A good article about the human ear and tubes (1 Viewer)

[Chu Gai]

Well hell, I thought I tried that earlier!

 

[Tom Grooms]

I Have Respect for Beer (Russell Crowe, A Beautiful Mind)

 

[Yogi]

Ok Chu the toast is on you.

Cheers.

 

[Scott_N]

Yogi

Did you order the 6CA7's yet? I think the only thing going for them is more bass. Changing the 6SN7's and 12AX7's gave me a little more detail without degrading the midrange.

 

[Yogi]

Scott, I ordered the EH EL34's not the big bottle and they seem to have a sweet midrange and sufficient bass. The SEDs are better overall with a good bass. The big-bottle's will be the next on my list. Also I have substituted the Sovtek 12AX7LPS for the stock tubes but haven't played with the driver tubes (6SN7s). Which 6SN7's do you have on your amp and how do they compare to the stock ones?

Thanks,

 

[Scott_N]

Yogi

I replaced the stock Sovteks with EH 6SN7's and I thought they offered better detail. I just bought some Sylvania 6SN7GTB 60'sNOS this weekend and they are even better than the EH's. The highs have more extension and the bass a tad firmer. If you try the Sylvania 6SN7 make sure it's 50's or 60's NOS not 70's. I think the Ei 6SN7's are only good for rock.

 

[Lee Scoggins]

I replaced the stock Sovteks with EH 6SN7's and I thought they offered better detail.

Audio Research has been offering Electro Harmonix upgrades. My buddies there tell me they think these are among the best tubes.

My VT100 has SovTeks (6550 times eight) and Philips tubes. I'm happy with the sound.

 

[Michael R Price]

"My point is that the sound commonly attributed to tubes isn't due to the tubes at all, but rather the amplifiers's design, and that design could have been implemented nearly the same with solid state devices."

I have a solid state amp like that! It sounds really good, once you get past the distortion.

Does anyone know why the sound of my (other, more typical) amp changed with different bias currents? After all, I didn't change the frequency response or output impedance... just the distortion spectra (probably still totalling less than 0.1%). What's up with that?

 

[Chu Gai]

Seems to me Mike that you need to get some tools like 'scopes and whatever else is necessary in order to properly characterize your experiments. In ways what you're doing is akin to trying to set the timing of a car without a timing light.

 

[Scott_N]

Lee

You should try the Svetlana 6550C which CJ uses in the Premier 140 and MV60SE. The 6550C or the GE 6550A would be my choices if my amp used 6550's.

 

[Michael R Price]

Chu,

Right... and I'd need more than an oscilloscope to measure the differences at this point! I've seen a good way to look at a distortion waveform by cancelling out the original signal, but I lost the link. It's mildly complicated, though.

 

[Lee Scoggins]

You should try the Svetlana 6550C which CJ uses in the Premier 140 and MV60SE. The 6550C or the GE 6550A would be my choices if my amp used 6550's.

Scott,

I will have to look into this tube and see what they offer.

 

[Scott_N]

Lee

The Soundstage article about the CJ amps will be in Oct. I talked to the writer this past weekend. The 6550C is supposed to have a nicer midrange compared to the Sovtek and EH 6550, but the the Sovtek and EH have more sparkle on top.

 

[Lee Scoggins]

The Soundstage article about the CJ amps will be in Oct. I talked to the writer this past weekend. The 6550C is supposed to have a nicer midrange compared to the Sovtek and EH 6550, but the the Sovtek and EH have more sparkle on top.

Thanks Scott,

I will look for the October edition. Nicer midrange is a real good way to get my attention. I will have to look into this in more detail. Thanks for the heads up.

 

[Michael R Price]

Do we hear more about different types of tubes as compared to different kinds of transistors because those differences are easier to notice because of the design used in tube amps? Or is it just because it's a pain to change out transistors?

 

[Yogi]

Michael, I think its because there are many varieties of tubes than there are types of transistors. Each type of tube comes with its own design and many designs support more than one type of output tube. Lots of combinations with tubes compared to transistors.

 

[Chu Gai]

you'll find whole catalogs in tiny print for something as 'simple' as an op-amp. the same holds true for various other transistorized components.

 

[Michael R Price]

Haha, you may be unfamiliar with the variety of transistors and other solid state active components available. I could have picked any of about 50 (maybe more) different kinds of Mosfets for my output devices. Never mind small signal transistors (there are thousands of varieties) and chips.

Maybe it's because all these solid state components have measurable specifications that do affect signal quality to some extent? I know tubes do too, but no one seems to worry about them... would take all the fun out of it, wouldn't it?

 

[Yogi]

Then maybe Mike its because tubes are easy to swap or maybe its the design, but who cares as long as tubes sound the way they do .... er...um the way they distort sound.

While we are talking about designs, it reminds me that my next tube adventure would be SET design; the simplest of all amp designs. Cant wait to hear one in my system.

 

[Scott_N]

Yogi

If you go SET then get a amp with either 845 or 300B output tubes. The Cary 300SEI with Western Electric 300B's had the nicest midrange i've ever heard and the headphone output was best i've heard.