a late 70's, but I don't know what was going on inside.... it was modded for true bypass, and had a tone control bypass switch, but otherwise was stock. Link to comment Share on other sites More sharing options...
Jaicen Posted January 23, 2013 Share Posted January 23, 2013 the cornish guy specified the sweetspot at 450 or something like that for muff tranny hfe. i can find it for you james but personally i wouldnt give a fuck. also 2n5088 or bc548 or etc. doesn't matter. the gain is fixed anyways by the bias resistors plus the diodes will clip much sooner than the trannies. tonestack makes the most difference, then the caps between the gainstages and the caps around the clipping diodes (by filtering out the low frequencies so they wont get clipped making your shit a bit more clear) i wouldnt mess with the diodes, not worth it. also most of them sucks, the only bearable muff for me is the IC version. tailor your tonestack to your amp ang git and taste and you will be fine. QFT, except the bit about the IC Muff, cos that just sucks. Funny story re: Pete Cornish. I remember he used to hang out on the diy stompbox message board back in the day when it was on Ampage. He 'contributed' (ie, suggested things people should try) to the community working on the Muff, testing all sorts of stuff, then basically put it all into 'his' pedal (Creamy Dreamer?). Caught a lot of flak for it too, but that was what, 15 years ago? Anyway, if I remember correctly, back then he was adamant that you want to put .01uF caps between stages and use 200hfe transistors for topmost mojo. I agree to an extent, but I still think the value is in the tonestack. Oh, the 12AX7 wants ~220v. Check out some stuff on AX84.com, there's a few pre-amps on there that may look familiar. Link to comment Share on other sites More sharing options...
Neil. Posted January 24, 2013 Share Posted January 24, 2013 You know what you should do there given that you have those ridiculously over specced caps? Piggyback 12v transformers and run that tube on the voltage it was designed for instead of starving the plates. That will sound so much better. What voltage is the 12AU7/ECC82 meant to run on? 6V/12V to the heater (depending on how you wire it up) and with the anode, yeah you want at least 100V (silvertoanzz) or more for it. They can take massive voltages at the anode. I have a vague recollection of Mesa sending something like 450V to the anode on one of their amps, possibly the Mark II. If you want to see some really creative ways of giving 12AX7s some decent voltages, look up a guy called "FrequencyCentral." He uses a clever little Nixie SMPS to go from 9-12V up to around 100-200V. I tried it out before and it works excellently, but it's a very very delicate power supply solution. It might be something to hang on a bit for when you're a bit more experienced with circuits. I don't mean that in a bad way, but it's something to work towards. Link to comment Share on other sites More sharing options...
james90 Posted January 24, 2013 Share Posted January 24, 2013 6V/12V to the heater (depending on how you wire it up) and with the anode, yeah you want at least 100V (silvertoanzz) or more for it. They can take massive voltages at the anode. I have a vague recollection of Mesa sending something like 450V to the anode on one of their amps, possibly the Mark II. If you want to see some really creative ways of giving 12AX7s some decent voltages, look up a guy called "FrequencyCentral." He uses a clever little Nixie SMPS to go from 9-12V up to around 100-200V. I tried it out before and it works excellently, but it's a very very delicate power supply solution. It might be something to hang on a bit for when you're a bit more experienced with circuits. I don't mean that in a bad way, but it's something to work towards. Any idea how that dickinson pedal was setup? I know there was a small transformer inside of it, but otherwise, I couldn't identify anything besides the big pretty orange caps And I have a Mark II... tempted to measure some voltages now. Link to comment Share on other sites More sharing options...
james90 Posted January 24, 2013 Share Posted January 24, 2013 ffs just got the electrolytics in, but since the board was designed with film caps in mind in those positions, it doesn't say which way they go in seems like it's more trouble than it's worth to figure it out, so i think i'll just buy some non polarized electrolytics or do these sound noticeably different than polarized ones? Link to comment Share on other sites More sharing options...
Jaicen Posted January 24, 2013 Share Posted January 24, 2013 You want ~230v for those 12ax7's and 12v dc for the heaters. Supply it with 12vAC, rectify for heaters, plug the SECONDARY of a 12v 500ma transformer to the 12v AC. From the primary of that transformer, you will have around 220v. Rectify, filter and plug into your tubes. Simples. Link to comment Share on other sites More sharing options...
james90 Posted January 25, 2013 Share Posted January 25, 2013 so... one problem though: one of my white circles came off do i need that there or is it just to help with soldering? the part is still soldered in place, but i don't know if it needs to be there to connect with something else Link to comment Share on other sites More sharing options...
james90 Posted January 25, 2013 Share Posted January 25, 2013 a few more bits came in the mail post today, so i'm really only waiting for the non polarized caps (I did get the polarized ones, but I'm not going to bother) and a 220pf ceramic cap Then I can finish it. I don't know about the white circle though... would there be a trace connecting those two solder joints that I can't see? Or should I just bridge them somehow from the outside? because it DOES look like those two are supposed to be connected I've also taken on another amp project... only problem is that there aren't any schematics of this amp available ANYWHERE (not that I know how to read them properly!) shouldn't be too difficult though as it's pretty much stock and does function... Only issue I've found was that someone bypassed the presence control (wtf?) which made it sound... bad. PCB needs a bit of cleaning up too as something blew up in there at one point. Link to comment Share on other sites More sharing options...
Dave. Posted January 25, 2013 Share Posted January 25, 2013 Took apart my Nano Clone (was total fucked). I'll use the box for my bazz fuss. There are a few other parts I can save. The jacks, they're fine. The switch, a nice 3x3 one (the name escapes me). The 9V power input, the LED and the pot. The pot reads "1M c". I know what the 1M means but what about the c? Can I use it in my Bazz fuss? Link to comment Share on other sites More sharing options...
Crowella Posted January 25, 2013 Share Posted January 25, 2013 Took apart my Nano Clone (was total fucked). I'll use the box for my bazz fuss. There are a few other parts I can save. The jacks, they're fine. The switch, a nice 3x3 one (the name escapes me). The 9V power input, the LED and the pot. The pot reads "1M c". I know what the 1M means but what about the c? Can I use it in my Bazz fuss? 1MC stands for 1 Mega Ohm resistance with a C taper which means reverse log taper. If you are saying the pedal was fucked, I wouldn't be using that pot in there anyway. Also because unless you wire the pot backwards (where it will operate backwards), you will have troubles with controlling volume since reverse log is the last thing you want to use for volume control. Volume control is normally done with an Audio taper, or A taper, unless your ZVex and you cheap out on parts (clever) by using a standard linear, or B taper. The 3x3 switch is called a 3PDT which means three poles, two throw. That's perfect for true bypass with LED. The 9V power input will be ideal also and so should the LED. Just remember that the LED needs a resistor wired up so you don't blow the LED up. Does the Nano Clone have a battery clip? Link to comment Share on other sites More sharing options...
Dave. Posted January 25, 2013 Share Posted January 25, 2013 1MC stands for 1 Mega Ohm resistance with a C taper which means reverse log taper. If you are saying the pedal was fucked, I wouldn't be using that pot in there anyway. Also because unless you wire the pot backwards (where it will operate backwards), you will have troubles with controlling volume since reverse log is the last thing you want to use for volume control. Volume control is normally done with an Audio taper, or A taper, unless your ZVex and you cheap out on parts (clever) by using a standard linear, or B taper. The 3x3 switch is called a 3PDT which means three poles, two throw. That's perfect for true bypass with LED. The 9V power input will be ideal also and so should the LED. Just remember that the LED needs a resistor wired up so you don't blow the LED up. Does the Nano Clone have a battery clip? Ok so I'll leave the Pot then It does have a battery clip so I'll take that as well. At least I can salvage a few parts from this hunk of crap. Seriously, if anyone of ye is thinking of buying a Nano Clone, DON'T! Neo's are much better. Would you be able to suggest a particular set-up for the sound I want? I'm looking for an almost synth like fuzz, thick and deep (lolstenhome style). Mainly because I like synth bass sounds in rock songs. Link to comment Share on other sites More sharing options...
Crowella Posted January 25, 2013 Share Posted January 25, 2013 Ok so I'll leave the Pot then It does have a battery clip so I'll take that as well. At least I can salvage a few parts from this hunk of crap. Seriously, if anyone of ye is thinking of buying a Nano Clone, DON'T! Neo's are much better. Would you be able to suggest a particular set-up for the sound I want? I'm looking for an almost synth like fuzz, thick and deep (lolstenhome style). Mainly because I like synth bass sounds in rock songs. I built this one below and I can recommend it. For that kind of fuzz, you would either use a 1N914 diode or even a Red LED in place of it. I would also recommend that for the transistor you do use the MPSA13. I've tried a single 2N5088 there but I found it slightly disappointing. It's not going to be thick like say, a Woolly Mammoth but you'll get a fuzz that sits down low quite nicely. Link to comment Share on other sites More sharing options...
Dave. Posted January 25, 2013 Share Posted January 25, 2013 I built this one below and I can recommend it. For that kind of fuzz, you would either use a 1N914 diode or even a Red LED in place of it. I would also recommend that for the transistor you do use the MPSA13. I've tried a single 2N5088 there but I found it slightly disappointing. It's not going to be thick like say, a Woolly Mammoth but you'll get a fuzz that sits down low quite nicely. Fantasic Where does the switch go? Link to comment Share on other sites More sharing options...
Crowella Posted January 25, 2013 Share Posted January 25, 2013 Fantasic Where does the switch go? I was about to write up how to do it but this might be more help for switching. Just find the one in there you want. https://www.generalguitargadgets.com/tech-pages/51-switching-and-wiring The input here is the before first capacitor on the left and the output is where the middle lug of the pot goes. Link to comment Share on other sites More sharing options...
matthijs Posted January 27, 2013 Author Share Posted January 27, 2013 Just found the Boss OC-2 synth mod... now that looks and sounds really cool! Link to comment Share on other sites More sharing options...
james90 Posted January 27, 2013 Share Posted January 27, 2013 it doesn't work I don't even know where to start troubleshooting Link to comment Share on other sites More sharing options...
tomrulez Posted January 27, 2013 Share Posted January 27, 2013 it doesn't work I don't even know where to start troubleshooting Get yourself an audio probe built Link to comment Share on other sites More sharing options...
james90 Posted January 28, 2013 Share Posted January 28, 2013 i had one of those in kit form from BYOC, and finally assembled it this morning I couldn't figure out the problem... I was getting a good signal up until around Q3. I had them installed backwards at first (obviously), but they're installed correctly now. all pins of Q1 and Q2 were giving me a signal, but not Q3 http://www.generalguitargadgets.com/diagrams/bmpsc.gif It's something right after R13 from what I can tell...everything after that was dead, although I'm pretty sure C8 and R15 were working I replaced EVERY component in that area (including Q3), and no luck. I'm not sure if the transistors were bad for whatever reason, but I do have some from a different source that I might try. I do get a bit of static when I turn the tone control as well, which makes me think that part is working properly... Link to comment Share on other sites More sharing options...
Jaicen Posted January 28, 2013 Share Posted January 28, 2013 i had one of those in kit form from BYOC, and finally assembled it this morning I couldn't figure out the problem... I was getting a good signal up until around Q3. I had them installed backwards at first (obviously), but they're installed correctly now. all pins of Q1 and Q2 were giving me a signal, but not Q3 http://www.generalguitargadgets.com/diagrams/bmpsc.gif It's something right after R13 from what I can tell...everything after that was dead, although I'm pretty sure C8 and R15 were working I replaced EVERY component in that area (including Q3), and no luck. I'm not sure if the transistors were bad for whatever reason, but I do have some from a different source that I might try. I do get a bit of static when I turn the tone control as well, which makes me think that part is working properly... Ok, check voltages on R17 and R14. If R14 is shorted to ground, it will kill your signal. Likewise, if R17 is too small it will kill your signal. If R17, R14 or R16 are missing, the transistor will fail to bias correctly and won't output a signal. My gut feeling is that you have a short to ground after R13 which is bleeding the signal to ground. If you have replaced components, it's most likely a solder bridge. Get a magnifier and check all your solder joints. Static noise on a pot means there's DC on it, which means you're probably wired it wrong. EDIT: Can you put up some pics of both sides of your board? Link to comment Share on other sites More sharing options...
james90 Posted January 28, 2013 Share Posted January 28, 2013 I really should clean it up before doing that! From earlier with the audio probe, I wrote down that R17 and R16 were completely dead (nothing through the amp) but a slight bit of signal was coming through R14 also, how small is too small for R17? Neil said to use 10k Link to comment Share on other sites More sharing options...
Jaicen Posted January 28, 2013 Share Posted January 28, 2013 10k is fine. Link to comment Share on other sites More sharing options...
Neil. Posted January 29, 2013 Share Posted January 29, 2013 jaeaaeemzs check the pinout on the transistors vs the orientation on the board. I can't even tell you how many times I had muffs not working from that. Link to comment Share on other sites More sharing options...
james90 Posted January 29, 2013 Share Posted January 29, 2013 I did - I had them installed wrong at first, but they're in the correct way now Link to comment Share on other sites More sharing options...
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