tag:blogger.com,1999:blog-6847048658257278783.post701700307248107375..comments2024-03-29T01:36:12.851+00:00Comments on Guitar FX Layouts: Xotic BB PreampIvIarkhttp://www.blogger.com/profile/08416945174853142251noreply@blogger.comBlogger112125tag:blogger.com,1999:blog-6847048658257278783.post-61102575863659395372022-12-09T20:30:29.088+00:002022-12-09T20:30:29.088+00:00Have you tried c1815 instead of 2n5088?Have you tried c1815 instead of 2n5088?onurB onaczuChttps://www.blogger.com/profile/03396415826764798450noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-61872413629625236792022-02-12T17:29:56.143+00:002022-02-12T17:29:56.143+00:00Anyone else had that same problem as me? - all my ...Anyone else had that same problem as me? - all my voltages check out, but I have a constant, loud, low pitched hum that I've not experienced before (built close to a hundred pedals) - is this what DC sounds like when it's getting into the signal?Paul_510https://www.blogger.com/profile/09317116587026791629noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-45241918087457208942019-05-01T09:01:25.845+01:002019-05-01T09:01:25.845+01:00Blimey - just finished a build and de-bugging proj...Blimey - just finished a build and de-bugging project on this and it sounds absolutely amazing. I have the BB+ and have previously owned the BB - sold it to cover the rent!<br /><br />The clipping options switch opens up a massive range of tones and frankly, what I've ended up with sounds every bit as good as the genuine article but probably with more tonal options, to my ears.<br /><br />Having already knocked myself out with the Jan Ray that came off the line yesterday, I am now in overdrive heaven.<br /><br />Many thanks, Ivlark and friends - you are making an old fart feel accomplished and happy :)<br />Millibobshttps://www.blogger.com/profile/02675003289482607445noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-29765670623750762952019-04-18T19:45:22.325+01:002019-04-18T19:45:22.325+01:00Would it be a good idea to use LEDs as clipping?Would it be a good idea to use LEDs as clipping?cacopandahttps://www.blogger.com/profile/17903314093674324849noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-42711944864766612512019-01-08T09:12:36.595+00:002019-01-08T09:12:36.595+00:00Read this schematic:
http://johnkvintageguitars.ho...Read this schematic:<br />http://johnkvintageguitars.homestead.com/Effects/Fuzz-ODs/BBpreamp/BBschematic2.png<br /><br />The BB Preamp has alredy the "more gain mod". Remember it's similar enough to a Tube Screamer.<br />The only thing you could try is change the 4.7k resistor (R6), the one to the right of the lower IC. Reducing it to 2.4k or 1k you should increase the gain, but even change the clipping frequency, maybe you should increase a bit the 47nF (C4) next to the "Sw1-5" wire, too.<br /><br />Then, I'm not sure, but maybe you could try to increase 1k resistor R11 and 47k R16. I expect that increase the gain, but I could wrong.<br /><br />And the last thing I think is to increase the gain of the input stage, maybe using and high hfe transistor (MPSA18?) or change some resistor value (R3?).Elijah-Baleyhttps://www.blogger.com/profile/16374916649117645180noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-61643342625085949972019-01-08T09:11:40.778+00:002019-01-08T09:11:40.778+00:00This comment has been removed by the author.Elijah-Baleyhttps://www.blogger.com/profile/16374916649117645180noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-44681251449608178412019-01-08T01:23:19.423+00:002019-01-08T01:23:19.423+00:00I build it for bass, so i did some mod for adjustm...I build it for bass, so i did some mod for adjustment. Replace 22n cap to 220n on input section. Remove 33n (2 caps) on bass control and replacing with 100n. Then remove 4n7 (2 caps) on treble and replacing with 10n. It works well, but there's any mod to increase gain? any advice?Zoedroonhttps://www.blogger.com/profile/11463135639796291199noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-1682467548256615392018-11-21T15:03:05.415+00:002018-11-21T15:03:05.415+00:00The new versions of AC, RC and BB seem to have one...The new versions of AC, RC and BB seem to have one additional transistor, maybe a FET that's part of the clipping circuit. Does anybody have a schematic or could draw one? https://musikding.rocks/wbb/index.php/Attachment/420299-AC-detail-5-800x600-jpg/Mr.Baiserhttps://www.blogger.com/profile/11045675646569701854noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-40216217020152437392018-08-21T20:14:28.854+01:002018-08-21T20:14:28.854+01:00Have you tried this thing called the internet?
+mHave you tried this thing called the internet?<br />+mmirosolhttps://www.blogger.com/profile/02400327798106357876noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-12589671092463263022018-08-17T17:36:44.794+01:002018-08-17T17:36:44.794+01:00Where can I find the schematic?Where can I find the schematic?Anonymoushttps://www.blogger.com/profile/11333582226923802756noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-83529526607276425272016-12-23T16:34:43.835+00:002016-12-23T16:34:43.835+00:00This comment has been removed by the author.Anonymoushttps://www.blogger.com/profile/16606980232763280183noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-28122624133186756022016-11-07T22:18:04.690+00:002016-11-07T22:18:04.690+00:00Hey mdtcarroll -
I've built three of thes...Hey mdtcarroll -<br /> I've built three of these and one of the three does the squealing with the treble and gain maxed...the 51p is the one you want to increase (or at least the one I've increased) to eliminate that squeal. The clipping amp is the IC more central to the layout...the one where pin 1 is in the row connected to the Drive 1 pot lug. The ceramic cap in question is in that row as well. <br /><br />I've increased it to about 94p (running two 47p in parallel) and that seemed to do it for me. My concern, however, is the change in the rolloff frequency created by that capacitor in particular. If my calculations are correct using the formula found here (http://www.electrosmash.com/tube-screamer-analysis) for a tubescreamer (the BB is essentially a tubescreamer followed by a good active two band eq), I find that with the gain maxed and the 51p being used, the rolloff frequency for the clipped waveform to be just a tad higher than 3K (the original tubescreamer with the smaller value pot and higher value resistor have it at around 5.6k).<br /><br />Increasing that 51p decreases the rolloff frequency of the low pass filter. Changing it to 94p decreases the frequency to 1.6K and changing it to a 220p creates a rolloff frequency of about 700hz. I'm curious as to whether or not most people can hear that change of if I've got my math all wrong and don't know what the heck I'm saying 'cause I don't quite understand the analysis of it all (quite possible).Benhttps://www.blogger.com/profile/02644344177589539278noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-56391248674913463922016-09-20T13:11:39.243+01:002016-09-20T13:11:39.243+01:00I'm also a little confused from the threads ab...I'm also a little confused from the threads above w.r.t. changing the ceramic cap value in the clipping amp. There is reference to the 51p and also the 151p. i.e. swapping for a ~ 220p. Are you able to point out the cliipping amp and which of those 2 values should be increased to 220p please?Anonymoushttps://www.blogger.com/profile/02386829770603458381noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-11938434699918363902016-09-20T13:06:46.499+01:002016-09-20T13:06:46.499+01:00Thanks!Thanks!Anonymoushttps://www.blogger.com/profile/02386829770603458381noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-17433981003155411702016-09-12T03:47:49.740+01:002016-09-12T03:47:49.740+01:00No. You can use a connection to led+ from the boa...No. You can use a connection to led+ from the board if convenient or just wire per off board. B. Younghttps://www.blogger.com/profile/13641709644991822510noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-17602790100086251812016-09-12T00:57:09.866+01:002016-09-12T00:57:09.866+01:00Sorry, to clarify....Does that mean there are 2 co...Sorry, to clarify....Does that mean there are 2 connections at the physical LED+ ?Anonymoushttps://www.blogger.com/profile/02386829770603458381noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-31068651125632825892016-09-12T00:54:54.064+01:002016-09-12T00:54:54.064+01:00Hi There, Just a bit confused by the LED+ wire fro...Hi There, Just a bit confused by the LED+ wire from the board. Does that mean there are 2 connections at the LED+ when using the Offboard wiring diagram shown on this site?Anonymoushttps://www.blogger.com/profile/02386829770603458381noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-90718534045978017352016-04-29T12:23:39.647+01:002016-04-29T12:23:39.647+01:00I have already posted my issues there, sorry.... I have already posted my issues there, sorry.... Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-7869335792097575592016-04-29T12:22:33.453+01:002016-04-29T12:22:33.453+01:00Mr Mirosol, if you don't mind, could you pleas...Mr Mirosol, if you don't mind, could you please help me out on my suhr build please? <br /><br />Many thanks in advance!Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-1864906106592019492016-04-29T11:35:20.792+01:002016-04-29T11:35:20.792+01:00No worries. Go ahead and try to lower that value. ...No worries. Go ahead and try to lower that value. Has worked for me on a few BB builds... :)<br />+mmirosolhttps://www.blogger.com/profile/02400327798106357876noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-52283380727194393272016-04-29T11:28:22.517+01:002016-04-29T11:28:22.517+01:00Thanks for your prompt reply. I did read the whole...Thanks for your prompt reply. I did read the whole comment section before I ask but since I am not as experience as you guys, I didn't realise that the ocsillation and 47k issues are what i am experiencing... <br /><br />thank ou so much again, I will do what you said. keep learning! cheers! Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-63015782934525910642016-04-29T11:01:01.910+01:002016-04-29T11:01:01.910+01:00There is already a comment here about the behaviou...There is already a comment here about the behaviour you're experiencing. The layout is per the schematic that was up in german DIY forum and thus, there is a slight error. The upper right side. There is a 47K resistor. Lower that value to something like 18K, 22K or 27K. As stated, that resistor is 16K in Madbean's documents for his version. 47K takes out too much gain for that opamp half, which causest that part of the circuit to oscillate. You could also up the 151p for 200-220pF.<br />+mmirosolhttps://www.blogger.com/profile/02400327798106357876noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-45019028744520324772016-04-29T10:43:53.672+01:002016-04-29T10:43:53.672+01:00It sounds better than my suhr riot build, which th...It sounds better than my suhr riot build, which the sound is a bit loose, dull and cuts out a lot of high end frequency.<br /><br />For this one,I get a high pitched noise when I turn up the treble and bass... which cap or caps can I change in order to elimilate it?<br /><br />also, the B1M "gain" doesn't seem to make obvious difference in terms of distortion. my problem?<br /><br />any advise will be appreciated.Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-66576137857361278102016-04-22T18:17:32.287+01:002016-04-22T18:17:32.287+01:00What schematic did you use in this layout? What schematic did you use in this layout? giudishttps://www.blogger.com/profile/03947795301633910036noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-77811108595403263222016-04-22T18:17:19.873+01:002016-04-22T18:17:19.873+01:00What schematic did you use in this layout? What schematic did you use in this layout? giudishttps://www.blogger.com/profile/03947795301633910036noreply@blogger.com