[bcowen]

Yikes! Please be sure your amp is up to the task posed by VR-102's. Please see http://www.r-type.org/exhib/aaa0300.htm (at the bottom of the page). A VR-102 draws a heater current of 1.3A, literally more than double the 0.6A of a 6SN7. People around here quite correctly warn each other about rolling in an ECC32, with its 0.9A draw. A VR-102 is much worse than that!

Since he built the amp, I'm pretty confident he knows what he's doing.

With tubes and amps, I mean. As far as some other stuff, well, that's different.

 

[JKDJedi]

Since he built the amp, I'm pretty confident he knows what he's doing.

With tubes and amps, I mean. As far as some other stuff, well, that's different.

this

 

[Paladin79]

Yikes! Please be sure your amp is up to the task posed by VR-102's. Please see http://www.r-type.org/exhib/aaa0300.htm (at the bottom of the page). A VR-102 draws a heater current of 1.3A, literally more than double the 0.6A of a 6SN7. People around here quite correctly warn each other about rolling in an ECC32, with its 0.9A draw. A VR-102 is much worse than that!

I designed my amp and have a pretty good understanding of the heater current limits. 1.3 amps plus 2.4-2.5 amps are still within said limits. I am also in the unusual situation that if I ever damaged it, I probably only have enough parts to build ten more unless I had to buy more transformers.

Your warning is great for those who might not know their amps capabilities. I gifted one to @bcowen knowing full well he might try some strange tubes but if he destroys the filament windings in the power transformer, he then owns a 2 lb door stop.

Oops I was answering while others were answering as well. Somehow Mr. Cowen was channeling my response.

 

[bcowen]

I designed my amp and have a pretty good understanding of the heater current limits. 1.3 amps plus 2.4-2.5 amps are still within said limits. I am also in the unusual situation that if I ever damaged it, I probably only have enough parts to build ten more unless I had to buy more transformers.

Your warning is great for those who might not know their amps capabilities. I gifted one to @bcowen knowing full well he might try some strange tubes but if he destroys the filament windings in the power transformer, he then owns a 2 lb door stop.

Oops I was answering while others were answering as well. Somehow Mr. Cowen was channeling my response.

Awwwww.....man. I only had 2 wires left to solder in for my homemade 6080 -> dual 845 adapter. And now you're raining on my parade. Fine. I'll try it in the Darkvoice first.

 

[Paladin79]

Awwwww.....man. I only had 2 wires left to solder in for my homemade 6080 -> dual 845 adapter. And now you're raining on my parade. Fine. I'll try it in the Darkvoice first.

Friends and I are involved in a wager where I have to build a class A speaker amp using some very strange tubes.

https://www.ebay.com/itm/GU-50-OTK-...381724?hash=item3b4c7dc69c:g:FokAAOSwroxfNR8L

Unique tube holders, unique sockets and as far as I know there are no substitutions out there. The amp may be Cowen proof by the time I am done.

 

[Ripper2860]

Riiiiight. As if anything could ever truly be 'Cowen-Proof'.

 

[LoryWiv]

Okay, i am looking a pair of Raytheon vt-231 on ebay and i think i might give those a shot. In the mean time, i m gonna try my svetlanas with my cv-181s and report back. I didnt pay much for the rca 6as7gs, so if i have to replace those, it wont be too bad. I just want something that will make my elise sing in harmony with my VC and Auteur.

Hi @shafat777. I also tried RCA 6AS7G in Elise and found them a bit bloomy (sloppy bass to be blunt). I agree with others it may be best to try different powers before rolling drivers too extensively, and the stock Elise powers are just OK IMO. Best options I've found as powers are GEC 6080 (installed in photo below) aand new production Genalex Gold Lion KT88's run with adapters from @Deyan. With either of those as powers, I've had good results with various drivers including Brimar 6SN7GT and adapter-requiring alternatives. I also used the new production Tung Sol 6SN7GT for quite a while and while it is warm leaning the bass is decently controlled. It is an amazing value and good all arounder, and as a new production tube doesn't require the "hunt" (admittedly that can be part of the fun though). Good luck!

 

[Tom-s]

Unique tube holders, unique sockets and as far as I know there are no substitutions out there. The amp may be Cowen proof by the time I am done.

That's only until someone notes the GU50 is based on a Telefunken LS50 that is close to the family of FL152 -> EL152, EL153 and EL156.
Here's a sample from that family in my collection.

 

[Paladin79]

That's only until someone notes the GU50 is based on a Telefunken LS50 that is close to the family of FL152 -> EL152, EL153 and EL156.
Here's a sample from that family in my collection.

I had heard of them but right now I am limited on what I can use. Down the road I will search for some.

 

[Paladin79]

This tube arrived today, I will have to try various power tubes. Mids and highs are quite good but the jury is out on the bass so far.

 

[Mr Trev]

Philips black glass? Anyone?
https://www.ebay.ca/itm/NOS-Philips...ss-1950s-New-in-Box-1-No-Reserve/274566191298

 

[bcowen]

This tube arrived today, I will have to try various power tubes. Mids and highs are quite good but the jury is out on the bass so far.

Sweet!

I finally got off my butt and wired one of these up today. Melz certainly didn't make it easy. In the Mullard CV3986 I did a while back, there was a distinctive gap between pin 1 and pin 9 for identifying the leads. No such gap in the Melz -- all 8 leads are equidistant around the bottom, and there's no notch, bump, or marking in the glass to identify pin 1 or 8. Fortunately the cathode, grid, and anode leads for each triode are mirror images of each other, so once identifying the heater leads the rest was pretty easy to guess...and I was lucky enough to get it right the first time (at least as indicated by the Hickok). Have it burning in for a bit now, and looking forward to see if it holds a candle to the (much) pricier 1578's and 6N8S's.

 

[bcowen]

Looks rather un-elegant in the Elegant Incubus, but it doesn't sound that way. On first listen it was pretty raw (and fatiguing). After about 4 hours of play, the top end has smoothed out quite nicely and has nice detail without fatigue. Great bass thump, but lacking fullness and bloom in the mids. Enough promise though to keep it going and see what develops after it gets 20-25 hours on it. If it's a typical Russkie that will make a substantial difference.

 

[Mr Trev]

I could make some crass, frat-boy jokes right about now…

 

[bcowen]

I could make some crass, frat-boy jokes right about now…

That's @Ripper2860 's job. Just a public service announcement to preclude development of a frat-boy fight here.