eXStata DIY Electrostatic Amp for Intermediate DIYers
Dec 18, 2009 at 5:07 PM Post #1,666 of 2,970
Dec 18, 2009 at 7:05 PM Post #1,668 of 2,970
Quote:

Originally Posted by BoilermakerFan /img/forum/go_quote.gif
Looking at the Hybrid boards and the heater wiring, is there any reason why I couldn't wire the 4 heaters in series to run them at 12.6Vdc?

I have dual 6.3V secondaries of my power transformer and nice little regulated DC PSU board.



You should not do this because of the built-in heater biasing circuit.
 
Dec 18, 2009 at 7:27 PM Post #1,669 of 2,970
Quote:

Originally Posted by runeight /img/forum/go_quote.gif
You should not do this because of the built-in heater biasing circuit.



Thanks Alex. I'll just keep it 6.3Vac...
 
Dec 18, 2009 at 7:59 PM Post #1,670 of 2,970
Quote:

Originally Posted by luvdunhill /img/forum/go_quote.gif
Hey Al, how do the new amps with HE-60 compare to Alex's old ES-1/SR-Ω combo?


Boy, you'd trust my memory? And, I am sure this is a set-up, but, I'll bite. :wink:

Actually, I never heard that combo, for two reasons - a) Alex would not (and reasonably so) bring the Omega to a meet, and b) he sold them (in 1q2007 iirc) before I got a chance to hear them at his house, oh, and before the amp developed Singlepower-itis.

I was VERY familiar with that particular amp, as Rob let me listen to it on several occasions, at meets and his house, both with his OII, and with my he-60. The amp also had a very pricey set of Telefunken driver tubes, which was, as one would imagine, superb - and, all told that amp cost about $4500.

Caveat: IMHO!!!!

So, to hold anything ceteris paribus (from my fading memory, with declining capacity, and creeping tinnitis) it would be fairer for me to eval against the BH or even your KGSS. It compares favorably with those amps (my source, and the he-60), but no specific areas better or worse except IIRC the bass on eXStata is better than either KG design (of the builds I've heard, my tubes, my source, my music selection, my areas of interest, etc), and, from what i can tell, no weaker in any area.

I know this differs from your experience with the OII and the SS proto version, but we do need a LOT more A/B, with better overall critical listening conditions.

Now, IFF Vulcan will power up, and actually run (given it's 3x places I could have screwed up, not to mention just it's wiring scheme), then I can make a truer comparison side by side, and maybe BH will benefit from angelic intervention (found a shipping box!!!), and that will be available by the January Dallas meet IFF the tranny isn't burned (the SumR unit spec'd for Vulcan can be used in BH worst case).

BUT, I have not heard my latest version (JUST got back from picking up the LED resistors at Tanners, and should have all that sorted by early evening), so I will be really vocal about comparisons, with a complete SWOT analysis as soon as I think it is burned in - hopefully by Monday. I could not do that with the proto, and my reservations there led directly to the ccs in this version - all so I can listen to 'Tool' with impunity, or, extreme prejudice.

Now, I REALLY cannot wait to have the take-it-to-the-mat discussions regarding flavor of 6s4a (hey, at least we are only arguing about ONE tube), whether Tung-Sol or Amperex or some odd matched getter/flashing version is best, not to mention what happens with cryo...

So, in summary, no opinion - iirc, Alex raved about he-60 with BH, then liked the ES-1/SR-Ω combo better, albeit after paying about $8.5k for the amp and phones, and had a second pair of SR-Ω at $4kish, so he was rather heavily invested. Not that the $ expenditure EVER influences our opinions about how something sounds...
 
Dec 18, 2009 at 8:06 PM Post #1,671 of 2,970
Quote:

Originally Posted by pabbi1 /img/forum/go_quote.gif
So, in summary, no opinion


heh, not a setup at all. Just never thought to ask about it
smily_headphones1.gif
 
Dec 18, 2009 at 11:52 PM Post #1,672 of 2,970
Good idea though - getting Alex's opinion on eXStata - and something for us to accomplish at the Dallas meet as I understand there will now be a BHSE in attendance as well.

OK, off to some errands, then hopefully get this party started... again.
 
Dec 19, 2009 at 4:02 AM Post #1,674 of 2,970
No, Alex @ apuresound. Now, had it been you, we' might have _started_ at the 1400Vpp spec...
tongue_smile.gif
 
Dec 19, 2009 at 4:07 AM Post #1,675 of 2,970
Quote:

Originally Posted by pabbi1 /img/forum/go_quote.gif
No, Alex @ apuresound. Now, had it been you, we' might have _started_ at the 1400Vpp spec...
tongue_smile.gif



Ask him why he's not making cables for the ESP/950s anymore, you know, if you can casually work it into the conversation. Something subtle like, "Hey Alex, why aren't you making cables for the 950s anymore? Now that DIY'ers are saving so much money with the eXStata, they have money for a great cable to really make the 950s sing..."

Thanks Al.

beerchug.gif
 
Dec 19, 2009 at 5:06 AM Post #1,676 of 2,970
OK, everything is dialed in, but my rails are at 311/312. About 15 minutes plus at this point.

With the resistor load, T1/T3 to ground was 330. rails 305v (T1/2 and T3/4 were right at spec).

Just for reference, I used 100k 3w for r23/r24, and the led is plenty bright to indicate power. The 68k left a nasty scorch on the board, but no pad nor trace damage - again with my line voltage, 269jx, etc.

I'll mention that to Alex, but he's offline atm (I have him on IM) - I'd be real surprised if it is anything more than lack of good flat cable, but I need to know for my brother anyway.

Oh, and another motivation shot - eXStata #4 lives.

xstat.jpg
 
Dec 19, 2009 at 6:44 AM Post #1,677 of 2,970
Quote:

Originally Posted by Hopstretch /img/forum/go_quote.gif
I think we can make that happen.
smile.gif



I think we should just make it a straight up Massachusetts-area meet if you're down. Haven't had one in a while.
 
Dec 19, 2009 at 1:49 PM Post #1,678 of 2,970
Quote:

Originally Posted by pabbi1 /img/forum/go_quote.gif
OK, everything is dialed in, but my rails are at 311/312. About 15 minutes plus at this point.

With the resistor load, T1/T3 to ground was 330. rails 305v (T1/2 and T3/4 were right at spec).

Just for reference, I used 100k 3w for r23/r24, and the led is plenty bright to indicate power. The 68k left a nasty scorch on the board, but no pad nor trace damage - again with my line voltage, 269jx, etc.

I'll mention that to Alex, but he's offline atm (I have him on IM) - I'd be real surprised if it is anything more than lack of good flat cable, but I need to know for my brother anyway.

Oh, and another motivation shot - eXStata #4 lives.



Thanks Al. The story I heard was concern about voiding the warranty, which it doesn't since Koss has a No Questions Asked LTW policy. I'd just have to take the cable off before shipping them in... I haven't talked to or asked Alex directly, but since you know him, it was easier that way.
 
Dec 19, 2009 at 5:37 PM Post #1,679 of 2,970
Listening with the electrets (SR-40), and will allow a few hours burn in with them (well, or as long as I can stand it before plugging in the he-60). Wired my pot diametrically opposite of the attenuation curve (yes, Marc, as you knew I would), but will sort that out later on today, even if it "works" now.

But, she is up and running, making even the most humble stats sound good. Who said electrets don't have any bass or soundstage? Looks like my 'spare' Hybrid will be finding a new home.

Oh, and for you guys sitting on the sidelines _hoping_ Runeight does another board run, you might want to start an interest check thread to start collecting names, and versions desired (SS or Hybrid), as it will take some serious love (quite appallingly missing so far) to convince him this effort is worth continuing.

So many toys, and it isn't even Christmas yet. Thanks Santa Alex!
 
Dec 19, 2009 at 5:46 PM Post #1,680 of 2,970
Quote:

Originally Posted by pabbi1 /img/forum/go_quote.gif
Listening with the electrets (SR-40), and will allow a few hours burn in with them (well, or as long as I can stand it before plugging in the he-60). Wired my pot diametrically opposite of the attenuation curve (yes, Marc, as you knew I would), but will sort that out later on today, even if it "works" now.

But, she is up and running, making even the most humble stats sound good. Who said electrets don't have any bass or soundstage? Looks like my 'spare' Hybrid will be finding a new home.

Oh, and for you guys sitting on the sidelines _hoping_ Runeight does another board run, you might want to start an interest check thread to start collecting names, and versions desired (SS or Hybrid), as it will take some serious love (quite appallingly missing so far) to convince him this effort is worth continuing.

So many toys, and it isn't even Christmas yet. Thanks Santa Alex!



Did you wire your POT as a shunt? If so, what R did you use on the inputs?

Actually, I'll take that back but leave it standing, you didn't wire THAT pot as a shunt, did you?
 

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