fleabag Posted January 29 Share Posted January 29 This is weird. When i switch on my amp, and use blend knob to select neck pup or bridge, the bridge pup is fine, but when moving to neck pup, i get about 1 second of full volume, then it disappears, to the point where its barely audible in comparison to the bridge pup. This is not a pickup height problem, as its far too dramatic a change. Nor is it an 18v battery problem. I've fitted 2 different sets of fully charged 9v's x2 First thoughts were a dodgy wire on the blend pot, but this has proved not to be the case. Could this be a preamp problem ? If it is, i cant fix this. Too complicated Quote Link to comment Share on other sites More sharing options...
PaulThePlug Posted January 29 Share Posted January 29 What Ibby?.. Think i've got Pups n 3 pot Pre out an SR400, Maybe A 2 Pot Stacked out of an older SR300... Any Board Numbers, maybe try a board to check? Quote Link to comment Share on other sites More sharing options...
fleabag Posted January 29 Author Share Posted January 29 (edited) Its a BTB770PB 5 pot, 3 band Pre. VOL BLEND BASS MID TREB .. its wiring chaos in there 😀 Edited January 29 by fleabag Quote Link to comment Share on other sites More sharing options...
fleabag Posted January 29 Author Share Posted January 29 (edited) Its possible that the blend pot is going AWOL, or maybe i need to pull the Neck Pup and check that pickup wiring, as the next thing to do. By the way, the preamp is a Bart MK-2B 18v according to the stamp on the pcb Edited January 29 by fleabag Quote Link to comment Share on other sites More sharing options...
tauzero Posted February 15 Share Posted February 15 The preamp may well be dodgy. I'm pretty sure that Bart preamp will be similar to a Bart preamp that was once fitted to my Sei - the pickups are wired direct to buffers in the preamp, then the two buffer outputs go to the blend control. It sounds as if something funny is happening involving a capacitor in the neck buffer, though I can't be more specific than that. The solution for mine was replacing the preamp (with a Delano Sonar). 1 Quote Link to comment Share on other sites More sharing options...
fleabag Posted February 16 Author Share Posted February 16 Unfortunately, my talent for lectronics ends at soldering up a V V T , J type , almost as simple as a P bass. I dont know what a buffer looks like or where it is in that mess of spaghetti Quote Link to comment Share on other sites More sharing options...
tauzero Posted February 16 Share Posted February 16 You could see if you could get a direct replacement off Reverb - at least it's plug-and-play. The vast amount of spaghetti is because of the buffers - they prevent the pickups interacting with the volume and blend controls. The average preamp has the pickups going into the blend and volume controls, then to the preamp, tone controls wired to that, then out to the jack. These Barts with onboard buffers have the pickups going into the preamp, then back out to the blend and volume, then back in to the preamp with the tone controls, and finally out to the jack. 1 Quote Link to comment Share on other sites More sharing options...
fleabag Posted February 16 Author Share Posted February 16 Very odd, but the volume came back, disappeared for a bit then came back again. How i love intermittant faults Quote Link to comment Share on other sites More sharing options...
Marco.EB Posted February 17 Share Posted February 17 I love Ibanez, I love BTB, I hate those fake Bart's. lol. No offense if you like 'em , that's the most important part. Intermittant faults are mostly due to a grounding issue or a bad soldering. You have to check every wire and if it's not broken and correctly welded. Best option is to play and touch every component, wire, pickup to find the location of the issue. BTW in worst case I have a set of BH2 pickups in stock, barely used, if you want them I can "sell" them to you for pennies. (coming from a EHB1000) Hope it can help. 1 Quote Link to comment Share on other sites More sharing options...
fleabag Posted February 17 Author Share Posted February 17 Yeah no offence and yes i do like the pickups. Tone is very subjective as we know. Im pretty sure its not the pickup. As you say, probably a solder joint, but havent found it yet. I'll keep at it Quote Link to comment Share on other sites More sharing options...
fleabag Posted February 17 Author Share Posted February 17 (edited) Finally - found the bluddy culprit !! The middle white block of the 3 in the preamp , below , was the perpetrator, and nothing to do with faulty blend pot or faulty pickups. I had the bass on the floor, vol up, and dialling the blend between pickups, whilst probing the various terminations. Found that middle white block had some dodgy crackles, and tapping it cut the volume and tapping again brought volume back. Pulled control cover off, fired up the solder station, ripped off the sticky back insulator, and heated all the solder joints up till i see the solder flow. Job done - everything is as it should be. @tauzero Think you called it. Dodgy preamp, but only a slightly failing solder joint rather than failing preamp. Which is what @Marco.EB advised. So you were both on the money. Which joint, dont know, cos i heated them all up, but carpet bombing all joints has sorted it Edited February 17 by fleabag 4 1 Quote Link to comment Share on other sites More sharing options...
tauzero Posted February 17 Share Posted February 17 10 hours ago, Marco.EB said: I love Ibanez, I love BTB, I hate those fake Bart's. They're MK2, not BH2. I think it's just the BH2 that are the "fake Barts". Quote Link to comment Share on other sites More sharing options...
tauzero Posted February 17 Share Posted February 17 Glad you got it fixed. Dodgy joints are a right sod (and a problem as you get older too). 1 Quote Link to comment Share on other sites More sharing options...
Marco.EB Posted February 18 Share Posted February 18 On 17/02/2024 at 23:35, tauzero said: They're MK2, not BH2. I think it's just the BH2 that are the "fake Barts". MK1 , MK2 and BH2 are "fake Barts", produced by Ibanez. So as Doug from Bartolini told me. They're not produced in USA and just co-designed with Bartolini. As long as the tone is on the spot for the player it doesn't matter anyway. I don't like BH2 but I like MK1. I like high end pickups as much as the cheap DX5 on my old '99 Ibanez. No judgement here, just to share infos I got from Bartolini directly (I'm in contact with them to get Bart's for my future projects). On 17/02/2024 at 23:26, fleabag said: Finally - found the bluddy culprit !! The middle white block of the 3 in the preamp , below , was the perpetrator, and nothing to do with faulty blend pot or faulty pickups. I had the bass on the floor, vol up, and dialling the blend between pickups, whilst probing the various terminations. Found that middle white block had some dodgy crackles, and tapping it cut the volume and tapping again brought volume back. Pulled control cover off, fired up the solder station, ripped off the sticky back insulator, and heated all the solder joints up till i see the solder flow. Job done - everything is as it should be. @tauzero Think you called it. Dodgy preamp, but only a slightly failing solder joint rather than failing preamp. Which is what @Marco.EB advised. So you were both on the money. Which joint, dont know, cos i heated them all up, but carpet bombing all joints has sorted it Cool you've found the issue and fixed it. 2 Quote Link to comment Share on other sites More sharing options...
PaulThePlug Posted February 19 Share Posted February 19 1 hour ago, Marco.EB said: ...I like MK1... Same here / hear... In my SR600. Reverse P in a Soapbar, not a Full Width Humbucker as often asumed and compared with. 2 Quote Link to comment Share on other sites More sharing options...
LeftyJ Posted February 19 Share Posted February 19 8 hours ago, Marco.EB said: MK1 , MK2 and BH2 are "fake Barts", produced by Ibanez Cort. FTFY. When they were first released, they were in the Cort Artisan series (A4/5/6 and B4/5/6). Cort produces them in-house and it wasn't until years later when Ibanez first used them in some of their Cort-built models. Cort is also behind the Hipshot-licensed hardware and Select by EMG pickups, which can be found in many Korean-made Hohners and used to be in the Spirit by Steinberger guitars and basses and several Cort basses in the 1990s 2 Quote Link to comment Share on other sites More sharing options...
fleabag Posted February 24 Author Share Posted February 24 After all that faffing around, it seems the preamp has changed it's mind and now no volume at all from either pickup. Just massive crackles and static noise when touching the preamp in certain areas. By the time i've paid someone to sort this out, i may as well replace it. The Mk2B preamp on it's own ( no pots etc ) is too hard to find, so it looks like i have to replace the whole lot with a 3 band 5 knob preamp. No mini toggle. Apart from East UK units, is there anything else i could look for ? Quote Link to comment Share on other sites More sharing options...
Marco.EB Posted February 24 Share Posted February 24 Bartolini. Fits perfectly Ibanez and sounds dope. HR5.2-AP/918 Quote Link to comment Share on other sites More sharing options...
fleabag Posted February 25 Author Share Posted February 25 Difficult to find here Quote Link to comment Share on other sites More sharing options...
PaulThePlug Posted February 25 Share Posted February 25 On 29/01/2024 at 22:05, PaulThePlug said: What Ibby?.. Think i've got Pups n 3 pot Pre out an SR400, Maybe A 2 Pot Stacked out of an older SR300... Any Board Numbers, maybe try a board to check? Your Pups OK? I'll have another look, see what Pups 'n Pre i've got from the 300 and 400... £DunnoButReasonable? 1 Quote Link to comment Share on other sites More sharing options...
fleabag Posted February 25 Author Share Posted February 25 Thanks Paul, but yeah the pickups are ok. Its definately the preamp. Jusy touching it makes crackle like and old witch Quote Link to comment Share on other sites More sharing options...
Marco.EB Posted February 25 Share Posted February 25 (edited) Pff I got an Ibanez pre, but the wires are cutted... if tou want to solder them back, I can send it to you for free ... Otherwise I have a Uni-Pre 5 on my Nitti and it's awesome. Edit : or I have a Warwick 4 knob pre but you will have to put a dummy knob. Edited February 25 by Marco.EB 2 Quote Link to comment Share on other sites More sharing options...
fleabag Posted February 25 Author Share Posted February 25 👍 Thanks Marco - if i cant find an original MK 2B, i think the EAST uni-pre 5 is what i'll go for Quote Link to comment Share on other sites More sharing options...
Marco.EB Posted February 25 Share Posted February 25 3 hours ago, fleabag said: 👍 Thanks Marco - if i cant find an original MK 2B, i think the EAST uni-pre 5 is what i'll go for John is really a nice guy.... costed me a lot in Belgium because of VAT and import fees but worth the 400... it's the most versatile pre I ever tried, transparent although, a bit too many options but it's inside that is interesting.. caps can be swapped, frequencies can be adjusted, each pickup gain too... careful, it takes a lot of place... I recommand you check if your compartiment can embed it if it's the same as my Nitti: https://youtu.be/rGdyNtqf9G8?si=uPU2rFYvJNVO6VQN 1 Quote Link to comment Share on other sites More sharing options...
fleabag Posted February 25 Author Share Posted February 25 Thanks Marco. Yes his preamps are spectacular I've been a personal friend of John since the early 1990's, jammed with him, been to his house on several occasions, and owned a few different East preamps, so i'm quite famiiar with him and his electronics. If i decide on the UNI-PRE 5, i will go to John's home, and take my bass, just to be sure. I dont speak your language mate, so the YouTube video is not possible to watch 1 Quote Link to comment Share on other sites More sharing options...
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