weber Copper Cap in a '61 Ampeg?

AnArmyOfJuan · May 2nd, 2008, 03:07 PM

I just received the Weber WY3GT copper cap I had on order. I haven't tried it in the amp yet, but I wanted some opinions.

I completely retubed my '61 Ampeg Reverberocket last night, aside from the rectifier. I talked to a tech earlier in the day, and he recommended against using a copper cap, though, of course, i already had it on order before i talked to him. he stated that it warmed up too quickly for the amp, since it doesn't have a standby switch. then again, he didn't know what tube went in there, anyway, but I suppose I can't expect anyone to pull that information out at the drop of a hat.

my question is: will i harm my amp by using a coppercap? what are the drawbacks/benefits?

should I just leave the Sovtek 5Y3 in there, since it's working right now, and save the CC as a backup?

I'm kind of confused. I don't want to damage my amp. I just want it to be as reliable as possible.

mark norwine · May 2nd, 2008, 04:30 PM

As a general rule, it's not a great idea to hit cold power tubes (or even preamp tubes for that matter) with high voltage.

With a glass rectifier, there's no high voltage until the rectifier tube heats up. By that time, the other tubes are warm....maybe not fully hot, but warmed up nicely.

A solid state rectifier delivers high DC voltage immediately. With no standby switch, you're hitting cold tubes with high voltage.

The copper cap is designed to mimic the sag of a glass rectifier tube, but is ultimately a solid state rectifier. It will present high voltage to your cold tubes immediately on startup. This is why your tech is recommending against its use. I concur.

In fairness, many old ampegs were built with ss (diode) rectifiers & no standby switch. My all-time fave amp (GS12-R) is that way. I've been smacking cold tubes for years....but it's still not a great idea.

If my amp had a glass rectifier & no standby switch, I'd stick with glass.

EDIT....That said, I wouldn't use a sovtek 5Y3 ever. Ever measured the forward Vdrop characteristics of one? It bears little resemblance to the specs of a 5Y3. And, after all, NOS American 5Y3 tubes are cheap & plentiful.

Scott S · May 2nd, 2008, 06:48 PM

Opinions differ on whether significant cathode poisoning happens in guitar amps, but if you're really worried and don't want to install a standby switch, throw in a 6106 rectifier.

- Scott

eugenedunn · May 2nd, 2008, 11:57 PM

Copper Caps have some in-rush current resistance built-in, so there is NOT an immediate power tube exposure to high voltage. Weber says that the delay is in the 1-2 second range rather than the 7-9 second range of a glass rectifier. Lot's of people use them successfully. I think it's worth a try.

I see lots of positive comments with people using them in high fidelity tube amps like the Dynaco ST-70's....

Caution needs to be exercised to make sure that any new stiffer rectifier might present too much voltage to the tubes, making them red plate or worse.

tele_jas · May 3rd, 2008, 01:22 AM

I ran one in a Dr. Z for a while and liked it, but I realized I liked the warmer tube GZ34 better.

Benefits...... Reliability, tighter sound

Against...... Not quite as "warm" as a tube rectifier, a little more top end breakup.

The tone was probably no different than if I switched rectifier tubes, but I like my JJ rectifier better..... just a warmer tone, seems to have more "compression" on tap. And it seems to have a less aggressive top end breakup.

That's just what I heard..... I'm keeping my copper cap for a backup, as I could get buy with one for a long time if I needed to.

copper cap = good, but not for everyone.

eugenedunn · May 3rd, 2008, 09:52 AM

Hey Tele Jas,

Did you run a WZ34 in that Dr. Z amp? I've thought about trying the WZ68 after Ted Weber suggested I try it for more "low end oomph". It is essentially a double-dose WZ34 with the same voltage drop.

I haven't seen much comment on that particular model, except in Hi-Fi tube audio forums.... where some people swear by them for the clean response and reliability factor.

tele_jas · May 3rd, 2008, 10:27 AM

Yeah, it was a WZ34.... I may look in to the WZ68 and give it a shot. Heck, for $20-$25 you can't go wrong having a reliable backup and something to expieriment with?!?!

eugenedunn · May 3rd, 2008, 11:27 AM

Hey Tele Jas,

Didja ever have to adjust bias when you changed to that Copper Cap? No red plating of the power tubes observed?

Although these models are supposed to be direct replacements, even tube rectifiers can differ from brand to brand.

One thing is that they are supposed to be heavier than regular glass tube rectifiers, so in some Fender amp models where the tubes hang upside down, you have to be sure your tube sockets are tight enough to hold the heavier Copper Cap in there during amp moves.

I just had my Princeton Reverb recapped and the sockets retensioned. Man some of my old Fenders have the LOOSEST sockets you can imagine.

I hope someone else will post a comment on the WZ68 model....

eugenedunn · May 5th, 2008, 09:46 PM

Well, from a reliability standpoint, you're never gonna experience a blown Copper Cap during a gig..... so that's a good thing. And potentially one less component to worry about when transporting your tube amp to the next venue.

Could be a good thing. I was hoping that the WZ68 would be a close drop-in replacement for my GZ34 tube, if I needed a backup. But I haven't seen any comments negative or positive about that model in guitar amps.

May 2nd, 2008, 03:07 PM	#1 (permalink)
AnArmyOfJuan TDPRI Member Join Date: Mar 2007 Location: Detroit, MI Age: 33 Posts: 77 6 Photos	weber Copper Cap in a '61 Ampeg? I just received the Weber WY3GT copper cap I had on order. I haven't tried it in the amp yet, but I wanted some opinions. I completely retubed my '61 Ampeg Reverberocket last night, aside from the rectifier. I talked to a tech earlier in the day, and he recommended against using a copper cap, though, of course, i already had it on order before i talked to him. he stated that it warmed up too quickly for the amp, since it doesn't have a standby switch. then again, he didn't know what tube went in there, anyway, but I suppose I can't expect anyone to pull that information out at the drop of a hat. my question is: will i harm my amp by using a coppercap? what are the drawbacks/benefits? should I just leave the Sovtek 5Y3 in there, since it's working right now, and save the CC as a backup? I'm kind of confused. I don't want to damage my amp. I just want it to be as reliable as possible. __________________ Pat V. and the Detroit 3

May 2nd, 2008, 04:30 PM	#2 (permalink)
mark norwine Tele-Afflicted Join Date: Mar 2003 Location: New Jersey Age: 50 Posts: 1,359	As a general rule, it's not a great idea to hit cold power tubes (or even preamp tubes for that matter) with high voltage. With a glass rectifier, there's no high voltage until the rectifier tube heats up. By that time, the other tubes are warm....maybe not fully hot, but warmed up nicely. A solid state rectifier delivers high DC voltage immediately. With no standby switch, you're hitting cold tubes with high voltage. The copper cap is designed to mimic the sag of a glass rectifier tube, but is ultimately a solid state rectifier. It will present high voltage to your cold tubes immediately on startup. This is why your tech is recommending against its use. I concur. In fairness, many old ampegs were built with ss (diode) rectifiers & no standby switch. My all-time fave amp (GS12-R) is that way. I've been smacking cold tubes for years....but it's still not a great idea. If my amp had a glass rectifier & no standby switch, I'd stick with glass. EDIT....That said, I wouldn't use a sovtek 5Y3 ever. Ever measured the forward Vdrop characteristics of one? It bears little resemblance to the specs of a 5Y3. And, after all, NOS American 5Y3 tubes are cheap & plentiful. __________________ "Progress is not possible without deviation from the norm." Frank Zappa

May 2nd, 2008, 11:57 PM	#4 (permalink)
eugenedunn Tele-Holic Join Date: Dec 2006 Location: Sacramento, CA Age: 54 Posts: 598 33 Photos	Copper Caps have some in-rush current resistance built-in, so there is NOT an immediate power tube exposure to high voltage. Weber says that the delay is in the 1-2 second range rather than the 7-9 second range of a glass rectifier. Lot's of people use them successfully. I think it's worth a try. I see lots of positive comments with people using them in high fidelity tube amps like the Dynaco ST-70's.... Caution needs to be exercised to make sure that any new stiffer rectifier might present too much voltage to the tubes, making them red plate or worse. __________________ Ono Boy says "good n' swampy....."

May 3rd, 2008, 01:22 AM	#5 (permalink)
tele_jas Tele-Meister Join Date: Feb 2006 Location: Springfield/Mt.Vernon, MO Age: 36 Posts: 373 12 Photos	I ran one in a Dr. Z for a while and liked it, but I realized I liked the warmer tube GZ34 better. Benefits...... Reliability, tighter sound Against...... Not quite as "warm" as a tube rectifier, a little more top end breakup. The tone was probably no different than if I switched rectifier tubes, but I like my JJ rectifier better..... just a warmer tone, seems to have more "compression" on tap. And it seems to have a less aggressive top end breakup. That's just what I heard..... I'm keeping my copper cap for a backup, as I could get buy with one for a long time if I needed to. copper cap = good, but not for everyone. __________________ *Dr. Z Stangray & Z 2x12 cab Dr. Z Mazerati * 2 tele's * Some pedals * ect...** Good deals with: tweeddeluxe, Lwilliams, Sunkidd www.markchapmanband.com www.myspace.com/themcb www.guitartest.moonfruit.com

May 3rd, 2008, 09:52 AM	#6 (permalink)
eugenedunn Tele-Holic Join Date: Dec 2006 Location: Sacramento, CA Age: 54 Posts: 598 33 Photos	Hey Tele Jas, Did you run a WZ34 in that Dr. Z amp? I've thought about trying the WZ68 after Ted Weber suggested I try it for more "low end oomph". It is essentially a double-dose WZ34 with the same voltage drop. I haven't seen much comment on that particular model, except in Hi-Fi tube audio forums.... where some people swear by them for the clean response and reliability factor. __________________ Ono Boy says "good n' swampy....."

May 2nd, 2008, 06:48 PM	#3 (permalink)
Scott S Tele-Afflicted Join Date: Dec 2005 Location: SW CR IA US NA PE Age: 27 Posts: 1,176	Opinions differ on whether significant cathode poisoning happens in guitar amps, but if you're really worried and don't want to install a standby switch, throw in a 6106 rectifier. - Scott

May 3rd, 2008, 10:27 AM	#7 (permalink)
tele_jas Tele-Meister Join Date: Feb 2006 Location: Springfield/Mt.Vernon, MO Age: 36 Posts: 373 12 Photos	Yeah, it was a WZ34.... I may look in to the WZ68 and give it a shot. Heck, for $20-$25 you can't go wrong having a reliable backup and something to expieriment with?!?! __________________ *Dr. Z Stangray & Z 2x12 cab Dr. Z Mazerati * 2 tele's * Some pedals * ect...** Good deals with: tweeddeluxe, Lwilliams, Sunkidd www.markchapmanband.com www.myspace.com/themcb www.guitartest.moonfruit.com

May 3rd, 2008, 11:27 AM	#8 (permalink)
eugenedunn Tele-Holic Join Date: Dec 2006 Location: Sacramento, CA Age: 54 Posts: 598 33 Photos	Hey Tele Jas, Didja ever have to adjust bias when you changed to that Copper Cap? No red plating of the power tubes observed? Although these models are supposed to be direct replacements, even tube rectifiers can differ from brand to brand. One thing is that they are supposed to be heavier than regular glass tube rectifiers, so in some Fender amp models where the tubes hang upside down, you have to be sure your tube sockets are tight enough to hold the heavier Copper Cap in there during amp moves. I just had my Princeton Reverb recapped and the sockets retensioned. Man some of my old Fenders have the LOOSEST sockets you can imagine. I hope someone else will post a comment on the WZ68 model.... __________________ Ono Boy says "good n' swampy....."

May 5th, 2008, 09:46 PM	#9 (permalink)
eugenedunn Tele-Holic Join Date: Dec 2006 Location: Sacramento, CA Age: 54 Posts: 598 33 Photos	Well, from a reliability standpoint, you're never gonna experience a blown Copper Cap during a gig..... so that's a good thing. And potentially one less component to worry about when transporting your tube amp to the next venue. Could be a good thing. I was hoping that the WZ68 would be a close drop-in replacement for my GZ34 tube, if I needed a backup. But I haven't seen any comments negative or positive about that model in guitar amps. __________________ Ono Boy says "good n' swampy....."