tag:blogger.com,1999:blog-6847048658257278783.post5874498483968407557..comments2024-03-19T08:04:50.887+00:00Comments on Guitar FX Layouts: Emerson Custom Guitars Em-DriveIvIarkhttp://www.blogger.com/profile/08416945174853142251noreply@blogger.comBlogger208125tag:blogger.com,1999:blog-6847048658257278783.post-43273521739228416172019-06-13T10:33:57.284+01:002019-06-13T10:33:57.284+01:00Also I've wired all of mine point to point bec...Also I've wired all of mine point to point because the component count is so small. My friend has all 3 I've built though (the ones that stayed built anyway) because I don't particularly like this OD, I much prefer what I can get put of my amp's preamp.Asmithhttps://www.blogger.com/profile/08784218011464346481noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-7463154961451841702019-06-13T10:23:40.593+01:002019-06-13T10:23:40.593+01:00I've built a few of these over the past couple...I've built a few of these over the past couple of years because a friend got one and liked it. I knew of the circuit and its simplicity so I said I could probably build one out of spare parts. I ran into the buzzy farty problems like many on here and the collector voltage was way to close to either 0 or 9V can't remember (I use the MPSA18 like the originals I think). I use a 10k multi turn trim pot in place of the 4k7 and adjust that to get around half the supply voltage works every time and sounds like the real thing. That's my advice and experience with this layout.<br /><br />Now it's my turn to ask a question.<br /><br />Yesterday I got my first chance to look in the back of a real one. The components are all hidden under the PCB when mounted and I didn't remove the circuit because it's pot mounted and would be quite intrusive since the pedal was not mine and I didn't have a lot of time spend probing voltages either. But there is an always on LED inside the enclosure not the indicator. I wish I could have had a look at the top of the board to trace the pcb and read all the component values for myself. So my question is does anyone know what it's doing in there? I'm doubting the validity of the the schematic this layout is based on.<br /><br />I'm trying to think of any reason why it might be in there (in parallel with the actual effect so that it has no effect essentially). <br /><br />BTW the collector voltage in this real one is 4.3V powered on a EHX power supply measuring at 9.75V. The ones I've built are all adjusted to 4.9V on the same power supply and sound good and don't see the need to change the past ones but for anyone who wants to build one with this method it gives a value to aim for.Asmithhttps://www.blogger.com/profile/08784218011464346481noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-25414888396078660102018-08-28T16:31:59.361+01:002018-08-28T16:31:59.361+01:00Anyone got any suggestions for the offboard wiring...Anyone got any suggestions for the offboard wiring part of this pedal? I've seen different offboard diagrams for different onboards of this pedal but I'm very new to making pedals so im not sure how to wire this board up to the lins, logs and 3PDT, battery etc. I've read the documents for all the parts and cant quite piece it all together so any help would be appreciated. thanks.Anonymoushttps://www.blogger.com/profile/14867545691351163477noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-2272419806305254792018-06-26T15:34:46.722+01:002018-06-26T15:34:46.722+01:00My pedal got with very loud pop ....so I put a pul...My pedal got with very loud pop ....so I put a pulldown resistor 2.2M from out to ground and it worked very well.Dr.Blueshttps://www.blogger.com/profile/02704870861123746983noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-32814399389027296952017-12-11T03:08:06.932+00:002017-12-11T03:08:06.932+00:00I appreciate the tip for an 2.2k resistor to repla...I appreciate the tip for an 2.2k resistor to replace the 4.7k. It worked great and after that with the 2n5088 it sou dad like the pedal was transparent like everyone talked about. When I had the 4.7k resistor in circuit I used an 2n4401 transistor and there was more bass and gain to the sound. I am going to try an mpsa18 next since I rocketed the transistor. I'll make a video to shoe the differences. <br /><br />I did wonder if there was a way to put different transistors on a switch to allow "options" for people to choose from for the circuit. David Wilsonhttps://www.blogger.com/profile/04433553745139287511noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-53398813053128615942017-12-11T03:02:37.687+00:002017-12-11T03:02:37.687+00:00This comment has been removed by the author.David Wilsonhttps://www.blogger.com/profile/04433553745139287511noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-29179384271134492792017-12-07T23:44:42.898+00:002017-12-07T23:44:42.898+00:00Hi guys,
I had same issues with the fuzzy, low out...Hi guys,<br />I had same issues with the fuzzy, low output ugly distortion as everybody else and the solution was to simply replace the 4,7K resistor with a 2,2K. No need to replace the 2n5088 transistor.<br />As Mirosol said, it's a thing of bias. At first I tried doubling the resistance by putting two 4,7K resistors in a row but the problem got worse. Which was a signal for me to do the opposite - and it worked..<br />Since I am a slav, I used old 100N PIO tesla caps. These Teslas gave more clarity than regular FOIL caps. It could have been just this specific case though..<br /><br />Thanks for the layout!Anonymoushttps://www.blogger.com/profile/11333318288938501673noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-16147497776446696452017-11-21T15:21:28.857+00:002017-11-21T15:21:28.857+00:00Just finished this one. Sounds amazing with my cor...Just finished this one. Sounds amazing with my cornish buffer in front of it. I replaced the 5088 with a BC549. Spin it 180! The 5088 sounded a little fuzzy/farty especially with the volume cranked. After the switch I'm really digging this thing.Anonymoushttps://www.blogger.com/profile/11975532526699795523noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-87151715030986497032017-10-02T08:20:24.727+01:002017-10-02T08:20:24.727+01:00I still don't understand how you mean it. So r...I still don't understand how you mean it. So replace the 4k7 with 1k? But where is an upped lead? Hope you can explain to me.<br /><br />And you are very certain that the light hiss sound that disappears after a few milliseconds is a bias issue and not a broken component?servusjonhttps://www.blogger.com/profile/01242400278141198962noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-64409901796542207802017-09-27T00:06:35.586+01:002017-09-27T00:06:35.586+01:00You don't need PIO capacitors. any capacitor w...You don't need PIO capacitors. any capacitor will doFunkManhttps://www.blogger.com/profile/18207143981540857135noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-34912239474634683392017-09-19T07:24:47.131+01:002017-09-19T07:24:47.131+01:00I tried it yesterday with a 50k poti instead of th...I tried it yesterday with a 50k poti instead of the 4.7k resistor and found a good spot. But I still had a very light grain/hiss/fuzz sound that was more audible on lower strings and disappeared after a few milliseconds. <br /><br />Would you get a poti with 10k to tweak it a bit more? I played a lot on that 50k poti but that behaviour couldn't be removed :-(<br /><br />Don't quite understand what IvM and mirosol want me to do. Will this solve my problem?<br /><br />But I can tell you that moment I first had some more decent sounds out of that circuit was very satisfying after fiddling around for 8 hours trying to fix itβ¦servusjonhttps://www.blogger.com/profile/01242400278141198962noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-45889493889400180672017-09-19T07:23:01.111+01:002017-09-19T07:23:01.111+01:00This comment has been removed by the author.Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-5112833552455581922017-09-19T06:40:43.943+01:002017-09-19T06:40:43.943+01:00Hmmm.. Nope. You'll need to leave the upped le...Hmmm.. Nope. You'll need to leave the upped lead of the 1K out of the board and take the pot's lug 3 to that hanging lead. Lug 2 to +V strip. That's the way to do it. That's what i thin lvM was trying to say..<br /><br /><br />Your bias is still off with that behaviour.<br />+mmirosolhttps://www.blogger.com/profile/02400327798106357876noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-40085013621842519782017-09-19T01:12:16.937+01:002017-09-19T01:12:16.937+01:00Replace the 4k7 res for 1k.
Then, +9v to lug 2 (50...Replace the 4k7 res for 1k.<br />Then, +9v to lug 2 (50k pot), and lug 1 to board v in.<br /><br />That way, it can be used as some kind of "gain" knob too: more 50k's... more gain.<br />IvMhttps://www.blogger.com/profile/02555112437631034123noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-81669849510716514462017-09-18T21:33:42.952+01:002017-09-18T21:33:42.952+01:00Got it wo work.
But there is still a bit of fuzz s...Got it wo work.<br />But there is still a bit of fuzz sound that disappears a few milliseconds after the attack. What can be wrong here?<br />Broken transistor? How can fix this?servusjonhttps://www.blogger.com/profile/01242400278141198962noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-78766587774333782082017-09-18T06:21:34.991+01:002017-09-18T06:21:34.991+01:00Hey Trev, most people just use whatever is at hand...Hey Trev, most people just use whatever is at hand - don't buy into the 'mojo' stuff that companies use to sell their stuff. Tayda is probably the cheapest place you can get components and has pretty much everything you could want at very good prices. That said, having cool looking components is fun, just keep in mind that the 'sound' they may impart is probably mainly psychological!Anonymoushttps://www.blogger.com/profile/06201678011261105677noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-66489468986351095322017-09-18T05:17:33.726+01:002017-09-18T05:17:33.726+01:00Where did you put the poti? And where the 1k resis...Where did you put the poti? And where the 1k resistor?<br />You can write me down the coordinates of the vero of each component. I am total noob πservusjonhttps://www.blogger.com/profile/01242400278141198962noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-88209294825189075872017-09-18T01:36:41.082+01:002017-09-18T01:36:41.082+01:00Marisol is right: if you don't bias correctly,...Marisol is right: if you don't bias correctly, it sounds totally like shit...<br />I used a A50K pot with 1k resistor in series, and use it as "gain" knob.IvMhttps://www.blogger.com/profile/02555112437631034123noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-64797365670808206452017-09-17T12:50:14.677+01:002017-09-17T12:50:14.677+01:00Hey guys, planning on building this as well as a c...Hey guys, planning on building this as well as a cornish buffer as my first build! Had trouble finding a single source website to fulfill all my specific needs, is this normal? I used a combination of mojotone and small bear. Also does it matter the specific kind of 100n caps i use? Would someone kindly link me to what they would use as a reference? Much appreciated! Anonymoushttps://www.blogger.com/profile/12685635256875481652noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-40303926199879614122017-09-16T18:48:16.183+01:002017-09-16T18:48:16.183+01:00This here may be the worst single circuit in terms...This here may be the worst single circuit in terms of bias. Many JFET-based circuits are also a pain to get running properly. With all opamp based circuits, they need to be biased correctly by design, otherwise they won't work at all. So no worries with those. (In case you are wondering - simplified, the bias means the relationship of voltage at the input and the output of the device. These two voltages need to be correct for a transistor, regardless of type, for it to function properly.)<br /><br />I suggested the pot in case you had some lying around. However. If you want it running with relative ease, then try taking a 470k resistor from supply to transistor base and 47k resistor from base to ground. It won't sound exactly the same, but it'll work for sure.<br />+mmirosolhttps://www.blogger.com/profile/02400327798106357876noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-80962487594990758742017-09-15T22:25:11.085+01:002017-09-15T22:25:11.085+01:00Will this work? https://www.musikding.de/Alpha-Pot...Will this work? https://www.musikding.de/Alpha-Potentiometer-16mm-50k-lin<br />One which pins do I connect the wires?<br /><br />Is biasing an issue that happens with other tagboards such as the timmy or this one? http://tagboardeffects.blogspot.de/2014/02/emerson-custom-guitars-paramount.html<br /><br />servusjonhttps://www.blogger.com/profile/01242400278141198962noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-21150899177002356912017-09-15T22:04:27.752+01:002017-09-15T22:04:27.752+01:00Using something like 10-50K linear pot wired to re...Using something like 10-50K linear pot wired to replave that resistor could also work. However, i'm quite certain it is a bias issue. Can't be anything else with that part count.<br />+mmirosolhttps://www.blogger.com/profile/02400327798106357876noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-27779423641105864012017-09-15T21:35:29.080+01:002017-09-15T21:35:29.080+01:00Thanks for the quick reply. I sadly don't have...Thanks for the quick reply. I sadly don't have a trimmer but I tried with different resistors in that range. No noticeable change :-(<br /><br />Is that so hard with every tagboard or is the em drive so difficult in particular? Building was very quick but I spent almost 8 hours on trying out different things.<br /><br />servusjonhttps://www.blogger.com/profile/01242400278141198962noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-5441198725809006262017-09-15T07:32:52.982+01:002017-09-15T07:32:52.982+01:00The 4k7 won't bias your transistor correctly. ...The 4k7 won't bias your transistor correctly. There are numerous reasons for that. Main one being that your transistors are not from the same exact batch that Emerson has. Now. To make it usable for your transistors, desolder the 4k7 and take a 20k trimpot's lugs 1 and 2 to the holes where the resistor was. Then play your guitar and turn the trimpot until the circuit sounds decent enough. Then measure the exact resitance of that trimpot and reinstall a resistor that is exactly the value of the trimpot. Or just leave the trimpot in place.<br /><br />Even easier would be to just solder in something like 10k resistor in place of that 4k7 and hope it'll work right.<br />+mmirosolhttps://www.blogger.com/profile/02400327798106357876noreply@blogger.comtag:blogger.com,1999:blog-6847048658257278783.post-36586102768810985142017-09-15T03:00:25.754+01:002017-09-15T03:00:25.754+01:00Built the compact non mojo version with a 2N5088 a...Built the compact non mojo version with a 2N5088 and it sounded noise gaty farty fuzzy. Tried it MPSA13 β no change. All soldering is ok. Used MKT-01uF (https://www.musikding.de/MKT-01uF) for my capacitors. <br />Did two nights of debugging but still getting farty broken sound :-(<br /><br />Anyone please give me a hint? servusjonhttps://www.blogger.com/profile/01242400278141198962noreply@blogger.com