Full Range Amplification - A Revelation

[DaveCan]

In the guitar amp world Vox AC30, Marshall Plexi etc, yummy! And most guitar guys love tube amps so that should say a bit right there about tubes and sound, at least for that application..

All I've ever had for a home stereo since I got into a tube amp some years ago now, was typical integrated SS amps with the last being a HT Receiver by Yamaha..

I've had lots of comments from people and women too from just noticing the background music playing, and asking what it is or commenting that it sounds nice, never really remember that before with my SS stuff so much.. Mostly what I notice, and think others notice too, is as the time goes by while the music is playing, is that it just never seems to get fatiguing at all.. I can play anything from older Jazz, Blues, to Pop, Reggae and even some heavy stuff and it just all seems to sound better than any other system I had before etc.. Tubes and synergy seems to be pretty magical when it all comes together.. Never heard a highly regarded SS amp before other than some Carver, Bryston, Sugden, and Linn stuff, so not saying tubes are better than SS just that I'm liking what I have, so can relate to the OP post etc..

[cogitech]

On another note, how many of you are aware just how ridiculous the prices for amps can be?

I just saw this and the only reaction I could manage was outright laughter!

HigherFi AMPS - Worlds Best Hi-Fi Audio Amplifiers

But what do I know?

Maybe the "NEW AUDIO FRONTIERS 845 Special Edition Stereo" 25 wpc tube amp actually does sound 20 times better than my Shuguang.

One thing is for certain; I'll never know, or care

[Bob Richards]

Originally Posted by cogitech

Thanks very much for the info. I love learning about this stuff!

If I ever get the courage to replace those caps, which caps would you recommend I use? Auricaps? Solen? Also, I am not a skilled solderer, so I am not so comfortable removing the capacitor leads from the board. Would it be practical to snip the existing caps off, leaving the leads in place, and then solder the new capacitors' leads to the old leads? Silly, I know, but would it be a disaster?

WRT tube rolling; I have already ordered a matched quad of EH EL34 and a matched pair each of NOS-tested Sylvania 12AX7 and NOS RCA 12AU7. I will wait till I have about 150 hours on the amp before doing any rolling.

I'm a bit of a skeptic on cap changing. If it has polyprop caps I wouldn't mess with it. Probably any Polyprops are fine. Personally I think the expensive ones are for fools. I'm quite happy with Solen brand.

Any caps have more distortion when they are operated in their rolloff region; where the cap has significant resistance in the circuit. Putting in a bigger value would reduce that if it was that simple, but the caps that drive the output stage in most topologies are responsible for increasing the crossover distortion in the push-pull output stage, and the bigger they are the worse that gets, so you're kind of stuck on that. At Tektronix we had a saying; "If it ain't broke, don't fix it". I think that applies here. Speaker placement and room acoustics will make orders of magnitude more difference. Mess with that instead.

[Bob Richards]

Originally Posted by cogitech

Great! Thanks again.

Re: Psvane tubes; I am very hesitant. The price is very, very high, and while I am very impressed with this amp, GF does also sell some products which I would put into the category of "snake oil" ($100 power cords, $500 interconnects, etc.).

Maybe the Psvane tubes are amazing, but I am not sure I will hear $300 worth of difference. Recall what I paid for the amp!

A close friend of mine (Matt Kamna) is into tubes more than about anybody on the planet. He has well over 10,000 tubes, a huge state of the art lab, has improved the worlds best tube tester, built countless tube amps, etc., and from hearing about his experiences I get the impression that there is likely more difference between two tubes of the same brand and type, than between two tubes of different brands. Even some of the better brands (JJ) have QC problems. It's all hit and miss to a significant extent. So to pay god awful amounts for vintage or "special" tubes seems foolish to me.

On caps, polyprops with foil rather than film might be better for the high voltage swings. The silver/oil caps are very probably snake oil, along with expensive interconnects and speaker wire. It's the connectors that are likely a weak link, not the wire itself. Connectors should have the gold alloy coating and be soldered to the wires. Any more than that is money down the toilet.

[cogitech]

Originally Posted by Bob Richards

I'm a bit of a skeptic on cap changing. If it has polyprop caps I wouldn't mess with it. Probably any Polyprops are fine. Personally I think the expensive ones are for fools. I'm quite happy with Solen brand.

Any caps have more distortion when they are operated in their rolloff region; where the cap has significant resistance in the circuit. Putting in a bigger value would reduce that if it was that simple, but the caps that drive the output stage in most topologies are responsible for increasing the crossover distortion in the push-pull output stage, and the bigger they are the worse that gets, so you're kind of stuck on that. At Tektronix we had a saying; "If it ain't broke, don't fix it". I think that applies here. Speaker placement and room acoustics will make orders of magnitude more difference. Mess with that instead.

I appreciate your perspective, Bob. You sound like a common-sense kind of guy, you you obviously have a ton of experience.

Unfortunately for me, I am a "if it ain't broke, I ain't fixed it yet" kinda guy. I can never just leave well enough alone. Regarding re-capping, I have seen many threads here where people have reported great results by upgrading caps, particularly in sub-standard Chinese "junk". This amp isn't sub-standard Chinese junk, but corners must have been cut somewhere to hit this price point, right? Anyway, I am not married to the idea of cap-swapping, but I think it would be a good learning experience for me and I think there might be some benefit, particularly if I can determine with some certainty that the existing caps are low quality.

[Fast Eddie D]

Originally Posted by cogitech

HigherFi AMPS - Worlds Best Hi-Fi Audio Amplifiers

Ridiculous. Who coughs up 6 figures for an amplifier?

I'm going to build some stuff and list it there. One of a kind! Binder posts made of unobtanium! GET IT NOW BEFORE IT'S GONE! A steal at only $795,000!

[cotdt]

Bob, I think if you replace those Solens, you might change your mind about the effects of caps. I'm a measurement guy, and I actually never measured any difference when changing caps, but the sound change is so obvious, I'm going with my ears on this one.

[cotdt]

I don't think anyone actually buys those $1 million amplifiers. And anyone who does, will still have more leftover money than you or I.

[cogitech]

Originally Posted by Bob Richards

A close friend of mine (Matt Kamna) is into tubes more than about anybody on the planet. He has well over 10,000 tubes, a huge state of the art lab, has improved the worlds best tube tester, built countless tube amps, etc., and from hearing about his experiences I get the impression that there is likely more difference between two tubes of the same brand and type, than between two tubes of different brands. Even some of the better brands (JJ) have QC problems. It's all hit and miss to a significant extent. So to pay god awful amounts for vintage or "special" tubes seems foolish to me.

On caps, polyprops with foil rather than film might be better for the high voltage swings. The silver/oil caps are very probably snake oil, along with expensive interconnects and speaker wire. It's the connectors that are likely a weak link, not the wire itself. Connectors should have the gold alloy coating and be soldered to the wires. Any more than that is money down the toilet.

Matt sounds like a truly dedicated tube guy! Wow! You are lucky to know him!

When you talk about the differences between tubes, however, are you talking about technical differences, or the sound of the tubes? Technical differences, what Matt has spent a lifetime testing, cannot be argued. They are empirical data. But how much does Matt say about the subjective evaluation of tubes?

The reason I ask is because I do feel I can tell the difference between some tubes. I have rolled about 5 different kinds of tubes through my Grant Fidelity B-283 Tube Buffer (no longer in my system after installing the I-25), and there were noticeable differences. So much so that I ended up settling on a favourite - NOS Mullard 4010 - and gave the rest away to a fellow forum member (although I did keep a pair of NOS Sylvania 6AK5, since there is something very nice about them, too.)

Maybe I won't be able to tell the difference between Electro Harmonix EL34 and the Shuguang EL34. Maybe I will. Either way it is a win-win, because I will need more tubes eventually anyway and in the meantime I get to find out if I can hear the difference.

Regarding interconnects; we're on the same page. Not dollar store specials, not the $500 jobbies. Just something decent. Last time I needed an interconnect, I dug through one of my "parts n' wires" boxes and ended up finding a nice quality RGB component video interconnect. It sounds great, but I wonder if I should have used the green and blue, rather than the green and red

[cogitech]

Originally Posted by Fast Eddie D

Ridiculous. Who coughs up 6 figures for an amplifier?

I'm going to build some stuff and list it there. One of a kind! Binder posts made of unobtanium! GET IT NOW BEFORE IT'S GONE! A steal at only $795,000!

Someone will buy it.