tag:blogger.com,1999:blog-6847048658257278783.post2671489025625372542..comments2024-03-13T04:13:52.242+00:00Comments on Guitar FX Layouts: Sadowsky PreampIvIarkhttp://www.blogger.com/profile/08416945174853142251noreply@blogger.comBlogger172125tag:blogger.com,1999:blog-6847048658257278783.post-45823760944590132042023-07-19T20:16:33.031+01:002023-07-19T20:16:33.031+01:00This a great preamp, I built the pedal version. co...This a great preamp, I built the pedal version. couldn't get the 2N5457s to work, way to much distortion and noise.<br /><br />replaced with 2 x J201 JFET SMT on Adaptor Board V2 (QD283) from bitsbox<br />and added an A100k 6mm input trim to set exact pre volule level.<br /><br />Thanks to the op and all the guys who helped with mods in the thread.<br /><br />peace<br />Matt H ;-)Matt Hooperhttps://www.blogger.com/profile/12502905110046284644noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-32408370305683581522022-09-16T16:34:15.473+01:002022-09-16T16:34:15.473+01:00I had huge problems using a J201 for this. Turns o...I had huge problems using a J201 for this. Turns out most of them are fake chinese ones and I never got to bias them correctly on the drain (stayed around Vcc the whole time). Substituted the fake J201 with a J113 and changed the drain bias resistor to 8.2k which sets the bias voltage to about 4.5-5V and reduces noise significantly for my setup.<br /><br />My J113 version works good now, I might build a active jazz bass curcuit around this cause it really gives you a lot of different soundsLeonhttps://www.blogger.com/profile/18103150275766073627noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-11734025711386772622022-08-26T15:04:38.511+01:002022-08-26T15:04:38.511+01:00Just built Johnk's version with the 330k pulld...Just built Johnk's version with the 330k pulldown resistor (http://johnkvintageguitars.homestead.com/Effects/others/Sadowsky/0001-SadowskyBassPreamp.png). <br /><br />When I used the 2N5457 there was quite a lot of gain and distortion even before noon on the bass knob. Used 2 J201s and things changed drastically. Probably my favourite DIY bass preamp to date!Donchovhttps://www.blogger.com/profile/15275717417873168304noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-35473090886663942512021-12-11T13:52:57.215+00:002021-12-11T13:52:57.215+00:00just a minor addition:
I'm going to build this...just a minor addition:<br />I'm going to build this one (1 comment below the other johnk) <br /><br />http://johnkvintageguitars.homestead.com/Effects/others/Sadowsky/0001-SadowskyBassPreamp.png<br /><br />this is narrower by 1 column...<br />but this is NOT the reason...<br />this version is the pedal version, that's why I'm building this...<br />"pedal version" here means: the anti-pop pull down resistor, <br />which is only necessary when using a power supply, not a battery... so, I need this :) <br /><br />but for you, both versions are equally cool (in my moderately experienced opinion)j-peehttps://www.blogger.com/profile/06075769174607916244noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-67259555768577233952021-12-11T13:44:26.426+00:002021-12-11T13:44:26.426+00:00I suggest JohnK's version:
(mentioned among th...I suggest JohnK's version:<br />(mentioned among the comments: johnk25 January 2014 at 01:43)<br /><br />http://johnkvintageguitars.homestead.com/Effects/others/Sadowsky/SadowskyBassPreamp.png<br /><br />I am going to build this version, too, that's why I'm suggesting it...j-peehttps://www.blogger.com/profile/06075769174607916244noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-60783268665736098692021-12-06T05:44:56.492+00:002021-12-06T05:44:56.492+00:00This comment has been removed by the author.Juan 21https://www.blogger.com/profile/10028339623679539413noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-18496625367016842472021-12-06T05:44:15.205+00:002021-12-06T05:44:15.205+00:00hi, I read the whole post and I wonder which versi...hi, I read the whole post and I wonder which version can be adapted better to set inside a bass? and what changes do I have to do?Juan 21https://www.blogger.com/profile/10028339623679539413noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-13513231495983286592021-11-25T21:12:24.419+00:002021-11-25T21:12:24.419+00:00This comment has been removed by the author.j-peehttps://www.blogger.com/profile/06075769174607916244noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-88680443168013037112021-11-25T21:00:14.244+00:002021-11-25T21:00:14.244+00:00This comment has been removed by the author.j-peehttps://www.blogger.com/profile/06075769174607916244noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-21246465226053108302021-11-24T22:11:44.894+00:002021-11-24T22:11:44.894+00:00hi,
what do the zeners do?
I'd like to try 9...hi, <br />what do the zeners do? <br />I'd like to try 9.1V zeners, will it be a mistake?<br />j-peehttps://www.blogger.com/profile/06075769174607916244noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-11397285450457749972021-03-22T21:15:19.174+00:002021-03-22T21:15:19.174+00:00it works, I made the JohnK layout, I used 2n7 and ...it works, I made the JohnK layout, I used 2n7 and 330pf, great sound, no noise. thank you JohnK and everyone who makes our diy life happier in these times we live !!!Ricco Seixashttps://www.blogger.com/profile/16351031394073802665noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-91829040477955100802020-12-05T13:27:36.091+00:002020-12-05T13:27:36.091+00:00Bottom of the layout gives the info, the Input fro...Bottom of the layout gives the info, the Input from the stomp switch goes to Volume 2IvIarkhttps://www.blogger.com/profile/08416945174853142251noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-85741925034232466562020-12-05T12:36:40.874+00:002020-12-05T12:36:40.874+00:00Many thanks for this.
Sorry if my question seems s...Many thanks for this.<br />Sorry if my question seems stupid, but where is the input? <br />Thanks.Nemohttps://www.blogger.com/profile/06342502035515706749noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-36818366476942027212020-07-14T19:43:41.337+01:002020-07-14T19:43:41.337+01:00Made johnk's version with 330K pulldown, sound...Made johnk's version with 330K pulldown, sounds amazing! Used SMD MMBF5457 on adapterboards. Subbed the 2,5nF with a 2,2nF that measured 2,3-2,4ish, and the 300p with 270p or 330p.Bolsyohttps://www.blogger.com/profile/14020665811328303796noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-53337702996132443442020-07-01T23:54:26.353+01:002020-07-01T23:54:26.353+01:00This pedal makes a surprisingly good treble booste...This pedal makes a surprisingly good treble booster for guitar. Actually the difference in sound between this and my Dallas range master clone is minimal. Joel Bergströmhttps://www.blogger.com/profile/15100655168227794028noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-52910937051058907852019-09-23T20:26:11.393+01:002019-09-23T20:26:11.393+01:00Hey all, I have completed John’s layout but I am h...Hey all, I have completed John’s layout but I am having a crazy loud pedal with a not so nice sounding distortion. Tried 2n5457’s and J113 transistors. <br /><br />I noticed there are two layouts by John. I build this one: http://johnkvintageguitars.homestead.com/Effects/others/Sadowsky/0001-SadowskyBassPreamp.png<br />But there is another one as mentioned above:<br />http://johnkvintageguitars.homestead.com/Effects/others/Sadowsky/SadowskyBassPreamp.png<br /><br />Is the latter taking care of the volume and distortion problem or is it better to stick with original layout by TBE? Guesthttps://www.blogger.com/profile/06803529551633610340noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-31281047744597051282018-12-12T15:27:56.244+00:002018-12-12T15:27:56.244+00:00btw just had an original at hand and it has 500k f...btw just had an original at hand and it has 500k for volume and 30k for bass and tremble. now i had to use 20k on mine otherwise there was way too much noise, something must be completely different in this layout.<br />Anonymoushttps://www.blogger.com/profile/14185629523083947950noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-26075633829277898912018-09-09T19:33:39.202+01:002018-09-09T19:33:39.202+01:00i have the same exact problem, did you found a sol...i have the same exact problem, did you found a solution?<br />ioannizhttps://www.blogger.com/profile/04689187369968682825noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-26744833748529034832018-07-06T02:38:54.912+01:002018-07-06T02:38:54.912+01:00I had the same issues. Distortion and no headroom....I had the same issues. Distortion and no headroom. The whole thing comes from Q1. Change that one to J201 and the problem will be gone. At least for me this did the trick. Also it is adviced to do power filtering. It can reduce the hiss.Sandorhttps://www.blogger.com/profile/00829542408227432135noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-22276366974747897532017-10-06T15:12:20.881+01:002017-10-06T15:12:20.881+01:00P.o.B pedals
soz read belowP.o.B pedals<br /><br />soz read belowAnonymoushttps://www.blogger.com/profile/14185629523083947950noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-45310026027017950402017-10-06T15:11:53.026+01:002017-10-06T15:11:53.026+01:00P.o.B pedals
You cant have xlr output like this. Y...P.o.B pedals<br />You cant have xlr output like this. You need another board to convert to balanced output. There are a few cheap on the internet or you can build your own ofc.Anonymoushttps://www.blogger.com/profile/14185629523083947950noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-61193479006744036382017-07-03T11:47:06.012+01:002017-07-03T11:47:06.012+01:00The original has xlr outs, any ideas how they wire...The original has xlr outs, any ideas how they wired that? ThanksAnonymoushttps://www.blogger.com/profile/15828893343109077682noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-88452022128591288462017-04-27T12:54:58.525+01:002017-04-27T12:54:58.525+01:00I've installed variable drain resistors to set...I've installed variable drain resistors to set correct bias and decreased both source resistors to 3k9. Also, experimenting with jfets might be worthwile. Mine 2n5457 didn't work properly, j201s seem much better.<br /><br />Now the volume with anticlockwised Treble and Bass is slightly louder than unity.Piotr Kuzemczakhttps://www.blogger.com/profile/07414584324862844805noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-12675456047821301812017-04-23T12:26:30.220+01:002017-04-23T12:26:30.220+01:00Hey nice!!! Could you provide us info on what exac...Hey nice!!! Could you provide us info on what exactly you did to make it work and sound okay?<br /><br />Thanks!Anonymoushttps://www.blogger.com/profile/14185629523083947950noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-3032488479992927452017-04-21T21:00:08.134+01:002017-04-21T21:00:08.134+01:00Finally got it working excellent onboard.
I want ...Finally got it working excellent onboard.<br /><br />I want to make another one for my guitar but have no idea how to modify caps for proper tone freq range. Any advice?...Piotr Kuzemczakhttps://www.blogger.com/profile/07414584324862844805noreply@blogger.com