New RSA amp...

[Elephas]

A-10 vs. Woo electrostat amp vs. BHSE for HE90

Which of the three amps would you choose to drive the HE90?

I assume that the BHSE would be a better choice for the Stax O2Mk1 or O2Mk2. But the choice doesn't seem as clear for the HE90.

People at the recent Detroit mini-meet have posted about the HE90+A-10 combo as well as other gear. Jude says the HE90+A-10 is probably the best headphone system he's ever heard. Link

Given that the HE90 is the priority, might the A-10 be a better match than the BHSE? Or the new Woo electrostatic amp?

[Dusty Chalk]

You're trolling, right? Most of us haven't heard most of those amps.

[Duggeh]

When chosing between the BHSE, A10 and WooES for the HE90, one should pick the Aristaeus.

[Asr]

Shouldn't the question be between the Aristaeus, WES, and A-10? Now if you sent your Aristaeus to CanJam '09, trusted people could find out for you, because as it is, no one will be able to offer any opinions until at least CanJam '09.

^ what Duggeh said. Keep the Aristaeus, I say!

[spritzer]

We can just write the A-10 off right away as SRPP circuits simply aren't suitable for driving electrostatics properly, even if people with zero experience claim they can. We all know what effect the HE90 has on people that have no experience with 'stats and the He90 is also one of the easiest headphones to drive.

I've always preferred the HE90 with AC coupled amps or some that aren't as brutally revealing as the BH. With that in mind then I'd stick with the Aristaeus or try out the Woo. You could even ask Justin to build you a bling Aristaeus with some Mundorf caps.

[Elephas]

You're trolling, right? Most of us haven't heard most of those amps.

I realize very few have heard these amps and probably no one has heard even two.

I was just reading about the A-10 and for some reason heard "voices" and felt some "urges."

Now if you sent your Aristaeus to CanJam '09

A hint?

Someone in Florida has an Aristaeus, I believe. So plenty of people have heard the HE90+Aristaeus. Maybe some of them will post impressions from CanJam.

I can't wait for CanJam!

[cclragnarok]

I thought only eartwitter bought a Coriolan?

Lobstersauce apparently bought one too:

AudiogoN ForSale: Rudistor Coriolan 2 electrostatic stax

[spritzer]

That is Kim's (peeradonn) amp unless somebody else bought all those heat resistant tube dampers. That means there are 2 amps out there and there are probably some other poor souls that were fooled by the grainy pics and stupid Latin inscriptions.

[Icarium]

Haha I like how it has that stupid latin quote on it like his RP010B

[Icarium]

I realize very few have heard these amps and probably no one has heard even two.

I was just reading about the A-10 and for some reason heard "voices" and felt some "urges."

A hint?

Someone in Florida has an Aristaeus, I believe. So plenty of people have heard the HE90+Aristaeus. Maybe some of them will post impressions from CanJam.

I can't wait for CanJam!

Oh what? You are coming out?

[Elephas]

No, I didn't mean I'm going to attend. I'll just read about everyone having fun and be envious.

Only ten A-10 units available at the introductory price and apparently only six of those left!

[spritzer]

I feel very sorry for those four unfortunate souls.

[GPH]

I feel very sorry for those four unfortunate souls.

Spritzer, pardon my ignorance, but what makes you think Ray's amp will suck so much? There are no published internal shots as far as I know and you sure as hell weren't at any of the meets where the A-10 was present. It seems a little bit presumptuous to be as critical as you are.

[spritzer]

I've got to keep this short but in essence the SRPP design and tubes used are both utter fail. The tubes will either be run far out of spec (so they won't last long) or this amp has the lowest output power of any amp, bar the SRM-212 (and it's variations) and the portable Stax amp. Now he could use output transformers but the SRPP circuit still will not like the reactive and capacitive load present. Now take price into account and that you can get the new Woo amp plus a SR-007Mk2 for the same price as the A-10 and the Woo uses the same or even better parts.

[GPH]

I've got to keep this short but in essence the SRPP design and tubes used are both utter fail. The tubes will either be run far out of spec (so they won't last long) or this amp has the lowest output power of any amp, bar the SRM-212 (and it's variations) and the portable Stax amp. Now he could use output transformers but the SRPP circuit still will not like the reactive and capacitive load present. Now take price into account and that you can get the new Woo amp plus a SR-007Mk2 for the same price as the A-10 and the Woo uses the same or even better parts.

So what you're saying basically is, even with best intentions, one could not design a good amp for electrostatic headphones using a SRPP design?

[manaox2]

So what you're saying basically is, even with best intentions, one could not design a good amp for electrostatic headphones using a SRPP design?

And these tubes. Don't forget the tubes.

[spritzer]

So what you're saying basically is, even with best intentions, one could not design a good amp for electrostatic headphones using a SRPP design?

Yup...

And these tubes. Don't forget the tubes.

...and yup. Justin posted a link to a TubeCad article that tackles this very issue. There are ways to minimize the effects on the circuit but the "fixes" are way beyond anything we've seen Ray do before and it would be far better to just use some other circuits. There isn't exactly a shortage of circuits to steal...

[kevin gilmore]

Ray may actually not know what the design is, as he had his engineer that also

does all his circuit board layouts do the thing. So it could be srpp, or it could be

constant current, both of which are otherwise identical except the output is

taken from either the cathode of the top tube (srpp) or the plate of the bottom tube

(ccs). Tests i did last weekend showed that 5687's start to arc and do all sorts

of nasty things over 425 volts plate voltage. So the power available from this

amplifer could be anywhere from a little bit low (425) or a lot low (300)

Transformers would definitely help some as the output impedance of the srpp would

see roughly a constant load impedance.

In any case for an amplifier priced like the A10, there should be bigger output

tubes that can handle at least 800 volts.

Then again -=germainia=- really likes ray's hr2. So what the hell do i know

[manaox2]

Then again -=germainia=- really likes ray's hr2. So what the hell do i know

Shes also getting thwacked with a by Jude in the Detroit mini-meet impressions thread on HF.

[luvdunhill]

Tests i did last weekend showed that 5687's start to arc and do all sorts of nasty things over 425 volts plate voltage

please repeat for the 6S4A

[manaox2]

please repeat for the 6S4A

Don't do it! Do it!

[Dusty Chalk]

Team Arcy Sparky wants you to post pics if you do. Yes, even your trademark huge-ass pics.

[luvdunhill]

Team Arcy Sparky wants you to post pics if you do. Yes, even your trademark huge-ass pics.

shit, I didn't even think about pics... definitely, dew eet!

[nikongod]

shit, I didn't even think about pics... definitely, dew eet!

video>photos

[kevin gilmore]

Bad day today. Saw a 14.4kv 1000amp commonwealth edison line short against another

of same and blow a hole in the road about 20 feet wide. Sure wish i had my video

camera for that. Whole building lost power for 55 minutes.

As for 6s4's you can push them to about 750 volts. They are rated at either 500 or

550 volts depending on which data sheet you read.2000 volts peak, but that really

does not count for class A. 5687's are rated at 300 volts.

The 6s4's are single triodes with a 200 volt heater to cathode. So they are a whole

bunch easier for many designs.