View Full Version : Boss TR-2 mod
konasexone
02-27-2008, 07:44 PM
Does anyone have specifics (component values, replacements, etc.) with regards to modifying the Boss TR-2 tremolo pedal to something more conventionally palatable, assuming one isn't completely satisfied with the straight from the factory status quo. I don't have one particular mod in mind.
mhammer
02-27-2008, 09:39 PM
Not an unreasonable request. Just not a strong basis for suggesting something concrete. Gotta be a little more specific, buddy. What does "conventional" mean to you?
iaresee
02-27-2008, 09:47 PM
Cutting the C4 capacitor (literally removing the path by clipping one lead, not jumpering it) is a popular mod on the older TR-2's -- it's hit and miss on whether it has an effect. I've heard yes and no.
You can replace R9 with a trimpot (Keeley uses a concentric pot on his mod) to adjust the volume boost. Lowering R9's resistance value increases volume so go for a 10k trimpot and you can go from stock volume to boosted volume.
Heres a schematic: http://www.schematicheaven.com/effects/boss_tr2_tremolo.pdf
mhammer
02-28-2008, 07:57 AM
Or if you want the less conventional, replace both C20 and C21 with a .1-.22uf cap. That will get you modulation rates that move into the audio range for "rubber band" ring-modulation-like effects. Not quite the mayhem of the EHX Frequency Analyser, but well into that direction.
konasexone
02-28-2008, 11:56 AM
Not an unreasonable request. Just not a strong basis for suggesting something concrete. Gotta be a little more specific, buddy. What does "conventional" mean to you?
Ok. I got a schematic of the thing and i'm looking it over today. I'm going to take these recommendations into consideration and see what they would do. I'll model them in multisim. I might try a few of my own to see. I just picked the pedal up and I don't mind it. Do you fellows know what the major beefs about it are?
Teleplucker
02-28-2008, 01:06 PM
I just picked the pedal up and I don't mind it. Do you fellows know what the major beefs about it are?
There seems to be 2-3 versions of the pedal.
The two major beefs are: apparent volume drop when engaging the pedal and and lots of background noise. These seemed particularly noticeable on early units.
On the one I have (which I got from a fellow forum member and have not paid....heehee...I will, promise!), it had noise and volume drop. I tried removing C4 and it didn't really do anything. I tried a few resistors in R9. I stayed with 5K6, although it's still a little too loud, engaged (may try 6K2 down the road). I also put 2 - .001uF caps in parallel with C14 and C19. And, based on the wisdom of Mr. mhammer, changed C7 to 680pF and R12 to 27K. The last change also boosts volume in a different way than the R9 changes.
The net net is it now sounds good and strong. There is still background noise (combination of hearing the "beating" of the volume throbs and typical increased noise from upping the gain/volume boost), however, it's fine on a gig in a noisy bar. I wouldn't record with it, but I have a hand-wired/true bypass unit for that or my 68 Princeton which has the bias vary trem circuit in it and sounds better than any pedal, anyhoo. My purpose with the TR-2 was to have an inexpensive, Boss-based pedal option for gigs where the stage was small, clientele shifty, and/or load-in a PITA.
IMO...YMMV etc. etc.
mhammer
02-28-2008, 01:55 PM
I realize the thread is about the TR-2 in particular, but I will put in a little plug for the Line 6 Tap Tremolo, given the passing mention of the bliss of bias-tremolo. The Tap Tremolo has a bias-trem emulation setting, and its real nice. How well it nails the real thing is not for me to say, but it's a joy to play.
konasexone
02-28-2008, 03:13 PM
I agree Line 6 make a good effect unit sound wise, but I just can't rely on them.
I have a DL4 that is soo.. flaky and I've had an AX212 fry on me. Line 6 had to swap out the whole main board. Its no surprise they've introduced a valve/hybrid pre-amp amplifier.
mhammer
02-28-2008, 04:02 PM
A good product, and a good product with every one that rolls off the line, can be two separate things. I was fortunate enough to be involved in the beta-testing of the Tone Core series and was sent a box with just about every one of the pedals as a thank you. One of the modules (the verbzilla module) didn't work and one of the docks needed repair. Remember those little metal ladybug things with a little piece of spring steel you would press to make a clicking noise, just to drive your parents crazy? Not now, doofus, when you were little. Line 6 used a similar piece of concave spring steel to place some resistance under the footswitch in the Tone Core pedals. That way, they could have one very soft-touch switch for tap tempo, and a second harder-touch switch under the same foot treadle, saving space with a dual-function foot-motion. Well, one of the pedals I got accidentally had two of those concave metal pieces sandwiched together. Very hard to see, and undoubtedly one of the pedals that came off the line between random quality-control checks. Because I got mine for free, I didn't mind yanking it apart to see what the problem was, and repaired it easily. Iimagine anyone who spent $120 on theirs would have been less forgiving.
Again, a good pedal, but not necessarily one that would be assembled absolutely flawlessly every time. I suppose that is one of the things you get when you buy boutique; somebody had to physically build the unit and try it out before sticking it in the packaging to ship out. The build quality is probably the same, but the quality control is more difficult to maintain when you shift to high-volume production.
iaresee
02-28-2008, 04:13 PM
I agree Line 6 make a good effect unit sound wise, but I just can't rely on them.
The ToneCore packaging and the 4-series packaging are not the same. The ToneCore units most definitely fall into the "tank" category. Heavy mofo's in nice diecast packaging.
vBulletin® v3.7.3, Copyright ©2000-2008, Jelsoft Enterprises Ltd.