tag:blogger.com,1999:blog-6847048658257278783.post2913054327090270769..comments2024-03-27T15:26:01.893+00:00Comments on Guitar FX Layouts: Catalinbread CB30IvIarkhttp://www.blogger.com/profile/08416945174853142251noreply@blogger.comBlogger57125tag:blogger.com,1999:blog-6847048658257278783.post-73157367089428742162017-11-21T03:52:56.630+00:002017-11-21T03:52:56.630+00:00Very late to the game here, but I wanted to contri...Very late to the game here, but I wanted to contribute some findings I stumbled upon with this build. <br /><br />It seems like low volume is a very common complaint with this build (and also the first version of the Galileo), and one that I also encountered. I couldn't find any well-described solutions here, @ FSB, or elsewhere on the inter web; some people seemed to have luck with the circuit, and others didn't. There seem to be some circuit tweaks floating around the web, but I think the circuit is pretty well correct as Mark laid out here. <br /><br />I think that the role (and particularly the biasing) of the 2N5457 trannies has been underestimated. I couldn't find any info on biasing 2N5457s that was useful to a relative noob like myself. Luckily I had about twenty 2n5457s to experiment with, and i ended up ranking them all by drain voltage (relative to ground) when in the Q1 position (I just left everything the same in the circuit and swapped out each tranny in the socketed Q1, one at a time, and recorded the drain voltage of each of the transistors). I found that if relatively low drain-voltage transistors are placed in Q2 and Q4, and relatively high drain-voltage transistors are placed in Q1 and Q3, there is a tonne of volume to be had (with gain full CCW, and volume full CW, it is much, much louder than unity). With that combo, the lower mids are really pushed, and the circuit sounds a bit boomy and muffled, and also has too much gain that can't really be tamed with the guitar vol knob. If I reversed that, and put the low drain-voltage transistors in Q1 and Q3, and the high drain-voltage transistors in Q2 and Q4, the circuit was really quiet and anaemic, with much lower volume than unity when the gain/vol settings were as described above. <br /><br />What sounded best to me was putting my lowest drain-voltage transistors in Q1, Q2 and Q4, and one of the highest drain voltage transistors in Q3. The EQ is still mids-forward, but very manageable with the EQ, and the gain was easily tamed by backing off on the guitar volume. The circuit actually sounds pretty awesome, and still has plenty of volume on tap. Incidentally, this is the first pedal that sounds good with my germanium rangemaster clone pushing it!<br /><br />I'm sure someone out there understands what's going on. I've biased J201s before to half the supply voltage, but in this case, the maximum volume of the circuit i obtained was when I was getting drain voltage readings >6V at Q1 and Q3. I'd love to hear anyone's thoughts on this if it makes sense to them! Anonymoushttps://www.blogger.com/profile/06690829307177426960noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-9390423616359026152016-06-21T13:47:13.324+01:002016-06-21T13:47:13.324+01:00I had the same problems with volume as many of you...I had the same problems with volume as many of you. After few days of experimentations, I found that my pedal works best with these changes: <br /><br />http://i65.tinypic.com/2rdj9ld.png <br /><br />Changed gain and volume pots to anti-log, Q2 470pf capacitor to 10nf as someone suggested, jumpered 4.7k going to volume 3, input cap from foil to electrolytic as in original, 220nf foil film cap on Q4 to electrolytic (both caps positive side oriented to top side of layout). <br /><br />Cheers!!!Fecalius Vandalehttps://www.blogger.com/profile/10949712634316549046noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-84683750216673089222016-01-20T14:11:10.541+00:002016-01-20T14:11:10.541+00:00This comment has been removed by the author.Anonymoushttps://www.blogger.com/profile/03786528896050022425noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-47220684152260251472015-10-04T05:08:30.229+01:002015-10-04T05:08:30.229+01:00100k at input dropped to 10k, 47n for 22n on Q2, s...100k at input dropped to 10k, 47n for 22n on Q2, skipped 200k altogether following EQ, used J201 @ Q5 - better performance with 18v supply; works a treat with already built treble boost ( Ge Dallas Rangemaster )Pete ROGERShttps://www.blogger.com/profile/08763429281192727968noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-76699519327004209682015-07-14T21:13:55.784+01:002015-07-14T21:13:55.784+01:00Does this one have the same low volume issues that...Does this one have the same low volume issues that the Galileo? I had built the Galileo but at max vol it is only a bit above unity. I thought about building this with a full naga in front but don't want to bother if it's basically the same on the CB30 side of the circuit. Thanx for any info.Synsoundhttps://www.blogger.com/profile/14024171751270017980noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-39449347047589129152014-07-29T18:57:24.453+01:002014-07-29T18:57:24.453+01:00I still can't get this one. Everything looks c...I still can't get this one. Everything looks correct. I triple check it. The only thing I can think of is a faulty componet or something. If anyone can help, that would be awesome! I posted my voltages in the above comments. MadWagnerhttps://www.blogger.com/profile/01829209684898478688noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-51598119521946068812014-07-29T05:34:54.284+01:002014-07-29T05:34:54.284+01:00Thanks John! I got my probe out. And I am losing s...Thanks John! I got my probe out. And I am losing signal at the 330pf cap. I replaced the cap but still am losing signal. If I pull Q1 I can keep probing past 330pf. I'm still stumped, with this one.MadWagnerhttps://www.blogger.com/profile/01829209684898478688noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-87259657819333635882014-07-29T04:23:27.354+01:002014-07-29T04:23:27.354+01:00if you don't have a scope to do a signal trace...if you don't have a scope to do a signal trace, i'd start looking for a misplaced component or link.johnkhttps://www.blogger.com/profile/00643996045674470081noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-57432012471238146432014-07-29T04:01:26.263+01:002014-07-29T04:01:26.263+01:00thanks for the reply! I checked every thing and ca...thanks for the reply! I checked every thing and can't find any solder bridges. I pretty stumped on this. Is there any other suggestions, where I should start debugging?MadWagnerhttps://www.blogger.com/profile/01829209684898478688noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-89454137899281057312014-07-29T03:09:28.885+01:002014-07-29T03:09:28.885+01:00You shouldn't have anything like 7.2V on your ...You shouldn't have anything like 7.2V on your sources, I think you need to check over your connections, check cuts are complete and no burrs and creating shortsIvIarkhttps://www.blogger.com/profile/08416945174853142251noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-38545851492404252532014-07-29T00:53:06.590+01:002014-07-29T00:53:06.590+01:00I got rid of the whine noise. It was my power supp...I got rid of the whine noise. It was my power supply. But I'm still not getting any sound. My transistor voltages are: <br />Q1 Gate:5.0 Source:7.2 Drain7.2 Q2 Gate:3.16 Source: 7.2 Drain: 9.46 Q3 Gate: 3.30 Source: 7.19 Drain:6.17 Q4 Gate: 3.14 Source: 6:17 Drain: 9.46 Q5 Gate 3.72 Source 9.41 Drain 9.46 <br />If any one can help, it would be much appreciated. <br /> <br /> MadWagnerhttps://www.blogger.com/profile/01829209684898478688noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-77175786772122381592014-07-28T23:39:06.396+01:002014-07-28T23:39:06.396+01:00I built this, but am getting no sound. Just a high...I built this, but am getting no sound. Just a high pitch whine noise. I'm gonna get out the audio probe. Hopefully I can debugg this bugger.MadWagnerhttps://www.blogger.com/profile/01829209684898478688noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-71202293884874734762014-04-26T20:48:04.065+01:002014-04-26T20:48:04.065+01:00Damn it sounds good.Damn it sounds good.Soporifixhttps://www.blogger.com/profile/11285224042368983404noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-43851663959365374212014-04-25T13:43:58.188+01:002014-04-25T13:43:58.188+01:00Thanks!Thanks!Soporifixhttps://www.blogger.com/profile/11285224042368983404noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-37983558079067074512014-04-25T10:18:53.793+01:002014-04-25T10:18:53.793+01:00Yes that's exactly what you need to do, wire f...Yes that's exactly what you need to do, wire from board to Treble 1, daisy chained out to Bass 1IvIarkhttps://www.blogger.com/profile/08416945174853142251noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-14153864875155011512014-04-25T07:45:41.183+01:002014-04-25T07:45:41.183+01:00Maybe a silly question - "treble 1 to bass 1&...Maybe a silly question - "treble 1 to bass 1" means the treble 1 wire soldered to treble 1 lug then jumpered to bass 1 (or 3)? Or treble 1 wire directly to bass 1?Soporifixhttps://www.blogger.com/profile/11285224042368983404noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-88840261950479260222014-03-02T13:53:48.646+00:002014-03-02T13:53:48.646+00:00Hi John, your Galilieo looks very nice!
I built t...Hi John, your Galilieo looks very nice!<br /><br />I built the CB 30 and i have the same problems with low volume and gain and a dull sound.<br />How did you solve this?<br /><br />The drain at Q2, Q4, Q5 is 9 volts. is that ok? in the Schematic it looks like they are directly connected to the 9 volt supply<br /><br />The drain of Q1 & Q3 is 4.77 & 4.43<br /><br />Are the voltages ok?Njokkihttps://www.blogger.com/profile/12608325505627647877noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-68421898453710770572013-10-23T13:05:49.514+01:002013-10-23T13:05:49.514+01:00Q1, Q2 and Q3 ,Q4 are in a muamp configuration and...Q1, Q2 and Q3 ,Q4 are in a muamp configuration and shouldn't be as susceptible to biasing problems, although you could always swap the source resistors of Q1 and Q3 to trimmers if you wanted some tweakability. Q5 may need biasing though and so again you may want to swap the source resistor for a trimmer. Personally I'd just socket the JFETs and build it as is and maybe swap a few about and see how it affects the soundIvIarkhttps://www.blogger.com/profile/08416945174853142251noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-29348267856340872932013-10-23T03:28:06.605+01:002013-10-23T03:28:06.605+01:00any info on biasing the jfets with this circuit? ...any info on biasing the jfets with this circuit? or is it one of those ones that doesnt need to be? i have enough 2n5457's that I could match them and just find one resistor value to use for each stageGoldenmonkeycolorhttps://www.blogger.com/profile/15980829818332614750noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-8811436113228945332013-06-10T20:39:38.587+01:002013-06-10T20:39:38.587+01:00they stay on, I don't overcoat them.they stay on, I don't overcoat them.johnkhttps://www.blogger.com/profile/00643996045674470081noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-39490755777762281952013-06-10T20:37:51.398+01:002013-06-10T20:37:51.398+01:00One more thing, do you spray over those or do they...One more thing, do you spray over those or do they just stay on?Jarrett Trezzohttps://www.blogger.com/profile/01510785395468117915noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-38273264312353552852013-06-10T20:33:55.421+01:002013-06-10T20:33:55.421+01:00I'm sold... going to order one of these now!I'm sold... going to order one of these now!Jarrett Trezzohttps://www.blogger.com/profile/01510785395468117915noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-36829736135197791402013-06-10T18:40:32.784+01:002013-06-10T18:40:32.784+01:00a PT-2100 with white on clear 3/4" tape.a PT-2100 with white on clear 3/4" tape.johnkhttps://www.blogger.com/profile/00643996045674470081noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-89099397106260675442013-06-10T18:19:21.607+01:002013-06-10T18:19:21.607+01:00...and which tape did you use? A standard laminate......and which tape did you use? A standard laminated white on clear tape?Rockenhttps://www.blogger.com/profile/16186604987883793974noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-54673082950271543122013-06-10T17:56:56.406+01:002013-06-10T17:56:56.406+01:00Cool !
There are many,which model did you used ?Cool !<br />There are many,which model did you used ?Tsaddeoushttps://www.blogger.com/profile/18087936952365005561noreply@blogger.com