[jefkahn]

I'm in the market for a used Twin Reverb, 60s or 70s. Any advice on what to look for to make sure it's all good inside? How do I know that parts haven't been swapped out, etc.? I'd be OK if you sent me a good resource on the web or described things here. This is of course especially important when looking over photos from eBay.

ps. I know some of you have opinions about BF instead of SF, non-master volume over master-volume Twin, etc. I'm interested in those opinions, but I'm mainly interested in how to make sure that all components are original and good-quality when looking over amps.

Thanks.
Jef

[WilliamC]

Since nobody jumped in last night...

First, the time period you mention covers several rather different Twin Reverb amps: the "original" 85 watt (blackface), the silver/blackface transition, the 100 watt, the master volume 100 watt and the 135 watt. You'll want to try some out locally to see which general variety of Twin suits you and your equipment. Many people will suggest that any Twin older than May 1968 (when the silver face went to the AC568 circuit) are the most desirable.

Now, on a 35-45 year old amp there are quite a few things that you WANT to be swapped out: power supply capacitors, bypass caps in the pre-amp, power tubes (6L6), some of the pre-amp tubes (12AX7, 12AT7), possibly speakers (unless they're JBLs which are worth re-coning if they need it). If the amp is a bit on the older side, it will have carbon composition resistors which should also be checked for value.

In a perfect world the seller will be able to document what was done and when. In a really perfect world you'll be able to try the amp before you spend your cash.

Oh and they weigh 65-70 pounds so shipping may be a bit expensive!

[Tennessee Jedi]

http://www.ampwares.com/
a handy guide

[JonnyBoy]

Fabulous amps. All have their good and bad points as they evolved. I was in the same place as you, then I realized to get closest within the "Desirable" region from stock, the '65 reissues made sense. Some have said they don't prefer the remake, but it is as Fender says it is a "Reissue of the 1965 twin reverb circuit". Same circuit, but different type of board. I love mine, I am looking to modify it to tap the preamp and upgrade the the suggested caps, resistors, etc.. It is an awesome amp the way it is, I am excited to see it improved from here. This amps lineage is weird in the way that it is considered best before they tried to make it better through out the years, but the upgrades like a master volume and higher wattage may be something you desire and like. The suggestion of going around town and testing them is a great idea. They can all be modified to get the tone to where you want it with a good amp guy in the end. The best twin is a good working one with good speakers for a great price, imo. The reissues with the eminence speakers, I don't prefer (speakers), The Jensen's sound better to me. I got the latter, but I play through a HT like cab with 225watt commonwealth's, bypass the eminence stock speakers and it is great.