[Counterstriker]

So the tubes that are in it are stock, from 73.... I wanna buy replacements but I don't know what I'm looking for. I do have a question though, this is probably a stupid one though, but do the tubes have an effect on the tone? Like some tubes have a warmer sound, some Brighter? Thanks!

[NeebruM]

oh hell yes!

Here's a good solid guy who knows and can help you:
http://kcanostubes.com/content/Default.asp

[gr8fullfred]

Hey Dude,

If I am reading your post correctly you are stating that the tubes in your 1973 twin are original?

If so, either the amp has not been played, or chances are at least one tube could be bad.

My advise would be to take it to a really good tube amp guy. Have him go over the whole amp and tune it up.
Every fifteen years or so TRs need new caps. Things drift. Bias needs to be set.
You really can't just change a tube or two and expect the amp to sound its best.
Its so freaking worth it to do this.
I know a great tube amp guy, he is so good its fun just to drop off your amp there, just to see what else is in his shop!
Its like a vintage amp museum. He does great work, everything is always perfect. Worth every penny.
Fred

[jackr]

Here is another really good place for tubes with some knowledgeable guys.

www.eurotubes.com

I also agree with taking it to an amp tech.

[Grateful Dad]

Yeah, I agree w/jackr, www.eurotubes.com is a good place to go for tubes and information. You can talk to him directly and he can provide you with a detailed breakdown of the types of tubes you need, their specs, and the choices available to you. He supplies me with tubes for my Mesa 400+ bass head and I have had positive results dealing with him and his company. I recommend you at least check out the website and email your particular situation to him, he'll respond and tell you what you need at no obligation

[strumminsix]

dude, i bet your preamp tubes are fine and you should keep those! maybe new poweramp tubes

[Imagined Days]

7581A's! Pricey, but great in that amp! Lord Valve hooked me up with a Quad back in 02', they still sound awesome!

[jonarobb]

Here is another really good place for tubes with some knowledgeable guys.

http://www.eurotubes.com

I also agree with taking it to an amp tech.

I recommend using Eurotubes as a last resort. I also strongly recommend staying away from their package tube deals in relation to your amp. The JJ ECC 83/12AX7 have a higher than average failure rate. Most notably in the filaments. This, compounded with JJ's mediocre 6L6GC power tube, will be a waste of dollars.

I highly recommend using Tube Depot (www.tubedepot.com) and doing a little homework on the various tube flavors. A good current production power tube for a Twin Reverb is the Tung Sol 6L6-STR. Tube Depot also has a great deal currently on USA made Philips and Sylvania 12AT7 driver preamp tubes, 5/$40.

I have nothing against Eurotubes. I have extensive tube buying knowledge and keep my ear to the ground about production techniques, variances, etc.... The JJ brand tube has really tanked in the quality dept over the last 18-24 mos.

[jeffm725]

I highly recommend using Tube Depot (http://www.tubedepot.com) and doing a little homework on the various tube flavors. A good current production power tube for a Twin Reverb is the Tung Sol 6L6-STR. Tube Depot also has a great deal currently on USA made Philips and Sylvania 12AT7 driver preamp tubes, 5/$40.

I have nothing against Eurotubes. I have extensive tube buying knowledge and keep my ear to the ground about production techniques, variances, etc.... The JJ brand tube has really tanked in the quality dept over the last 18-24 mos.

+1 on Tube Depot and +100 specifically on the Tung Sol 6L6 STR's , I have them in my Twin and my Boogie, They are great in my Twin,my main tube; they are more than decent in my Boogie and I use them as a backup there(but I got a hold of some NOS Sylvania's that my Boogie LOVES)

[Imagined Days]

Oh, and try Mullard 12AT7's and shuguang 12AX7's. I use these preamp tubes along with my Phillips ECG 7581A power tubes in my Twin and it sings.

[NeebruM]

The advice is +1 for a good amp tech.
any new tubes and for that matter the old ones if they are still good would require re biasing I'm sure at the minimum.

If you don't know how STAY OUT of that amp or it just may be the last thing you do as your world lights up and then goes black.