Trace Elliot Twin Valve Combo

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FWIW, I got both of my Twin Valve Combos (one of which has been converted to a head and separate cab) from Steve Azola, who had loaded each of them with the GE's, so I have not tried either Twin Valve with different tubes. That being said, I have owned a Quatra Valve and a Hexa Valve which had non-GE power tubes, and they did not sound as good as the Twins with the GE's, but there may be other reasons for this. Those GE's are crazy expensive nowadays, so I'd be tempted to just roll with what is in it now, unless they cause any problems. I'm sure it sounds fantastic as is.

It had the original Trace tubes but on its way here from Europe o e of the tubes was shattered. I had put in some KT88s but my tech thought a small amp like that wouldn’t make the best use of the KTs so I’m searching for some 6550s to put in it.

I got a V4 recently that was NOS and a few weeks into owning it it blew a fuse. Took it to the tech fearing the worst because it was NOS. He said the bias was too hot so he biased it properly. I thought it was going to have to be recapped at a minimum but wasn’t the case. Long story short from this detour, I learned my lesson with tubes, if I buy something new or new to me, get it checked out before putting it into circulation. Good thing I did, turns out it’s wired for European current (220v) but he went ahead and rewired and all’s good now.

I may just go w some middle of the road tubes w the Twin here and splurge on tubes for one of my more power full tube amps (DB728, DB359, V4 or SA200). My tech seems to think it won’t make a huge difference between mid priced tubes vs premium.

@tombowlus thank you your great insight.

 

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It had the original Trace tubes but on its way here from Europe o e of the tubes was shattered. I had put in some KT88s but my tech thought a small amp like that wouldn’t make the best use of the KTs so I’m searching for some 6550s to put in it.

I got a V4 recently that was NOS and a few weeks into owning it it blew a fuse. Took it to the tech fearing the worst because it was NOS. He said the bias was too hot so he biased it properly. I thought it was going to have to be recapped at a minimum but wasn’t the case. Long story short from this detour, I learned my lesson with tubes, if I buy something new or new to me, get it checked out before putting it into circulation. Good thing I did, turns out it’s wired for European current (220v) but he went ahead and rewired and all’s good now.

I may just go w some middle of the road tubes w the Twin here and splurge on tubes for one of my more power full tube amps (DB728, DB359, V4 or SA200). My tech seems to think it won’t make a huge difference between mid priced tubes vs premium.

@tombowlus thank you your great insight.

If the V4 was wired for 220V, IMHO this is probably why it blew the fuse. If no other damage occurred, you got lucky. Hopefully the fuse shorted extremely fast, as any damage that did occur would be become progressively worse over a very short time.

As far as KT88 VS 6550 in the Twin. If you want to save money and have some decent tubes in-hand, have the tech bias the amp for KT88 (treat it as a 35W tube). The only benefit may be you don't have to spend money on another set of tubes.

As I mentioned in the other thread, Trace Elliot used the same basic output section (including the same output transformer) over multiple generations of tube amps. Some series of amps ran KT88 and some ran 6550, so I believe the circuit will work fine with either tube type.

The amp may sound slightly different, or it may not. I have pretty limited experience rolling output tubes. My DB359 has Svetlana 6550Cs. I believe these are the older Winged-Cs version **. For fun I rolled a set of JJ KT88s into the DB359. I didn't hear any difference in tone. So in this case, 6550 and KT88 sounded exactly alike.

** If you don't know Cyrillic C is Roman S. New Sensor registered the trade name Svetlana in the US. Due to this, the original Svetlanas were renamed Winged-C.
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I have a Matchless Thunderchief that originally came with Shuguang KT100. KT100 was a robust KT88 variant that is now obsolete. The stock bias on the Thunderchief is very hot, and the amp has a tendency to eat output tubes. After the KT100s burned up, I ran some JJs for a few months. Then, I decided to try some Shuguang GEKT88s. These are special production run tubes with a 50W dissipation rating, which I hoped would be more stable in the amp, which they were not.

To my ears the JJs sounded better than the Shuguangs, although I was able to minimize the difference by adjusting the bias. I thought the JJs sounded better biased fairly hot. If I cooled the bias down, the Shuguangs sounded closer to the JJs, but not identical. So in this case, there was noticeable variance between different brands of KT88.

If there is any variance between the tubes, which tube is best depends on what your tone goals are. It's possible you would prefer the Shuguangs in the Thunderchief.

It's not a good time to buy tubes due to a couple of factors. Shuguang had a fire a few years back and AFAIK they are no longer making tubes. New Sensor is a Russian company, and prices for New Sensor tubes has pretty much doubled since the invasion of Ukraine. Of the big three tube companies, JJ has been impacted the least. Tubes & More was selling JJ 6550 for a decent price, but are now out of stock. Eurotubes may have stock and their prices are not as bad as other common sources.

Psvane has introduced a line of tubes to fill the gap left by Shuguang. They offer a 6550A. AFAIK these tubes have not been in the market long enough to have established a proven reliability rating, but you could try a pair. Tubes & More is selling them at a decent price, but the price has risen over the last few months.

 

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If the V4 was wired for 220V, IMHO this is probably why it blew the fuse. If no other damage occurred, you got lucky. Hopefully the fuse shorted extremely fast, as any damage that did occur would be become progressively worse over a very short time.

As far as KT88 VS 6550 in the Twin. If you want to save money and have some decent tubes in-hand, have the tech bias the amp for KT88 (treat it as a 35W tube). The only benefit may be you don't have to spend money on another set of tubes.

As I mentioned in the other thread, Trace Elliot used the same basic output section (including the same output transformer) over multiple generations of tube amps. Some series of amps ran KT88 and some ran 6550, so I believe the circuit will work fine with either tube type.

The amp may sound slightly different, or it may not. I have pretty limited experience rolling output tubes. My DB359 has Svetlana 6550Cs. I believe these are the older Winged-Cs version **. For fun I rolled a set of JJ KT88s into the DB359. I didn't hear any difference in tone. So in this case, 6550 and KT88 sounded exactly alike.

** If you don't know Cyrillic C is Roman S. New Sensor registered the trade name Svetlana in the US. Due to this, the original Svetlanas were renamed Winged-C.
​

I have a Matchless Thunderchief that originally came with Shuguang KT100. KT100 was a robust KT88 variant that is now obsolete. The stock bias on the Thunderchief is very hot, and the amp has a tendency to eat output tubes. After the KT100s burned up, I ran some JJs for a few months. Then, I decided to try some Shuguang GEKT88s. These are special production run tubes with a 50W dissipation rating, which I hoped would be more stable in the amp, which they were not.

To my ears the JJs sounded better than the Shuguangs, although I was able to minimize the difference by adjusting the bias. I thought the JJs sounded better biased fairly hot. If I cooled the bias down, the Shuguangs sounded closer to the JJs, but not identical. So in this case, there was noticeable variance between different brands of KT88.

If there is any variance between the tubes, which tube is best depends on what your tone goals are. It's possible you would prefer the Shuguangs in the Thunderchief.

It's not a good time to buy tubes due to a couple of factors. Shuguang had a fire a few years back and AFAIK they are no longer making tubes. New Sensor is a Russian company, and prices for New Sensor tubes has pretty much doubled since the invasion of Ukraine. Of the big three tube companies, JJ has been impacted the least. Tubes & More was selling JJ 6550 for a decent price, but are now out of stock. Eurotubes may have stock and their prices are not as bad as other common sources.

Psvane has introduced a line of tubes to fill the gap left by Shuguang. They offer a 6550A. AFAIK these tubes have not been in the market long enough to have established a proven reliability rating, but you could try a pair. Tubes & More is selling them at a decent price, but the price has risen over the last few months.

It was actually the Twin Valve that was wired for 220. The V4 was fine thankfully, tech said there’s three fuses at different points in the circuit and the one that blew is the first one in the sequence.

I’ll probably just get JJs.