The Stax Thread III

[Sound Eq]

I am not a fan of the Mjolnir amps. They are ok, but overpriced IMO, the case work is poor / basic. The PS in many of his amps is not following KGs design and scaled back. I would look for a nice used KGSShv or KGST. The new Stax T-8000 is bad, very weak sound for the money. The Trilogy H1 is not much better. Maybe approach Headamp for a deal on the BHSE?

Or go planars and use a speaker amp, that is what I have done. SET amp with planars is heavenly.

Back on your topic, the Stax amps have always been the ear link, just not driving the 009 or 007s to their potential IMO.

thanks for the answer what bout using ifi ican pro with ifi iesl, would that be close to KGSShv amp or are we far away with using 007mk2

 

[astrostar59]

Can't offer on that, as never heard the iFi audio amp. But in the recent past amps that try to do both tend not get to a higher level on sound quality. I think you are best deciding if Stats of dynamics are your destination. If stats, go for a dedicated stat amp, but not a Stax amp.

 

[JimL11]

thanks for the answer what bout using ifi ican pro with ifi iesl, would that be close to KGSShv amp or are we far away with using 007mk2

The iESL uses a capacitor bank for the bias supply which is disconnected from the AC during use so therefore noise free. Stax, Sennheiser and Gilmore all use a simple voltage multiplier circuit connected to the AC power supply at all times, which is more than adequate. AFAIK, nobody has ever complained of the bias supply being too noisy, so this seems like a waste of effort. No idea of the sound, but the fact that they wasted money and engineering time on a peripheral support circuit doesn't give me a lot of confidence.

The Trilogy H1 that astrostar59 mentions is another overpriced item. It is a simple 4 tube circuit, similar to the TubeCAD circuit designed in the 1980s and published in 1999, and should retail in the $1000 range - at least, that is the price range Schiit considered for a similar design for a few years ago.

NOTE: comment modified 3/29/19 at ll PM MDT.

 

[bluesaint]

thanks for the answer what bout using ifi ican pro with ifi iesl, would that be close to KGSShv amp or are we far away with using 007mk2

I'll be able to offer that answer in a few weeks when my carbon arrives from Denmark. Right now im listening through full ifi stack.

 

[georgep]

thanks for the answer what bout using ifi ican pro with ifi iesl, would that be close to KGSShv amp or are we far away with using 007mk2

I would go with a dedicated electrostatic amplifier instead of a transformer-based solution.

KGSSHV is a great value - not sure if anyone is building these anymore, so there might only be used option. The KGSSHV Carbon is a much better amp, and there are affordable builders out there, depending on where you are located, or buy used. The Stax amps can be good if you listen at low volume levels, and are better with the 009 rather than the 007.

As a side note. Just noticed that the ifi iesl oddly indicates that it is compatible with the Orpheus system, displays a pair of current Orpheus (HE1) headphones, and yet does not have the appropriate jack and I highly doubt it would even be compatible with the current Orpheus, given its internal circuitry, even with an adapter. So not sure what they are about or who they are trying to market to.

 

[Sound Eq]

ifi states the below when iesl is used with ifi ican pro

"When combined with our Pro iCAN, the drive voltage to electrostatic headphones can be as high as 730V RMS, which is higher (and louder) than any other commercial amplifier out there."

 

[georgep]

The iESL uses an expensive and totally un-necessary battery supply for the bias. Stax, Sennheiser and Gilmore all use a simple voltage multiplier circuit which is more than adequate. No idea of the sound, but the fact that they wasted money and engineering time on a peripheral support circuit doesn't give me a lot of confidence.
... .

Weird, just noticed that the "super special" capacitor they picture is a $0.60 300v cap (even cheaper at volume), yet they describe it as a 1000v cap. Looks like 12 of those bad boys make up the battery.

Edit: double checked the datasheet - 300v AC, and 1000v DC, so that's fair. Edit 2: reading the data sheet further, it indicates if they are run in DC above the rated max VAC, then essentially all bets are off for the stated performance of the cap - why would they spec this part? Why not spend an extra $1 per cap and get properly rated 1000v caps?

 

[JimL11]

hi, I do not know where else to post as it seems I tried in other threads but no answers, so maybe here I will get some answers

does it have to be only the expensive model to feel the difference between stax 007TII and those from Mjolinr audio, to be used with 007 mk2 or 009 s, so what bout those from mjolnir in the price range of 2000-3000 usd range, are those a big upgrade to stax 007tII. And what would such an upgrade provide in terms of sound . To be honest I am not planning to spend 5k or 6K usd on an amp for stax


what bout just using an ifi iesl with my ifi ican pro, would that not be as good as some of the recommended mjolnir amps

currently i have 007 mk2 with 007tii -- using chord hugo 2 as a dac-- i adore the sound

planning to get the new 009s or if the rumours are true a bout a new omega that will come out

also have 407 and 307 which are fine

what other models are worthing adding to the collection besides L700 and L300 LE

Just noticed you said you have a SRM-007 and like the sound. If that is the case, another option would be to modify the SRM-007 by substituting constant current loads for the plate resistors. This would be less than $100 in parts, and would more than double the effective power of your amp. It is a relatively simple mod, and would bring the circuit close to a KGST although without its regulated power supply. Here is a photo of a 007 that spritzer modified (he also changed the tubes to 6S4A in place of the 6CG7s but you get the idea). Even if you had someone do it for you it would still be much less expensive than the iESL.

 

[JimL11]

Weird, just noticed that the "super special" capacitor they picture is a $0.60 300v cap (even cheaper at volume), yet they describe it as a 1000v cap. Looks like 12 of those bad boys make up the battery.

Edit: double checked the datasheet - 300v AC, and 1000v DC, so that's fair. Edit 2: reading the data sheet further, it indicates if they are run in DC above the rated max VAC, then essentially all bets are off for the stated performance of the cap - why would they spec this part? Why not spend an extra $1 per cap and get properly rated 1000v caps?

DOH! You are correct, it isn't actually a battery at all, just 12 capacitors adding up to approx 0.26 uf. OK, so it isn't that expensive, mea culpa. I withdraw my previous criticism. The Stax and KG circuits use 0.1 uf cap as the final one in the chain, so not a lot of difference there. Apparently they do have a circuit to disconnect the charger from AC power, unlike everybody else but doubt that makes any significant difference. Previous comment above modified.

 

[Zhanming057]

I am not a fan of the Mjolnir amps. They are ok, but overpriced IMO, the case work is poor / basic. The PS in many of his amps is not following KGs design and scaled back. I would look for a nice used KGSShv or KGST. The new Stax T-8000 is bad, very weak sound for the money. The Trilogy H1 is not much better. Maybe approach Headamp for a deal on the BHSE?

Or go planars and use a speaker amp, that is what I have done. SET amp with planars is heavenly.

Back on your topic, the Stax amps have always been the ear link, just not driving the 009 or 007s to their potential IMO.

Mjolnir goes on record about using better components than Headamp - but that's neither here nor there. I agree on the casework, and for $4,000 there's no reason that he should be using $50 housing's. Getting proper finish work would go a long way toward making his amp look nicer.

I found the T8000 okay with the 009 - it's not so much "weak" as deliberately going for a softer and gentler signature. I'd still take the BHSE and the Mjolnir Carbon over the T8000 though.

 

[georgep]

ifi states the below when iesl is used with ifi ican pro

"When combined with our Pro iCAN, the drive voltage to electrostatic headphones can be as high as 730V RMS, which is higher (and louder) than any other commercial amplifier out there."

That is because the iesl is not an amplifier. I suspect the WOO and Stax boxes would be similar depending upon what amplifier is connected to them.

 

[-HaVoC-Tzu-]

Spent 1 hour switching DACs and testing. Between X1S vs WA7 vs HDV 820 vs Chord Hugo 2. Very clear difference.
ADSR, and sound stage change (might be an effect of better ADSR) and just more detail in the Chord Hugo 2.

 

[Melody Spalti]

Is it time for someone to post photographs of the D10? It should be manageable and fairly straightforward.. to have done one evening.

Sunday nights work nicely : )

PerhapsPerhaps U though, but
Did they gimp it in some small way? And resistor load or transistor (current source?) load yet to be found outside, -- that is only in the 727? Can the D10 amplifier be slightly modified or improved in some way?
Pics per pm or listing here or in the 002/003 thread for continuity and stability-archival retrieval purposes may be in order.

At $760 or 795 after discount from retailer it is a lot of money and I know I would love a picture of how jammed up it is inside, potentially minute and better circuit details.
Especially for those of us learning about electrostatic.

 

[kevin gilmore]

if you ask the right person, pictures are available. (not me)
The thing is stuffed on the insides.
The main devices are apex pa443 opamps running on a total power supply voltage of +/-175v
You can't increase the voltage which means the voltage swings limit the maximum volume.

No modifications of any kind seem possible.

 

[chimney189]

Would anyone have any recommendations for an amplifier for the JADE II electrostatic headphone?
I'm looking for $1,000 or under if possible, as the amplifier that it comes with doesn't seem too great.