New Amp or Mod Old One?

Tele56 · October 9th, 2009, 02:55 PM

I'm in the middle of an "amp tone" dilemma. I currently have a tube Works TD-752 which has been fine for the last 2-3 years. But....the reverb is starting to fade in and out (sounds like a new reverb tank is in the future) and the stock speaker is also fading. Would it be worthwhile, both tone-wise and financially, to replace the reverb tank (I have no idea how much that would be) and replace the speaker with a quality Weber or Emminence? The other option is putting the mod money towards a SCXD? I finally have the Tele tone thing solved with my Hwy 1 Texas with OV pups now on to the amp tone. Any advice or suggestions are welcome.

Singin' Dave · October 9th, 2009, 03:01 PM

If you like how the amp sounded, I'd get it fixed, First thing to try is tubes - are you sure your reverb driver tube is OK?

And yes, a new efficient speaker will help a bunch too.

Tele56 · October 9th, 2009, 03:05 PM

Dave the TW sounded OK. I don't know much about amps but the reverb fades in and out without any pattern. Sometimes I can use the amp for hours and the reverb is fine, other times it fades in and out. How much would a new reverb tank cost and is it an easy fix/install?

boomboomba · October 9th, 2009, 03:17 PM

Dave's right, check the tube that drives the reverb. It's a $10 part and they do wear out.

Tele56 · October 9th, 2009, 03:44 PM

boom thanks. Not sure what the reverb tube looks like though.

Singin' Dave · October 9th, 2009, 03:50 PM

They look just like the other preamp tubes and are typically 12AX7's or 12AT7s. You'll need to find a schematic if you can which will tell you which tubes(s) drive the reverb, if indeed that amp has tube driven reverb.

I'm not too familiar with that amp - does it have 2 preamp tubes and a SS power section (i.e. no power tubes)?

Wally · October 9th, 2009, 03:52 PM

When I googled 'tube works TD-752', I got links that show this to be a Genz-Benz amp and to be a solid state amp with a single 12AX7 tube in the preamp..switchable in and out. Is this the amp referred to? IF so, everything including the reverb is done in the SS domain except for that one tube that is used as an OD/boost/warming function, right?
IF there is some other Tube Works TD-752 amp, I apologize for the interruption.
IF this is the amp, then the reverb problems are in the SS reverb circuit, I would think, and may be heat-related....some component going out of spec when heated up???
It would surprise me if the problem were in the tank going by the description of the reverb's problem.

Tele56 · October 9th, 2009, 03:58 PM

Wally that would be the correct model (Tube Works TD-752). Seems to have a lot of design similarities with the SCXD (except for the voicings). If the problem is in the SS circuit how would that be fixed???

Tele56 · October 9th, 2009, 04:23 PM

Dave I'm going to check the amp and maybe post a pic or two. Unfortunately I don't know the difference between a 12AX7 tube or a XYZ123 tube!

Wally · October 9th, 2009, 04:30 PM

Tele56, it is tech time. IF you do your own work, then get a schematic and pile off into it. INtermittent problems are the worst kind. IF you wait for the reverb to stop completely, it may be a while. That amp may be old enough that a cap is going weird. An IC may be heat sensitive. A resistor may be heat sensitive. Bunch of fun.
PCB's are headaches to work on. SS?? ....if you like it, fix it.
My personal opinion is that a guitarist should own only one SS amp in their life, and that would be an inexpensive amp to get them started. Even for a beginner, I prefer tubes.
But....that is a personal thing.
Being that I am using large quantities of profanity today on a JCM 2000 DSL, I am not big on PCB amps, either. Someone hand me a 12 gauge, please. I think I know how to fix this thing! LOL

Tele56 · October 9th, 2009, 04:41 PM

Wally I'm not too amp-technically inclined. Sorry to hear about your DSL dilemma. BTW, I do have an extra 12 ga. if you need it!!!

Wally · October 9th, 2009, 05:50 PM

TEle56, it is tech time, then, for that G-B TD-752...if you like it enough to pay the bill for the fix.
RE: the JCM 2000....I knew better than to fall off into it! My bad!

October 9th, 2009, 02:55 PM	#1 (permalink)
Tele56 Tele-Meister Join Date: Nov 2005 Location: Arizona USA Age: 50 Posts: 203	New Amp or Mod Old One? I'm in the middle of an "amp tone" dilemma. I currently have a tube Works TD-752 which has been fine for the last 2-3 years. But....the reverb is starting to fade in and out (sounds like a new reverb tank is in the future) and the stock speaker is also fading. Would it be worthwhile, both tone-wise and financially, to replace the reverb tank (I have no idea how much that would be) and replace the speaker with a quality Weber or Emminence? The other option is putting the mod money towards a SCXD? I finally have the Tele tone thing solved with my Hwy 1 Texas with OV pups now on to the amp tone. Any advice or suggestions are welcome. __________________ Standing on a corner in Winslow Arizona

October 9th, 2009, 03:05 PM	#3 (permalink)
Tele56 Tele-Meister Join Date: Nov 2005 Location: Arizona USA Age: 50 Posts: 203	Dave the TW sounded OK. I don't know much about amps but the reverb fades in and out without any pattern. Sometimes I can use the amp for hours and the reverb is fine, other times it fades in and out. How much would a new reverb tank cost and is it an easy fix/install? __________________ Standing on a corner in Winslow Arizona

October 9th, 2009, 03:44 PM	#5 (permalink)
Tele56 Tele-Meister Join Date: Nov 2005 Location: Arizona USA Age: 50 Posts: 203	boom thanks. Not sure what the reverb tube looks like though. __________________ Standing on a corner in Winslow Arizona

October 9th, 2009, 03:58 PM	#8 (permalink)
Tele56 Tele-Meister Join Date: Nov 2005 Location: Arizona USA Age: 50 Posts: 203	Wally that would be the correct model (Tube Works TD-752). Seems to have a lot of design similarities with the SCXD (except for the voicings). If the problem is in the SS circuit how would that be fixed??? __________________ Standing on a corner in Winslow Arizona

October 9th, 2009, 04:23 PM	#9 (permalink)
Tele56 Tele-Meister Join Date: Nov 2005 Location: Arizona USA Age: 50 Posts: 203	Dave I'm going to check the amp and maybe post a pic or two. Unfortunately I don't know the difference between a 12AX7 tube or a XYZ123 tube! __________________ Standing on a corner in Winslow Arizona

October 9th, 2009, 03:01 PM	#2 (permalink)
Singin' Dave Tele-Afflicted Join Date: May 2008 Location: Chicago Age: 41 Posts: 1,052	If you like how the amp sounded, I'd get it fixed, First thing to try is tubes - are you sure your reverb driver tube is OK? And yes, a new efficient speaker will help a bunch too.

October 9th, 2009, 03:17 PM	#4 (permalink)
boomboomba Tele-Meister Join Date: Aug 2009 Location: Montréal Age: 45 Posts: 133	Dave's right, check the tube that drives the reverb. It's a $10 part and they do wear out.

October 9th, 2009, 03:50 PM	#6 (permalink)
Singin' Dave Tele-Afflicted Join Date: May 2008 Location: Chicago Age: 41 Posts: 1,052	They look just like the other preamp tubes and are typically 12AX7's or 12AT7s. You'll need to find a schematic if you can which will tell you which tubes(s) drive the reverb, if indeed that amp has tube driven reverb. I'm not too familiar with that amp - does it have 2 preamp tubes and a SS power section (i.e. no power tubes)?

October 9th, 2009, 03:52 PM	#7 (permalink)
Wally Poster Extraordinaire Join Date: Mar 2003 Location: Lubbock, TX Posts: 6,012	When I googled 'tube works TD-752', I got links that show this to be a Genz-Benz amp and to be a solid state amp with a single 12AX7 tube in the preamp..switchable in and out. Is this the amp referred to? IF so, everything including the reverb is done in the SS domain except for that one tube that is used as an OD/boost/warming function, right? IF there is some other Tube Works TD-752 amp, I apologize for the interruption. IF this is the amp, then the reverb problems are in the SS reverb circuit, I would think, and may be heat-related....some component going out of spec when heated up??? It would surprise me if the problem were in the tank going by the description of the reverb's problem.

October 9th, 2009, 04:30 PM	#10 (permalink)
Wally Poster Extraordinaire Join Date: Mar 2003 Location: Lubbock, TX Posts: 6,012	Tele56, it is tech time. IF you do your own work, then get a schematic and pile off into it. INtermittent problems are the worst kind. IF you wait for the reverb to stop completely, it may be a while. That amp may be old enough that a cap is going weird. An IC may be heat sensitive. A resistor may be heat sensitive. Bunch of fun. PCB's are headaches to work on. SS?? ....if you like it, fix it. My personal opinion is that a guitarist should own only one SS amp in their life, and that would be an inexpensive amp to get them started. Even for a beginner, I prefer tubes. But....that is a personal thing. Being that I am using large quantities of profanity today on a JCM 2000 DSL, I am not big on PCB amps, either. Someone hand me a 12 gauge, please. I think I know how to fix this thing! LOL

October 9th, 2009, 04:41 PM	#11 (permalink)
Tele56 Tele-Meister Join Date: Nov 2005 Location: Arizona USA Age: 50 Posts: 203	Wally I'm not too amp-technically inclined. Sorry to hear about your DSL dilemma. BTW, I do have an extra 12 ga. if you need it!!! __________________ Standing on a corner in Winslow Arizona

October 9th, 2009, 05:50 PM	#12 (permalink)
Wally Poster Extraordinaire Join Date: Mar 2003 Location: Lubbock, TX Posts: 6,012	TEle56, it is tech time, then, for that G-B TD-752...if you like it enough to pay the bill for the fix. RE: the JCM 2000....I knew better than to fall off into it! My bad!

IMPORTANT:Treat everyone here with respect, no matter how difficult! No sex, drug, political, religion or hate discussion permitted here.