[UntilThen]

God I love this tube!

I love all my 6SL7 tubes and I only need one.

Tung Sol 6SU7gty
Sylvania 6SL7gt vt-229
Brimar 6SL7gt red letters
RCA 5691 red base

 

[normie610]

I love all my 6SL7 tubes and I only need one.

Tung Sol 6SU7gty
Sylvania 6SL7gt vt-229
Brimar 6SL7gt red letters
RCA 2961 red base

You mean the RCA 5691 red base?

Yeah I have too many 6SL7 tubes now but lucky you, you only need 1 piece for Odyssey right? I need a pair for my preamp, so it doubles the cost every time I’m buying them

Tung Sol VT 229 factory matched pair
Tung Sol 6SU7GTY
RCA Red Base 5691
Linlai E-6SL7
Brimar 6SL7GT (current favorite)
Fivre 6SL7GT
MELZ 6N9S (this one still on the way though)
Shuguang WE6SL7 Plus

 

[UntilThen]

You mean the RCA 5691 red base?

Yes my typo error. Mine is GE branded and it's the only 6SL7 that I have a pair.

Do you have a picture of your Brimar 6SL7GT, seeing it's your favorite.

This is mine.

 

[normie610]

Do you have a picture of your Brimar 6SL7GT, seeing it's your favorite.

You can find the picture here:

https://www.head-fi.org/threads/hea...t-for-all-300b-tube-amps.962932/post-17151351

Mine is with white letters though.

 

[Isaacc7]

All this talk about rectifiers has me wondering again, what is the casual mechanism of different brand rectifiers changing the sound? I understand changing operating points of tubes changing the sound but I don't understand how a Mullard vs. RCA of the same type rectifier can change the sound assuming they are both adhering to the specs. A power supply, including the diodes, is supposed to be providing DC to the amplification circuit. DC is the absence of signal electrically. I know just enough to be dangerous with topics like this but it's my understanding that the diodes used , whether solid state or tube, are not as important to the power supply as the choke and power transformer.

So what gives? I have not noticed any difference between an RCA and EH (Russian) 5u4gt and most of my previous amps have had solid state power supplies.

 

[Isaacc7]

All this talk about rectifiers has me wondering again, what is the casual mechanism of different brand rectifiers changing the sound? I understand changing operating points of tubes changing the sound but I don't understand how a Mullard vs. RCA of the same type rectifier can change the sound assuming they are both adhering to the specs. A power supply, including the diodes, is supposed to be providing DC to the amplification circuit. DC is the absence of signal electrically. I know just enough to be dangerous with topics like this but it's my understanding that the diodes used , whether solid state or tube, are not as important to the power supply as the choke and power transformer.

So what gives? I have not noticed any difference between an RCA and EH (Russian) 5u4gt and most of my previous amps have had solid state power supplies.

I've been in conversation with someone about this. I also realized @SonicTrance went over this with me too I think. The fact that rectifiers can impact sound quality means that the power supply is letting stuff through and not giving pure DC to the amplification circuit. Regulating the supply would cure that but then it doesn't make any sense to use a tube to do rectification. So in rather circular fashion tube rectifiers can change the sound because the circuits that use them are susceptible to changes to the rectifier lol.

 

[senseitedj]

Put the telly on the scales last night. Just thought I'd share incase you're wondering about its weight with 5 tubes. It weighs 21.15 kg

Might be useful when getting a quote for cargo or for selecting audio furniture. The box next to the scales is not from the telly.

 

[UntilThen]

I'm a bit surprised it's not 30 kgs because Odyssey feels like it and I'm sure Telemachus is heavier than Odyssey.

 

[senseitedj]

I'm a bit surprised it's not 30 kgs because Odyssey feels like it and I'm sure Telemachus is heavier than Odyssey.

Put it on the scales mate and find out.

Most of the weight on the telly is on the transformers. Everything is else is quite reasonable

 

[UntilThen]

Put it on the scales mate and find out.

Most of the weight on the telly is on the transformers. Everything is else is quite reasonable

I don't have such scale. Odyssey's weight is also on the transformers. It's tilted backwards when you carry it. I had a Sansui 907mr before that weighs 31 kgs and that almost kill me. Odyssey seems just as heavy.

 

[baronbeehive]

I've been in conversation with someone about this. I also realized @SonicTrance went over this with me too I think. The fact that rectifiers can impact sound quality means that the power supply is letting stuff through and not giving pure DC to the amplification circuit. Regulating the supply would cure that but then it doesn't make any sense to use a tube to do rectification. So in rather circular fashion tube rectifiers can change the sound because the circuits that use them are susceptible to changes to the rectifier lol.

I imagine you are right with your last sentence.

Re: diodes the operating speed, voltage and current must be a factor, the faster the speed the better the rectification. If it is struggling to keep up with the input to the diode before breakdown, that must affect the sound in a way. I don't think diodes are 100% efficient so this could be a factor, also when breakdown and reverse polarity occurs I think the efficiency of recovery to the correct current flow would have an effect. I don't know how that would affect sound but it could do. Obviously the better the diode switches on and off the better it will be. I have an amp, the APPJ, that has a diode upgrade which I haven't done on it, but I assume that the reason it is effective is because it is faster.

Just my twopenny worth.

 

[bcowen]

I don't have such scale. Odyssey's weight is also on the transformers. It's tilted backwards when you carry it. I had a Sansui 907mr before that weighs 31 kgs and that almost kill me. Odyssey seems just as heavy.

You were lucky. Cary 211's were 48 kgs in the shipping crate, and 39 kgs once removed. The reward? You get to do it twice 'cause they're mono amps.

 

[Isaacc7]

You were lucky. Cary 211's were 48 kgs in the shipping crate, and 39 kgs once removed. The reward? You get to do it twice 'cause they're mono amps.

Those Cary amps are beasts, but sweet ones One of my favorite features of those is the variable feedback. I usually preferred it with a little bit of feedback. I don't remember the increments but I seem to remember liking them set to 1/3 to 1/2 on the knob.

 

[Isaacc7]

I imagine you are right with your last sentence.

Re: diodes the operating speed, voltage and current must be a factor, the faster the speed the better the rectification. If it is struggling to keep up with the input to the diode before breakdown, that must affect the sound in a way. I don't think diodes are 100% efficient so this could be a factor, also when breakdown and reverse polarity occurs I think the efficiency of recovery to the correct current flow would have an effect. I don't know how that would affect sound but it could do. Obviously the better the diode switches on and off the better it will be. I have an amp, the APPJ, that has a diode upgrade which I haven't done on it, but I assume that the reason it is effective is because it is faster.

Just my twopenny worth.

What you say makes sense. Also makes me think that high speed rectifiers are the way to go. I'm certain that the engineers who designed all the classic tube amp circuits would have used solid state rectification if they had access to it. Then again, the engineering mindset abandoned tubes as soon as "better" solid state amplification came around I'm glad that I opted for solid state rectification if for no other reason I don't have to spend money on the fancy rectifiers!

 

[gibosi]

I imagine you are right with your last sentence.

Re: diodes the operating speed, voltage and current must be a factor, the faster the speed the better the rectification. If it is struggling to keep up with the input to the diode before breakdown, that must affect the sound in a way. I don't think diodes are 100% efficient so this could be a factor, also when breakdown and reverse polarity occurs I think the efficiency of recovery to the correct current flow would have an effect. I don't know how that would affect sound but it could do. Obviously the better the diode switches on and off the better it will be. I have an amp, the APPJ, that has a diode upgrade which I haven't done on it, but I assume that the reason it is effective is because it is faster.

Just my twopenny worth.

Interestingly, one of the reasons some prefer HEXFRED solid-state rectifiers is because they turn on and off more slowly, similar to a tube. They believe that very fast switching solid state rectifiers exhibit more odd-order "hash" distortion.

But given that my ears are old and worn out, I can't hear it. lol