[tlcocks]

I didn't finish my thought... So, my thought is around tube rolling in SET amps. Does it make a huge difference versus an OTL? I don't own an OTL so I can't speak to that, but I wonder. Because I hear way bigger differences with tube rolling on my ECAF than I ever did on the HP8. I heard differences, but not so big that I felt sonically it was changing the amp. More flavor. Like the difference between which red wine I use when I braise shortribs. Both delicious and tender, just a different flavor on my palate.

How much difference does the transformer make to the sound? All the designers of SET amps I've talked to tell me the transformer and caps are 90% plus of the sound of an SET amp. I have no answers, only questions. Hoping to spark some thoughts from others on this topic.

I love the food analogy, my chefly friend!

 

[Pharmaboy]

Does it make a huge difference versus an OTL?

It certainly did with my humble but fine-sounding Woo WA3. Major changes in the sound happened, first by getting a Tung Sol 5998 as the power tube; then by getting a pair of Brimar/Footscray CV455s for the input pair. I've also experimented with another Mullard input tube, CV4033s (1957). Before these changes the WA3 sounded smooth & nice, but just didn't do much sonically. With these NOS tubes, the amp is transformed.

Woo tube amps have a reputation of being dependent on NOS tubes to get anywhere sonically. The WA3 is the only Woo amp I've spent real time with, and it absolutely adheres to that reputation.

 

[jonathan c]

• Since @geoffalter11 raises the subject of rectification (conversion of AC to DC, not an orifice examination ), I will chime in.
• Owning and comparing HP8 Signature to Woo Audio WA6 (Gen 1) is a pleasure and is instructive.
• The WA6 can be fitted to use a Ken-Rad VT-231 pair via beautiful (!) Woo Audio 6SN7 => 6DE7 adapters. WA6 rectifier tube in use is Brimar CV1863. Meanwhile, HP8 runs with Ken-Rad VT-231 pair plus Telefunken ECC801S (a 12AT7-type).
• Overall, HP8 bass runs deeper, total FR spectrum has rather more control, slightly quicker transients. Imaging is more specific with HP8 - not hugely so.
• When I replace, in WA6, the CV1863 with a Mullard NOS GZ-34 (copper lined) rectifier tube, WA6 'stands at attention'. The tortoise becomes the hare, so to speak.
• The point is that WA6 attack / sound can change dramatically with a rectifier tube change. Fun in itself!
• HP8 with its diode rectification does not offer this particular wrinkle. That's fine with me. HP8 is my favourite h/p/a - of any topology .

 

[ardbeg1975]

• Since @geoffalter11 raises the subject of rectification (conversion of AC to DC, not an orifice examination ), I will chime in.
• Owning and comparing HP8 Signature to Woo Audio WA6 (Gen 1) is a pleasure and is instructive.
• The WA6 can be fitted to use a Ken-Rad VT-231 pair via beautiful (!) Woo Audio 6SN7 => 6DE7 adapters. WA6 rectifier tube in use is Brimar CV1863. Meanwhile, HP8 runs with Ken-Rad VT-231 pair plus Telefunken ECC801S (a 12AT7-type).
• Overall, HP8 bass runs deeper, total FR spectrum has rather more control, slightly quicker transients. Imaging is more specific with HP8 - not hugely so.
• When I replace, in WA6, the CV1863 with a Mullard NOS GZ-34 (copper lined) rectifier tube, WA6 'stands at attention'. The tortoise becomes the hare, so to speak.
• The point is that WA6 attack / sound can change dramatically with a rectifier tube change. Fun in itself!
• HP8 with its diode rectification does not offer this particular wrinkle. That's fine with me. HP8 is my favourite h/p/a - of any topology .

Give me tube rectification or give me a different tube amp.

 

[ardbeg1975]

Speaking of a different tube amp, my Icon 205D arrives next week when I am (sadly?) on vacation so impressions will not ensue until the first part of April. That said, interest in this thread in the 205D? or should I create a new thread?

 

[jonathan c]

Give me tube rectification or give me a different tube amp.

Is that on your licence plate ?

 

[Pharmaboy]

The tortoise becomes the hare, so to speak.

Pleasing turn of phrase. Viva la HP8.

Speaking of a different tube amp, my Icon 205D arrives next week when I am (sadly?) on vacation so impressions will not ensue until the first part of April. That said, interest in this thread in the 205D? or should I create a new thread?

Probably a new thread, simply to avoid confusion. I know of at least two people here who are very interested in any sound impressions you care to make regarding the Icon Audio 250D. That's quite an amp!

 

[jonathan c]

Speaking of a different tube amp, my Icon 205D arrives next week when I am (sadly?) on vacation so impressions will not ensue until the first part of April. That said, interest in this thread in the 205D? or should I create a new thread?

New thread .

 

[ardbeg1975]

New thread .

https://www.head-fi.org/threads/icon-audio-hp205d.972137/

 

[geoffalter11]

I like it all on this thread, personally. Maybe this is the Icon thread. I am willing to bet that Lawson will be the only head-fi member with an Icon 205D. I hope to buy one soon, but lots has to fall into place for that to happen. I want that amp.

As for @jonathan c comments on rectifiers, and not the proctologist type, I have found that I prefer tube amps with rectifier tubes. Especially in a separate power supply. I love the HP8, and it is an amp that deserves every accolade it has won. David Shaw doesn't use a 205D, he uses an HP8. Even though he knows the 205D is the better amp. There is just something about the way that amp sounds that is special. I miss it daily.

 

[Pharmaboy]

I like it all on this thread, personally. Maybe this is the Icon thread. I am willing to bet that Lawson will be the only head-fi member with an Icon 205D. I hope to buy one soon, but lots has to fall into place for that to happen. I want that amp.

As for @jonathan c comments on rectifiers, and not the proctologist type, I have found that I prefer tube amps with rectifier tubes. Especially in a separate power supply. I love the HP8, and it is an amp that deserves every accolade it has won. David Shaw doesn't use a 205D, he uses an HP8. Even though he knows the 205D is the better amp. There is just something about the way that amp sounds that is special. I miss it daily.

I listened to my HP8 on the Verite Open tonight. The input tube is that amazing Fisher 12AX7. The DAC is the Metrum Onyx, which outputs 2.5v into the HP8, 20% lower than the 3.0v from the Orchid in the other system here. That really did the trick; it all came together in the sound, which was crazy good. I went from blues to funk to choral/liturgical music to violin concerti, and every genre sounded spectacular.

When I picked up this "gently used" HP8, I had no idea what a transformative effect it would have in my audio systems. It would be absolutely unthinkable for me to do without this amp. The HP8 and the V281 are my TC-tube and SS "desert island amps," respectively.

 

[geoffalter11]

I listened to my HP8 on the Verite Open tonight. The input tube is that amazing Fisher 12AX7. The DAC is the Metrum Onyx, which outputs 2.5v into the HP8, 20% lower than the 3.0v from the Orchid in the other system here. That really did the trick; it all came together in the sound, which was crazy good. I went from blues to funk to choral/liturgical music to violin concerti, and every genre sounded spectacular.

When I picked up this "gently used" HP8, I had no idea what a transformative effect it would have in my audio systems. It would be absolutely unthinkable for me to do without this amp. The HP8 and the V281 are my TC-tube and SS "desert island amps," respectively.

Those are great amps for a "desert island". I can't disagree with either. Listening to the AC on the Aficionado and the sound is just so fast and resolving. It doesn't have the bass of the HP8, I have yet to hear an amp that does. I think all of David's amps are bass monsters. I think he likes bass.

But, what I miss most about the HP8 is the midrange, that just floated through my ears like a warm summer breeze. The HP8 is truly special. If I can't swing the 205D, I will get the HP8 again. That would be an easy decision.

 

[geoffalter11]

• Since @geoffalter11 raises the subject of rectification (conversion of AC to DC, not an orifice examination ), I will chime in.
• Owning and comparing HP8 Signature to Woo Audio WA6 (Gen 1) is a pleasure and is instructive.
• The WA6 can be fitted to use a Ken-Rad VT-231 pair via beautiful (!) Woo Audio 6SN7 => 6DE7 adapters. WA6 rectifier tube in use is Brimar CV1863. Meanwhile, HP8 runs with Ken-Rad VT-231 pair plus Telefunken ECC801S (a 12AT7-type).
• Overall, HP8 bass runs deeper, total FR spectrum has rather more control, slightly quicker transients. Imaging is more specific with HP8 - not hugely so.
• When I replace, in WA6, the CV1863 with a Mullard NOS GZ-34 (copper lined) rectifier tube, WA6 'stands at attention'. The tortoise becomes the hare, so to speak.
• The point is that WA6 attack / sound can change dramatically with a rectifier tube change. Fun in itself!
• HP8 with its diode rectification does not offer this particular wrinkle. That's fine with me. HP8 is my favourite h/p/a - of any topology .

Did you ever see the Rodney Dangerfield bit about proctologists? He meets a man and a son at one of his shows. The dad says he's a proctologist. The son says he's a proctologist. So Rodney looks at the Dad and asks him when he dies if he is gonna leave all of his a-holes to his son. haha....

 

[The Jester]

I listened to my HP8 on the Verite Open tonight. The input tube is that amazing Fisher 12AX7. The DAC is the Metrum Onyx, which outputs 2.5v into the HP8, 20% lower than the 3.0v from the Orchid in the other system here. That really did the trick; it all came together in the sound, which was crazy good. I went from blues to funk to choral/liturgical music to violin concerti, and every genre sounded spectacular.

When I picked up this "gently used" HP8, I had no idea what a transformative effect it would have in my audio systems. It would be absolutely unthinkable for me to do without this amp. The HP8 and the V281 are my TC-tube and SS "desert island amps," respectively.

Similar opinion with input voltages here to …. Set my Chord DAC to 1V output as it drives both the HP8 and CJ valve preamp with great results …

 

[lauthoerer]

Sorry, noob question: you can set the output current (?) that goes through the RCAs? Would that mean that I should set the output „volume“ of my DAC/pre-amp (see below) as low as possible to dial up the HP8 more? Or is that sth different?

Been toying with the ratio of output volume to my amps, so that I can dial them to around 12h, but kinda feel like I get worse results if I go below 30 on the DAC-9 than staying at 10h-ish on the HP8… Can’t be entirely sure yet, though…