[warrenpchi]

Two days next year?

  Two days sounds like a interesting idea. I think Can-Jam and T.H.E Show are like 3 days... More equipment to cover and perhaps in not such a hurry.

 
 
Yeah, definitely.  We're already at the point where most events would have crossed over into a multi-day format, so I think it being AT LEAST two days is now a necessity.

 

[Jon L]

 
 
The final question is why build such an amp at all? There are plenty of excellent, professionally designed DIY electrostatic amp projects available. None of them involve DHT's however. I've been an SET/DHT fan for years. I've always wondered what a top-tier Stax headphone would sound like with a full scale DHT amp. It's been a long haul, but I'm pleased with the results and intend to make this amp my "daily driver" (at least until the next project).
 

 
So sad I didn't get to the meet to hear this amp.
Hope people realize how ridiculous it is for this DHT electrostat amp to even exist !

 

[bozebuttons]

   
Hey dude, there are like six women in all of Head-Fi.  One was in Texas at the time of the meet.  Another didn't show up.  And four women were at our meet.  I'm pretty proud of that. 

  Now if only I could get Grado to come to one of our meets (because they NEVER EVER go to meets), then my meet organizer bucket list will be complete.

Great job to the organizers.
 
 
Just a little tidbit about Grado never going to meets,the first 4 NY regional meets in 2002-2004 where held at Grado Labs,John also came to the the first national meet in Queens
with the prototype GS1000s.
 Now to get back on track with the meet impressions,Post them if you have some for those of us who weren't able to attend.

 

[warrenpchi]

  Just a little tidbit about Grado never going to meets,the first 4 NY regional meets in 2002-2004 where held at Grado Labs,John also came to the the first national meet in Queens
with the prototype GS1000s.

 
Yeah but you NY guys are on a whole other level, so you don't count. 

 

 

[bozebuttons]

   
Yeah but you NY guys are on a whole other level, so you don't count. 

 

We set the trend but you guys picked up the ball & ran with it

 

[audiofrk]

Huge thanks to Ethan and Warren for running a very well organized, well attended, and hugely fun meet. Absolutely killer raffle! Lots of new faces and the largest assembly of headphone related vendors I've ever seen. With the near extinction of "brick and mortar" audio stores, meets like this are about the only way one can audition a large variety of gear, establish personal preferences, and began to assemble a personally tailored audio system.

I enjoy the gear, but after nearly a dozen meets my primary focus is on the people. I always get a recharge from familiar faces and never fail to make a new friend or two.

I appreciate the comments about my DIY 845 electrostatic amp.I have a tradition of bringing a new amp to each meet. Often these amps are less than a week old when they're shown. Some are hits and some are misses, but all criticisms and comments are welcome.

Despite the layout sheets, I think a fair number of people were unaware of the personal rigs around the corner from the main commercial rooms. Perhaps a few signs would be helpful next time around.

For you people that never got down our way, you missed quite a bit. In the Warner Center room we had a vinyl rig with a vintage Sherwood receiver. This is a great, but inexpensive way to drive an HE-6. We also had a Bottlehead kit amp with an HD-600. Bottlehead kits are not only one of the best ways to drive HD-600/650's, but they are perhaps the best entry point into tube DIY there is. We also had a very nice pair of solid-state kit amps that drove the LCD-2 with ease.

Across the hall from us were the original and best of the HD-800 modders with their latest improvements. Also in the room was one of the most advanced computer based audio systems I've ever seen. To top it off, there was Head Amp/ SR-009 Stax system who's owner builds his own electrostatic headphones. Last but not least, the two rooms probably contained a century or more of audiophile experience. We like to share. So come on down next time!

Thanks again Ethan and Warren. You guys are great!

 
 
ummmmmm am I the only head-fier that read this and though "MINI MEEEEETTTTT!!!!!!! I'LL PAY A $15 ENTRANCE FEE JUST TO LISTEN TO THESE SET UPS AND TALK TO THEIR OWNERS!!"

 

[Sko0byDoo]

 
 
I've received a couple of pm's asking about the design and construction of my electrostatic amp, so here's a brief description.
 
First and most important thing to note is that there are considerable electrical safety issues involved in the design, construction, and operation of an amp like this.  Many people consider consider amps like this inherently dangerous and unsuited for home use. The raw HV is 850VDC. Unless you have considerable experience working at these voltage levels, you should not attempt this or any similar construction project. Your first mistake could well be your last.
 
Cost is another consideration. Most of the parts were recycled from previous projects. Some are custom built. If I'd had to buy everything new, component costs would have run close to $3k. Building tube amps is my hobby, I don't keep track of the time I put into my projects, but I'm guessing there's a couple of hundred hours here. Bottom line is that you do a project like this because you enjoy the process. It certainly doesn't save money even compared to the most expensive commercial amps.
 
Now that the disclaimers are finished, on with the description. Basically this is a very traditional, very simple, three stage , single-ended, directly-heated triode transformer-coupled tube amp. The major difference between this amp and a speaker amp is the output transformer, which is a custom wound Electra-Print unit designed to drive high impedance electrostatic headphones  rather than low impedance speakers.
 
The first stage is a CCS loaded type 76 triode, which is an early predecessor to the 6SN7. The CCS is an IXYS10M90 solid-state current regulator. Pete Millett is the source of this idea. The 76 is cathode biased using a pair of green LED's. Output of the 76 is directly coupled to the second stage, which is a triode-connected 6V6, a small power tube.
 
The second stage 6V6 is loaded and connected to the third stage 845 via a 1:1 7k interstage transformer. Bias on the 6V6 comes from the direct connection on the plate of the 76 to the grid of the 6V6.
 
The output stage  is a directly-heated 845, which in my opinion is perhaps the finest audio output tube ever made. Unfortunately I'll never be able to afford an original pair, but the Chinese reissues have been improving over the years, and some of them have gotten quite good. One reason I built this amp was to try out some of the modern 845's, particularly the metal plate versions. The 845's plates are run at 60mA/700V, while well below their dissipation levels, is still a very linear operation point. Bias is "fixed" -100V, supplied via the secondary of the interstage transformer. Overall gain of the amp is a little over 600. Voltage swing is about 600Vrms. I have no ideal what the distortion measurements might be, but I assume they would be in line with other amps of this type.
 
Another reason I built this amp was that I wanted to try a fully regulated power supply for the 845's. This is something that is rarely seen in large SET amps. The power supply ( chassis on the left in my photo) starts off as a simple soliid-state rectified CLC type. Only thing unusual here is that I used motor-run oil capacitors in the filter. The raw DC (about 850V) is fed into a tube regulator, The regulator is pretty standard with the exception of the large 13E1 pass tubes. These tubes are one of the few types that was specifically designed for high voltage/high current pass duty. Output of the regulator is 700V, which provides the B+  of the 845's and the input supply to the second 13E1 based regulator. The second regulator provides about 400V to the first and second stages of the amp.
 
The final question is why build such an amp at all? There are plenty of excellent, professionally designed DIY electrostatic amp projects available. None of them involve DHT's however. I've been an SET/DHT fan for years. I've always wondered what a top-tier Stax headphone would sound like with a full scale DHT amp. It's been a long haul, but I'm pleased with the results and intend to make this amp my "daily driver" (at least until the next project).
 
Thanks for the interest!

 
Very cool, Frank!  Thanks for the details.  I missed out on the meet and to listen to your amp.  Your works look awesome as always.

 

[ccash]

Does anyone know the name of the software that a lot of the vendors were using to piggyback iTunes on? I can't remember the name for the life of me, and I'm not too up on the high-end options for playback from a computer.

I remember the Mr. speakers table was using it, if anyone recalls.

Thanks!

 

[ohhgourami]

Amarra?

 

[Sorrodje]

 
 

 
 
I read carefully your post but missed that there's a lot of Metrum Dacs on this pics. It that Yours FrankCooter ?

 

[dsound]

Does anyone know the name of the software that a lot of the vendors were using to piggyback iTunes on? I can't remember the name for the life of me, and I'm not too up on the high-end options for playback from a computer.

I remember the Mr. speakers table was using it, if anyone recalls.

Thanks!

I believe it was Pure Music

 

[ccash]

  Amarra?

That's it. Thanks!
 
Thanks dsound too.

 

[moedawg140]

  Amarra?

 
Yeah, I knew it started with an "A".  I was thinking...Aurora?  Then I looked for it, and in iTunes they showed a player that did not look like the Amarra player.  With that said, I wonder if the vendors/exhibitors used the Amarra Hifi, 3.0 or Symphony 3.0 With iRC version(s) and/or which one they used the most... 

 

[Greed]

Audirvana is the program that has iTunes integration. 

 

[bpeng]

Terrific meet and much thanks to the organizers!
 
I think my small amp (The Bravissimo) was skipped over by many people as it was not what people expected from high-end, but any reports by those who DID hear it are welcome. I know Gilley87 and GoldenSHK have already remarked on it.
 
Mike