Page 1 of 1

Amp restoration

PostPosted: Sat Sep 29, 2018 4:05 pm
by Steve Sawyer
I "inherited" this bass amp - a Traynor TS-60B - as a freebie, saving it from being put in the trash. It was apparently owned by a local music store that rents equipment, then sold used and ended up being dragged around a local high school for many years, hence the beautiful "patina".

Despite all the abuse, the poor thing still works, and amazingly, this seems to be a GREAT guitar amp. I've been looking for a simple, bare-bones solid-state guitar amp - nothing more than overdrive and reverb, and have been looking at a $500 amp that fits the bill, then this dropped into my lap. I was amazed at how good my Tele and Strat sounded through this. I can, with the tone controls and EQ get that twangy or even ice-picky tone out of the Tele, or I can tame it right down into a "woman tone".

What I'd like to do is:

a) Build a new cabinet, or at minimum re-cover this cabinet with either tweed or (2nd choice) Tolex. The big advantage with rebuilding is I could build in a removable back-panel, making it an open-back design for using it with a guitar, or left in place when playing a bass through it. I could also explore doing this with the existing cabinet.
b) Make a new faceplate from a sheet of aluminum or stainless. I could add any graphics or lettering (like 1-10 markings around the knobs) using water slide decals which I've done for machinery restorations
c) Replace all the knobs, since one is missing and there's no chance of matching the existing knobs which are in terrible shape. I'd also like to add some fader knobs to the EQ sliders. As you can see the original knobs were big (1 1/2" dia) witches-hat style knobs, and I can't find anything like them anywhere. I'll either have to go with smaller knobs of this type, or as I mentioned above going with simple knobs with just an indicator and print the 1-10 scale (maybe I should go to 11?) on the face plate. I can't find any specs for any of the fader knobs I've found, so I'll just have to buy some and see if I can make them fit the sliders on this.

  • I'd appreciate any thoughts or advice about this project. The existing cabinet is made of reasonably good quality plywood, not particleboard, so no reason to not simply re-cover it. Then again, it wouldn't be out of the question to build a new one from some nice baltic birch ply. I've never done this, but recovering with Tolex seems fairly straightforward. I'd really like to recover it in tweed, but can't (so far) find any tutorials on this online.
  • Also, as to the pot shafts, they measure about 1/4" (.246"/6.26mm on my dial calipers), and appear to be solid, not split, with fine splines. In shopping for knobs, some are identified as sized for 1/4" shafts, some for 6mm, some for 6.4mm. Can I get some advice on selecting knobs that will work with these pots? I was also thinking of turning a set of knobs on the lathe, but it would be nice to have a nice brass insert to match these shafts, but again, my online searching hasn't yet turned up any pot-shaft "bushings" that could do the trick. The shafts of these pots appear to be some kind of plastic, maybe nylon, so they're hard, but don't seem sturdy enough to force a suitably-sized hole in a hardwood knob over them. Alternatively, I see no reason I couldn't cross-drill and tap the wood knobs for set screws, other than they would tend to chew up the shafts a bit when tightened.

Thanks.

Traynor 1.JPG

Re: Amp restoration

PostPosted: Sun Sep 30, 2018 9:53 am
by Brian Evans
I use a solid state bass amp with a Boss RV-2 reverb pedal in front, for my electric work so I know how good they can sound. Doing a cosmetic update on a collectors item is one thing, but this is more of an unknown workhorse, so I would say do what makes you happy. Personally I'd leave it alone, just a good clean and put a knob on the pot that's missing one, but I like things to look like what they are. Electronically I would replace the pair of 2200uF electrolytics that are the main filter caps just after the bridge rectifier, on the basis that they are around 30 years old and deserve a rest. Traynors are known, particularly in Canada, as under-appreciated (back in the day) now highly rated professional quality amps. We had a GuitarMate amp when I was in high school that literally we couldn't give away, it got passed around among the guys and now it's worth over $1K.

Re: Amp restoration

PostPosted: Sun Sep 30, 2018 11:38 am
by Daryl Kosinski
Building a new Cabinet is not that hard. I built myself a franken Fender out of a old Deluxe and Sidekick 65 bass.

Spray on truck bed liner makes a great covering. Here is before and after.

Re: Amp restoration

PostPosted: Sun Sep 30, 2018 11:41 am
by Daryl Kosinski
Here is the after

Re: Amp restoration

PostPosted: Sun Sep 30, 2018 11:45 am
by Daryl Kosinski
When I play Bass I use this Cabinet with a 15 in speaker. I unplug the 12 in the cabinet and plug in the bass cabinet.

Here it is before the spray on covering. The cane grill was some leftover from a chair project turned out cheaper than Fender grill cloth.

Re: Amp restoration

PostPosted: Sun Sep 30, 2018 11:47 am
by Steve Sawyer
Thanks, Brian.

Yeah - I'm still being amazed at how well the highs are coming through on this. Between the tone controls and the EQ, there's a lot of latitude for shaping the tone.

To be honest, I'm the kind of person who loves "spiffing up" old stuff. I've restored several pieces of woodworking machinery (Old Arn as the afficionados affectionately refer to it) and still have two that see daily use in my shop. It's a challenge and I always learn new skills along the way. I hadn't thought about this being any kind of collector's item as I can find almost nothing about it online. Found a circuit diagram and reference to a couple of old Craigslist listings and that's about it. So, recovering (or building a new cab), replacing the face plate and knobs is just some fun I just can't resist!!

Thanks for the advice re the caps. I see them on the circuit diagram, so I'll definitely take care of that.

Re: Amp restoration

PostPosted: Sun Sep 30, 2018 11:55 am
by Steve Sawyer
Daryl - thanks. That's good info. Did you just take the bare cabinet to the shop to have the bedliner sprayed on? I have that liner in my little Ranger. I'm assuming that you mask off the areas to be kept free of the liner material.

Definitely sounds a heckuva lot easier than wrapping Tolex around it!

I'd still like to explore doing a tweed cover though, if I'm not biting off more than I can chew.

I might do the reverse re the 12"/15" speakers. Someone on a guitar players' forum I frequent suggesting replacing the 15" with a 12" if I re-build the cab. I do want to use this for bass as well, so making an external 12" cabinet with an open back and some way of switching between the two would be slick!

Heck, I could re-imagine this as a "head" and build a 15" and a 12" cabinet too. Interesting thought.

Re: Amp restoration

PostPosted: Sun Sep 30, 2018 12:02 pm
by Daryl Kosinski
I have spent 39 years in repair and calibration of industrial electronics.
"ReCaping" just because it is old I would not advise.
Unless it is humming leave it alone.

Elecrolitic capicators tend to reform when turned on. If no hum the a visual inspection is all thats needed.
If the cap is swollen or showing signs of leaking then replace. Darker color of the circuit board near or under the power rectifiers would also indicate a possiable failing cap.

Re: Amp restoration

PostPosted: Sun Sep 30, 2018 12:04 pm
by Daryl Kosinski
Steve Sawyer wrote:Daryl - thanks. That's good info. Did you just take the bare cabinet to the shop to have the bedliner sprayed on? I have that liner in my little Ranger. I'm assuming that you mask off the areas to be kept free of the liner material.

Definitely sounds a heckuva lot easier than wrapping Tolex around it!

I'd still like to explore doing a tweed cover though, if I'm not biting off more than I can chew.

I might do the reverse re the 12"/15" speakers. Someone on a guitar players' forum I frequent suggesting replacing the 15" with a 12" if I re-build the cab. I do want to use this for bass as well, so making an external 12" cabinet with an open back and some way of switching between the two would be slick!

Heck, I could re-imagine this as a "head" and build a 15" and a 12" cabinet too. Interesting thought.


I used rattle cans from home depot. The cabinets were empty so no masking needed.

I should have used the head with 2 Cabinets idea but it's too late now.

Re: Amp restoration

PostPosted: Sun Sep 30, 2018 12:07 pm
by Daryl Kosinski
I also added a tweeter to the 12 in cabinet.

Re: Amp restoration

PostPosted: Sun Sep 30, 2018 12:34 pm
by Steve Sawyer
Daryl - thanks! Can you recommend a good online resource for info on building speaker cabinets for guitars? The only thing I know about speakers and cabinets is that they make sound... :roll:

Re: Amp restoration

PostPosted: Sun Sep 30, 2018 3:43 pm
by Daryl Kosinski
Steve Sawyer wrote:Daryl - thanks! Can you recommend a good online resource for info on building speaker cabinets for guitars? The only thing I know about speakers and cabinets is that they make sound... :roll:


Not really.

I cut down the chassis of the Sidekick to the smallest size I could then built the cabinet to fit.

The Bass cabinet was sized to fit the 15 inch speaker as small as possiable. Added the bass port.

They both sound pretty good for not even considering acoustic design.

Re: Amp restoration

PostPosted: Sun Sep 30, 2018 8:10 pm
by Steve Sawyer
I was thinking of just sticking with the dimensions of the existing 15" cabinet, so yeah, that part should be easy.

Re: Amp restoration

PostPosted: Sun Sep 30, 2018 10:01 pm
by Mario Proulx
I built myself an amp a while back, but instead of Tolex, I "covered" it with paintable, rubberized automotive undercoating. One can did the trick, even did the interior. For about $12...!

You could strip-off the worn tolex, fill and sand it nicely, and spray it with similar stuff.

Re: Amp restoration

PostPosted: Mon Oct 01, 2018 12:17 am
by Steve Sawyer
Daryl Kosinski wrote:Unless it is humming leave it alone.


Thanks, Daryl. Am I correct that "hum" would be observable with no inputs? I have a LOT of hum at times, but I'm assuming it's from single-coil pickups and a noisy pedal stack! :)

Thanks too for those visual inspection tips!

Re: Amp restoration

PostPosted: Mon Oct 01, 2018 12:28 pm
by Daryl Kosinski
Yes no input.

Also the sniff test. Be sure the capacitors are discharged then stick your nose in the chassis and sniff. Burnt smell not good.

Re: Amp restoration

PostPosted: Tue Oct 02, 2018 7:13 am
by Brian Evans
Only 40 volts on those caps, but they still need to be discharged. Not like a tube amp.

Re: Amp restoration

PostPosted: Tue Oct 02, 2018 9:09 am
by Mark Swanson
Traynor amps are built very well, good amps. No need to rebuild the cabinet! Just clean it up, and the spray coating is a great idea.

Re: Amp restoration

PostPosted: Wed Oct 03, 2018 7:20 pm
by Steve Sawyer
The more I play with this amp, the more I like it.

The only complaint I have so far is that I wish it had an effects loop. The overdrive works very well, but sounds pretty dodgy with a reverb in my pedal stack.

Is anyone around here sufficiently versed in electronics that they could give me some advice on this? See the schematic below. I think the effects loop would have to be placed into the circuit in the region I've indicated with the red box, as I'd want it to be after the distortion circuit and after the EQ (easily spotted by the array of pots to the left of the red box), but BEFORE the balanced line out. My GUESS is that it'd go inline with the output of the TL072 Op Amp I see just above the master volume. I have no idea how difficult that would be to do on the actual circuit board, but I think that might be the spot...

TS-60B_Schematic.png

Re: Amp restoration

PostPosted: Thu Oct 04, 2018 10:21 am
by Brian Evans
It should be really easy to lift the wire to the input of that master volume pot, the wiper of that pot is the output to the power amp. If the op-amp is being run in it's design envelope, it should be putting out around 8 volts peak to peak at most at that point, which might be a little much for pedals that are designed for guitar pickup voltage levels, but should be in the ball park (really hot pickups can put out 1V rms, which is 1.7 volts peak to peak in a sine wave). My take based on 40 year old electronics school...