this is kind of a thread from a previous post that got long winded with a lot of topics. (i think i started that). course it was soundhound again that got me started back up on this (it's ur fault...how'd u get out of mexico? and where's my tequila,SLL?)
anyway, yeh, the 300B! tubes! valves! question: what electronic amplifying device can one name made today that one would pick as a device that could be bought 50,60, or even 70 years from now? could you pick a specific transister or op-amp device and hope it could live that long (ie: still in manufacture) probably not, i'd venture. The 6L6 was in production over 70 years ago...and they are still crankin' 'em out!
the military (SH), when i wuz in (67-71), were still using tubed equipment. our video amplifiers for the Apollo mission (video distribution from the 'long lens tracker' to the W.Von Braun lab, and various other places) were 'RCA 45' wideband video amps. things were absolutely flat up to and past 7 meg. we set em up pre-flight and once into 'red-frames' they were not touched again from about 3 days before blast off till final splash down. MW transmission back to cape was of course tube as it still it...teeny tiny klystrons...probably upgraded now...but still either klystron or TWT tube amps. nowadays in sat transmissions there are transistor amps for this porpoise but they just don't swim as well and i know of no one who uses them without at least keeping a TWT on hand.
the 300B...ahhh, how sweet the sound. SH, i worked also for 4 years at WEco. they hadn't yet cranked the factory back up but the legend was always in the air...that we at one time made the best darn tube on the face of the earth. a few years ago after reading of its comeback..after a few ups and downs...i think i got a lump in me throat when i at last saw the new one come to life and glow! didn't even need to hear music from it's output..heard something different entirely that day!
So charlie, if u like the diy...you can pick up many tube amp diy's these days. i have an old re-built scott that uses 6550's and is 30clean watts per ch....sounds wonderful on my lil LS3a's in the bedroom. you can find these things at e-bay and electronic sites and get em for next to nothing. i also downloaded the schematics from somewhere for free...many other vavle amps for diy are available...even and esp. the 300B...warning,as SH can attest, the 300 is mucho expensive and outputs 3 to 5 watts...must have lothar's or big big klip's or others with ultra hi sensitivities. but the sound that do come out is just awesome!
ok, when is outlaw gonna tack some into a mono block?

------------------
t higg

[This message has been edited by thigg (edited February 22, 2003).]

Well, when me and mule Josie were on the way to TJ, all I needed was some back issues of Stereophile and my stock of TOOBS! The Russian company Svetlana just released a reasonably priced 300B - but you're right, a newly minted Western Electric 300B is pushing $700.00 !!! But they do last almost forever, so i'm told. I have a good stock of "jan" military tubes like 6v6 etc.

It seems that a lot of the common electronic parts that you could purchase even 10 years ago are no longer made. Have you tried to buy a polystryene capacitor lately?? Sorry, no longer made.

One thing that I miss from the current audio/HT scene is the "do it yourself" spirit. I bet you've built your share of Heathkits. That used to be common, but now most equipment is barely repairable, if at all. That's too bad, since a lot of the enjoyment of the hobby is the building aspect, and the accomplishment that comes from that. Oh well....

------------------
The Soundhound Theater

You should check out AudioAsylum. Tube DIY is alive and kicking. I recently built a 12AU7 based preamp kit from Bottlehead. It is sweet.

This is the wrong forum to talk about tubes. After all, Outlaw is all about lower cost solid state HT, not tube based stereo.

This is the wrong forum to talk about tubes. After all, Outlaw is all about lower cost solid state HT, not tube based stereo. (zacster)
sorry zac...but also this is an outlaw to outlaw BB...and heck, we keep it up and who knows...outlaw might just put in a tube output stage after the 'a' in dac.
gottta go for now folkssssssssss. cnn just blew the 430 whistle. where's my lunch bucket?

ANYPLACE is the right place for tubes

stop! i can't figure out who said we can't talk about tubes! whut's that got to do with anything? hello it's me...i've thought about you for so long....IT's a bout ze muzac. and outlaw has these sites for muzac and der stuff to help uz mit der muu-zac.
where is my tequila?

I wasn't saying you can't talk about tubes here, just that you won't get much of a response about them. Most people on this board won't know a 300b from a 12au7. I didn't until a few months ago. Probably most people looking to buy tubes at high-end stores don't know the difference either.

Tubes DO sound better. They also cost MUCH more.

"I didn't know until a few months ago. Probably most people looking to buy tubes at high-end stores don't know the difference"...zacster.!
ahhhh, but concerned one..u just answered the question of ur concern!
u; u just said I didn't until a few months ago..." but you now (know) see! you learned at a ... point in time. a year ago..by ur logic; u "would not have known".. but we waited....waited for uuu. and now ...u hear a difference; don't u?
a margaa-ree-ta please pour moi!

zacster:

Well...did you buy some tube equipment? - you didn't say. If so, what did you get? I guess I could find out by just cruising around your neighborhood and looking for the power meter that's spinning around the fastest - that'd be you!

------------------
The Soundhound Theater

"Have you tried to buy a polystryene capacitor lately?? Sorry, no longer made."

Soundhound, this place has them:

http://www.welbornelabs.com/rel.htm

In the interfaces of my Acoustat 2+2s and 1+1s, I have upgraded the capacitors on the high frequency low voltage side to include a 1.5uF polystyrene cap, a 10uF polypropylene film and foil and a 47uF metalized polypropylene. Gone is any electrolytic.

At my work, I sometimes come across small value polystyrene capacitors in the range of a few hundred pF to 4nF at 630v. They are usually in some old lab that is being cleaned up or out.

It is good that some of the old tubes are still available as "nos: new old stock" or are actually being made. When the semiconductor industry is sufficiently mature (i.e. something newer has came along and made it relatively irrelevant) the best of the last of the semiconductor devices may enjoy a popularity if enough people want them and are willing to pay for continued production of a then-to-be niche product.

My favorite tube of all time is the One-D-ten-T. Lots of them where I work.

Paul

Paul:

I recently was shocked that polystryene caps that I routinely use in my projects are no longer made. I get mine through an industrial supplier, and if anybody can get them, they can. I use mostly small value types, and have a supply of a few values in my stock. It seems that if somethng isn't used in a computer something-or-other, you can't get it. Even some simple hardware things like 3/8" shoulder washers are very hard to get now, but I used them to insulate RCA and 1/4" jacks. I'll check out your link. Thanks!

------------------
The Soundhound Theater

scuse me while i kiss the sky. i do believe i forgot why i'm here.the o-bee-ka-no - bee tube? i've been in this alonggg time but escusa-moi. i jst don't think i know that tube (he pleads egg-no-ranch, here). what kinda stage is that tube...i'd certainly like ta hear it. ah mean, ese hit a mic, line, or hi-gain dee-vice? i do love that word ...vice. and this cap thing...i think youse guys uncovered a pro-blem of mine...my last mains were jamo's...xovers had poly's...my overture duals jst fried 'em; the xovers, several times..they wux good...replacin the poly's whut blew every time i...had friends over for real wad-kaa. 3rd eye blind...1st album, cuts 11 thru 14...holy shumit! me amp never gets 'dirty' jamo's never 'compress'...they jest...blowed up...every time. (707i's)...i went back to maggies.
jest, also, today, got me virgin vinyl's in from..rhino...of the re-mastered 'last waltz'. oh me! box, i opened (the cardboead). an' thar hit wuz! haven't had the gonads to cut the cellophane round the 'real' box. i mean...i saw it live...the tour, not the ny video version w/ neal n bob n van n JONI! n that wonderful tabernakal group! i keep readin all these pages.
question,: should i fire up the 'table' 'n cut open this sweet elixer fer listenin' o'er me ...valve preprepreppre amp n make it 'neo 7.1 rat darn now?
sub-meet yore votes at internet site .vrb-555....(you guys (gals) know that's uh joke, huh...pass me a'nother jelly donut...priscilla.
hey, did u guys read bout SLL's trip this weekend?....go to the main board, or is that the 950 main board n look for the SLL 'subwoofer' post! tis truly worth it!
thigg, burns,aka...thermador k. pascal

[This message has been edited by thigg (edited February 22, 2003).]

Class "A" single ended Triodes!!

------------------
The Soundhound Theater

Oh, I get it…it’s a ‘SET’ thing to do. The jamo’s I blew up 3 times. 2nd time…the mids completely dissipated from the spyder’s…and the smell o those styrenes..whoo. jamo replaced it all..both times. The 3rd time I did it myself. Went to a little place that specializes in DIY projects (mostly speakers). They carried the styrenes but they were for car systems. Darn things were HUGE. Wouldn’t fit the xover boards…so I bought…gulp..lectrets. then I sold em. To a friend..he didn’t mind…heck he was the guy who was listening when they fried. I think later he replaced the caps having found some somewhere. They are very good speaker’s…he’s got em, I think in his 2 channel room..pushed by a beautiful 60w stereo-valve Jolida integrated. Me…I went back to maggies…is very hard to blow a 1.6…and the ribbons are fused. I shoulda fused the jamos but just never got a round tuit.
has anyone seen SLL...hope her ol man's ok.

my scott valve in the bedroom just recently blew the rectifier tube...gotta go all the way into atlanta to ACK Radio for a replacement...darn thing was only a year or two old. had to put in the little crown 75 for now...actually works really well with the rodgers and my lil bity jamo surrounds.
they are so cute. gonna toss out the 4inch paper drivers they use opposite the other 4inch mid-woofers. they can really compress and pop on movies and long hair music. my lil davids are much better but i lost a tweeter beyond repair (they r very old..but kick serious butt for a 4 inch...and the driver plate is a real hard unit to find without driving to germany. anyone know where i can get tweeters for visoniks? they ain't in this neck o the woods. guess i could google for a site, huh!

Soundhound,

Yes, I bought a Bottlehead Foreplay preamp. Built it myself. I've already done a few mods on it. Runs off of 2 12AU7 type tubes. Right now, its on the bench with a loose connection somewhere. Whenever someone jumps (3 kids) in my old house I get a popping noise. Working on this stuff is a blast.

Next project will be a push-pull EL34 amp, like the old Dynacos.

oh me! i can't even remember the amp's name in my bedroom..it's not a scott..it's the dynaco ST-70. (and you call yourself an engineer,thigg?!) scott, dyna, whatever.
EL-34's are wonderful glowing things!
now is my bike a harley or an indian...better go check. it's a chilly but beautiful riding day.

------------------
t higg

Sorry to veer off topic, but when I see a post from a fellow Acoustat owner I just have to jump in. I'm curious, do you have 2+2's and 1+1's in the same system? What do you use for center channel? As for myself, I've got 2+2's on the front and a stack o'panels in the basement waiting deployment in a full electrostatic surround configuration. I'd appreciate hearing your thoughts about setting up a system like this. BTW, I drive the acoustats with a pair of Servo-Charge (tube) amps so I guess maybe I'm not off topic after all!




------------------
Tekdredger

Tekdredger,

My 2+2s and 1+1s are all in the same system.

The 2+2s are up front and the 1+1s are the rear surrounds. I do not have a center channel speaker yet.

In regards to the center channel, I did buy, on e-bay, an Acoustat electrostatic panel (a bare, single panel) with the idea of having it as a spare in case any damage occurs to one of the 2+2s or 1+1s. I am also toying with the idea of using it as a center channel speaker if I can also find the HV stepup audio transformers for it.

The motivation for using the 1+1s as surrounds was the purchase of a sacd player. Prior to the sacd player, the surrounds (Bose 301s that I got for really cheap) were used only for DVD movie sound effects: explosions, gunshots, aircraft sounds and other NOISES that the bose did an acceptable job on. Music is a different story, so I decided to use the 1+1s as the surrounds.

I don't have much in the way of multichannel sacds yet, so the 1+1s still just make movie noises, like the bose, but they are much more musical movie noises.

Paul

------------------
the 1derful1

but they are much more musical movie noises.

I know that feeling.

Paul,
Sounds like you and I are on the same page. I just got a pioneer DV-47Ai for multichannel hi-rez music. I'm currently lusting after a 950 to bring it all together which is why I've been lurking in these forums lately (that undefeatable bass summing on the 5.1 direct input really has me bummed though). I've never used a center channel either. The 2+2s fire down the long axis of the room and they image so well I've never felt shortchanged. Nonetheless, I'd still like to try a single panel on top of my RPTV. After I got the tube amps that freed up the interface modules from the 2+2s to use with the other panels I got. Have yet to hook any up yet though...I'm still working on some ideas for frames, grill cloths, etc. How do you have the 1+1s oriented for rear channels? Are they on the sides aiming fore and aft to yield a dipole pattern or do you have them more behind you and aiming at the listener? Lots of room for experimentation here! I would like to mount single panels to a pole (like a pole lamp) that would let me rotate or move them around the room easily. Being able to rotate the pole to control the radiation pattern might be useful when switching between movies and music.
I hope you find some transformers but don't rule out HV tube amps if you can swing it...they are worth it!
Happy Listening/Viewing!


------------------
Tekdredger

Tekdredger,

I have the 1+1s aimed towards the listener (for music use) but for movie soundtracks, I would consider experimenting with having them face fore and aft.

I don't feel a pressing need for a center channel speaker but I am keeping the ideal alive in my mind.

I am toying with the idea of making a mosfet output stage power amp for the center channel. At work, I was asked to make a high voltage pulser (for piezo transducer use) with adjustable pulse height, adjustable rise and fall times, etc. I gave them a linear amplifier that accepts input from a pulse generator. They make the desired pulse adjustments to the pulse generator and the amp I made for them gives them a bigger (by a factor of 100) version of the input. The pulse amp output is from 0 to 500v.

I was thinking of perhaps making a version that had output from -250v to +250v and with more current output capability (a few 100s of milliamps or so) and getting interface transformers with a much lower turns ratio than what is the usual (50 to 150) for electrostatic speaker use. If I made a version of the amp that had differential output (so that I had +/- 500v available to the speakers, I may even see how much acoustic volume the Acoustat panel would put out with no interface transformers. Any equalization that would need to be done for the Acoustat panel (performed at the low voltage side of the interfaces) would have to be done at the input to the high voltage amp.

The mind boggles at the possibilities.

Or, in my case, the mind boggles.

Paul

------------------
the 1derful1

[This message has been edited by Paul J. Stiles (edited March 02, 2003).]

Paul,
Your amp idea is close to an idea I was toying with a while back. Since direct drive amps are somewhat rare and expensive, I thought why not use a conventional push-pull tube amp and hook up the output transformer backwards. In other words, transform to a higher impedance load instead of a lower one. I never got out the calculator to see if the turns ratios would work out but my gut tells me it would be in the right neighborhood. Voltage rating on the windings would be an important consideration though. I seem to remember Plitron coming out with some toroidal designs intended for use with electrostatic speakers. I would have to research that one some more but one of their wide-band models might make a good choice to mate with your mosfet design.

Good Luck in your audio pursuits!

------------------
Tekdredger

Soundhound,

Some reasonably priced polystyrene capacitors (non-audio jewelry prices) at Mouser electronics. Only rated for 50 volts though.

http://www.mouser.com/index.cfm?handler=...Number&x=15&y=9

Paul

------------------
the 1derful1

Paul:

Thanks for the link! I've bought from them before, but didn't know they had polystryenes. That's great to know, since I won't use any other type in my filter designs.