Tube Audio

[tin ear]

I want to experience and understand tube audio enough to see if it is for me.

Alas, my budget runs in the mid-consumer range, so I am looking for good books on the subject, and kits. Can anyone point me in the right direction?

Wisdom gathered here & elsewhere tells me I should start at the front end of the audio "drive train" - a phono pre-amp - then keep working my way toward the speakers. That way I can stop any time & still gain tube sound.

My level of expertise is intermediate, I'd guess. I have built circuits from schematics using perf-board & dead-bug wiring. I could build a kit with no problem, I think. Or a project from a parts list, a schematic, and wiring diagram, but I think a kit would be safer for a first project.

TIA for any help
Jon

[Dusty Chalk]

Probably as good an introduction as any to tube audio would be a tubed headphone amplifier and a pair of headphones. Headwize has some nice diy projects.

[Feanor]

I want to experience and understand tube audio enough to see if it is for me.
...
Wisdom gathered here & elsewhere tells me I should start at the front end of the audio "drive train" - a phono pre-amp - then keep working my way toward the speakers. That way I can stop any time & still gain tube sound.
...
TIA for any help
Jon

But the only tube component I've ever used was a Behringer T1951, a "tube" equalizer. I'll tell you about that in a moment.

A lot of people feel that you will get a large measure of the tube effect putting one component that's tube any where in the chain. A tube preamp is a popular choice because (a) it benefits all sources, and (b) will not compromise bass performance to the same extent as a tube power amp.

Another option some have found helpful is something like a Musical Fidelity "tube buffer"; this can be placed between your CD and preamp, or between the preamp and power amp, or in a tape or external processor loop on the preamp. My Behringer T1951, an equalizer with a tube "buffer" built in, was placed between my pre- and power amps.

Heaven forbid that I suggest my tube experience is typical, but I found the Behringer did soften the sound, (rather than warm it), but also reduced the micro-dynamics a bit. Interestingly when the tubes burned out, (after only a thousand hours or so :( ), the equalizer still worked but a slight "grain" to the sound became noticable, so took the unit of circuit pending tube replacement. This happened about a month ago but I haven't been a rush to replace the tubes.

[JoeE SP9]

A tube preamp has been in my system since around 1981. I currently use a tube preamp and tubes to drive my ESL's. I'm even looking for a new preamp, tubed of course.
Welbourne Labs
Bottlehead
These are two good places to check for kits, parts schematics and help.:idea:

[tin ear]

I currently use ... tubes to drive my ESL's.
Which tubes? I've been on the net all day and the 300Bs are looking pretty good (except err.. in price :eek: ) I guess $180 - 275 / pair of decent tubes isn't terrible, though. Interesting link:
http://www.enjoythemusic.com/magazine/equipment/1201/300b/index.html

[Mr Peabody]

I use Conrad Johnson tube gear and moved to it from Krell, I don't want to generalize so I will just say the C-J separates had a significant increase in micro and macro dynamics over my prior solid state. I was also pleasantly pleased to hear that this gear did not have all the tube stereotypes, the highs were smooth but not rolled off, the bass was thicker and did not have the iron grip of Krell but had detail nonetheless. The Krell also offered a bigger punch in the low end. My power amp uses EL-34's, I've been told that 6550's and KT-88's have even better bass control and slam. I think 300b's are used in triode amps which are low power and require very efficient speakers. I'd recommend sticking with ultralinear design, especially if you have a budget. Good sounding efficient speakers, which I have yet to hear any, cost big money.

I started introducing tubes by using a Audio Note tube DAC. This made my presentation more natural but still no comparison to having all tubes. I also have the Musical Fidelity X-can headphone amp which has I think one tube. If the manual didn't give this info you would not know it by the sound. I still have a solid state phono stage and it sounds very good through the C-J separates.

I really disagree with those who say putting one tube in your system will give you a tube sound that's not true. Even with my Audio Note tube DAC front end, the sound changed but the Krell still maintained it's dominent sound characteristics. This may be an extreme example though because I found the slightest bit of Krell in a system changes the sound, toward their character. My theory is it's because of Krell's over the top use of high current. Further, evidence, while my power amps are being shipped off to C-J to become monoblocks I put my Krell into the power position. This is an integrated amp and I'm running the preamp into the theater bypass to use the power amp section. To my surprise, I'm not really pleased with this set up and glad it's not permanent. I don't know if it's a synergy problem or the "theater bypass" is not the same as a dedicated preamp input. The Krell/Audio note and the straight C-J both sound better than the C-J going into the Krell. Maybe there is an impedance mismatch. It's hard to put into words what I don't like about it, the sound seems to lack the air I'm used to and even less detail which is uncharacteristic of both components.

I'd say if you are going to get into tube gear you need to hear as much as possible in order to know what to expect and what tubes can do. Tube brands vary as much as solid state in sound quality and character.

[jrhymeammo]

Which tubes? I've been on the net all day and the 300Bs are looking pretty good (except err.. in price :eek: ) I guess $180 - 275 / pair of decent tubes isn't terrible, though. Interesting link:
http://www.enjoythemusic.com/magazine/equipment/1201/300b/index.html

Hi tin ear,

Some of the kits I've seen on the net uses 6N6 tubes in a pre-stage. If that's the case, you may want to avoid them. Alot of preamp tubes should last around 1,000-5,000 hours as oppose to 500-2000 on power tubes. I've heard that 300Bs last slightly longer than typical EL34s and KTs(66,88,90,100).

If you are interested in an amp that uses 300Bs, you may have to purchase different speakers than your PSBs. I believe your PSBs has sensitivity of around 90. I'm a newbie like you when it comes to tube audio, but sensitivity and other factors need to be considered. But in general, amps with 300Bs are more desireable when mated with high efficent speakers(95 dbs and up). Of course if you have a large listening room, you may want to use speakers like Heritage series by Klipsch.
Checkout the specs on this one.
http://www.klipsch.com/products/details/la-scala-ii.aspx
It has a sensitivity of 105. With speakers like that, you would only need 2 watts of power to drive as loud as your PSB at 128 watts.

My tube integrated is rated around 45 watts and my speakers are rated 87. It plays plenty loud with goodness, but sometimes I wish my speakers were rated 2-3 dbs higher.

Just somem to think about.

-JRA

[tin ear]

Does "not enough power to drive the speakers" mean the speakers won't sound good at all, or that they just won't fill a room?

I discovered nearfield listening for myself last weekend. Wow! I figured the 300Bs in push-pull might work for that, with my B15s.

Unless I have them positioned wrong, the HT surround channels don't seem to do much. The B15s seem wasted there. Was thinking I'd steal them out of the HT system & replace with something lesser. Then use the B15s like they ought to be used -- for listening, not just to fill in a little ambient sound now & again.

-j

[tin ear]

http://www.klipsch.com/products/deta...-scala-ii.aspx (http://www.klipsch.com/products/details/la-scala-ii.aspx)

Uh oh.. Big speakers again. Little out of budget too. :eek:


It has a sensitivity of 105. With speakers like that, you would only need 2 watts of power to drive as loud as your PSB at 128 watts.

IIRC that sounds right. Wow! Those could be driven louder with the 2A3s or even 45s than my HT amp could drive my PSBs at full power? Is that right? 15 db = 5 doublings in sound pressure and all, but.. ? Amazing things must happen when you spend $5500 for a pair of spkrs. :confused:

[JoeE SP9]

Which tubes? I've been on the net all day and the 300Bs are looking pretty good (except err.. in price :eek: ) I guess $180 - 275 / pair of decent tubes isn't terrible, though. Interesting link:
http://www.enjoythemusic.com/magazine/equipment/1201/300b/index.html

My equipment list shows a pair of Dyna MK-III's. They were originally 60 watt tube amps using a pair of 6550's as outputs. I have done extensive modifications to them. At present the only things they have in common with the original Dyna's is the output tubes, transformers and the chassis. I have changed the input driver boards and there is only point to point wiring. They drive my front channel ESL's from 80hz up.:cool:

[tin ear]

My equipment list shows a pair of Dyna MK-III's Oh, OK. Thanks. Sorry, I didn't know enough to recognize what those were. (This is why I need to find some good literature on tube audio.)
Just doing some minor googling I see I'll need to do some extensive googling on Dynaco / clones and the 6550 tube.

[JoeE SP9]

Unless you have very efficient speakers leave 300B's and any reasonably priced SET off your list. In general you can figure that a pair of EL34's will give around 35-40 watts and a pair of 6550's/KT88's will give around 60-70 watts. These tubes have the added benefit of being in plentiful supply and reasonably priced.:cool:

[R.S.]

You may want to consider an older Dynaco PAS 2 or 3 preamp with 12AX7 tubes. There's a lot of them on Ebay, plus you can buy new boards for them for modern modifications. There are many resources on the internet discussing modications and it's history. They are very quiet, detailed and reliable.



I want to experience and understand tube audio enough to see if it is for me.

Alas, my budget runs in the mid-consumer range, so I am looking for good books on the subject, and kits. Can anyone point me in the right direction?

Wisdom gathered here & elsewhere tells me I should start at the front end of the audio "drive train" - a phono pre-amp - then keep working my way toward the speakers. That way I can stop any time & still gain tube sound.

My level of expertise is intermediate, I'd guess. I have built circuits from schematics using perf-board & dead-bug wiring. I could build a kit with no problem, I think. Or a project from a parts list, a schematic, and wiring diagram, but I think a kit would be safer for a first project.

TIA for any help
Jon