Kevin:

To answer your questions:

I certainly do _not_ advocate using tube amps in a home theater (or stereo) unless one is willing and able to spend the necessary money, has _compatible_ components, and willing to take the time necessary to maintain them. They are certainly not for everybody. I have a long background in electronic design, specifically dealing with sound equipment, so I have the ability to get the requsite performance from them. I have deeply modified all my tube gear - nothing is 'stock'.


The tube replacement interval is about every 5 years for power tubes (much longer in a couple of my power amps) and 10 or more years for low-level tubes. Adjusted for inflation, the tubes themselves are as cheap or cheaper than they were in the 1950s. A good 6L6 output tube can be had for $15. Having regulated power supplies for the filaments is one crucial thing that must be done to get the maximum life.

You may be adverse to distortion in your equipment, but don't make the mistake of focusing on that one parameter too much at the expense of looking at other things that can contaminate an audio signal as much, or more so! The one people seem to overlook, which is vital, is room dimentions and acoustics, for one.

Dobeman:

Yeah, it's best to put your flak jacket on when entering here, at least tonight

The Van-Alstine mod is at least still marketed, although I guess there's no way to know whether or not they're still provisioning customers. Here is the link to the mod:

http://www.avahifi.com/root/equipment/amplifier/super70i_rebuild.htm

They claim to keep the good stuff and pretty much completely redo the guts, using different tubes even. The cost is fairly reasonable and it has several good reviews.

Chalie:

Looked at the link - I guess they still are available, I just hadn't heard from them for a long time. The input tubes they are using is the usual one for a lot of ST-70 mods. It is a combination pentode/triode that is an input gain and phase splitter in one tube, as was the original. The new one is better however. I actually hoarded a load of the original 7199 tubes before they bacame impossible to get - maybe I should sell them on eBay

Interesting Reading about tube amps

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MeanGene's Home

[This message has been edited by MeanGene (edited January 14, 2003).]

Well, gots to admit I learned something new today.

Something else to look into, and maybe at least someday try to compare to what I have now... (Part of me says "dang", and part of me says "cool...")


For kicks:

http://ubb.outlawaudio.com/ubb/Forum6/HTML/000190.html


[This message has been edited by Kevin C Brown (edited January 14, 2003).]

How in the Hell did you guys get so off track here?!?

____________________________________________

we basically all know that the 1066, though a good unit for the money, costs 40% more, has no tuner, has less warranty that's backed by weaker consumer-service...through a dealer, has double bass (a bad thing) and well...isn't made by outlaws for outlaws.

a pitcher of margaritas makes an outlaw rowdy, and who can resist razzin' soundhound about his glowing closet????

SH: you need more than 10 watts, good or otherwise, to allow for transients in that monster rig of yours, and i'll guarantee you have it too! BTW, what's it gonna take to get you to listen to dvd-a/sacd??

tape--->tubes--->more tubes--->speakers
VS.
high-res digital--->digital--->class d---> speakers

heavyweight title bout coming soon...place your bets...

That was a good joust, entertaining and enlighting.

Things must have gotten a bit rowdy here last night, since my internet connection was fried today, and I just got it back. Well, as they say, if noth'in gets broke, 'ya ain't having a good party.

Bosso:

I wasn't kidding about the 10 watts! With 106db for one watt efficiency, you can see that I am just crusin' at even 100 or more db SPL. The amp (tube, of course) that runs the woofers on my main speakers can put out 60 watts, and they must reproduce only down to 60Hz. You can see that it doesn't take much power with that much efficiency. The subs are a different story though - I use all of those 1000 watts sometimes when reproducing bass down in the range of 20Hz or below. Even the subwofers are pretty efficient however as such speakers go. Each side has two 8 cubic foot enclosures and the subs are in a 3/4 space acoustically (i.e., a corner) , so there is a lot of room gain. Also, there's a great deal of mutual coupling between the two woofers on each side, and between the left side and right side of the room on deep bass. I'm probably getting a total of 12db or so more signal from room gain and mutual coupling.

I'm waiting on SACD / DVD-A until I can get a universal player that is a couple generations more along the obsolence path. I've gotta be truthful too, that I find it a bit weird the way some popular music albums are being mixed/re-mixed. I just can't get used to important instruments coming from my side or behind me - it activates my 'fight or flight' animal instincts, and distracts me from the overall message of the music. Maybe I'm just too steeped in the traditional 'performance model' of having performers in front of me. Maybe I'll get over it with time. One interesting bit of trivia - when quadraphonic (yes, I was alive then) was being introduced in the early 1970s, one of the big classical demos was Berlioz's Requiem which was originally arranged to four brass choirs in the four corners of the church. You couldn't go to a demo room without hearing it.

In the meantime, I hear a lot of surround music in my work, and mix and edit a good deal too (mostly orchestral scores).

[This message has been edited by soundhound (edited January 14, 2003).]