Electrostatic headphones - dedicated amplifier vs. transformer

[stroshek]

Hello,

this is my first post here.

I was wondering if anyone could shed some light on the differences between using dedicated voltage amplifier and step up transformer with speaker amplifier to drive electrostatic headphones.

I've tried electrostatic headphones recently and I am thinking about getting a pair. I could build an energizer around two Lundahl LL1630-PPs and I was looking for any info on pros and cons of such solution.

Cheers.

 

[egellings]

The leakage inductance of a step-up transformer can interact with the capacitance inherent in electrostats to produce a sizzly, rising high end of the frequency spectrum. That would be absent with a high voltage amplifier directly powering the earcups. If the ear speaker and a transformer are designed to work together to eliminate that problem, then the combination could work well.

 

[stroshek]

The leakage inductance of a step-up transformer can interact with the capacitance inherent in electrostats to produce a sizzly, rising high end of the frequency spectrum. That would be absent with a high voltage amplifier directly powering the earcups. If the ear speaker and a transformer are designed to work together to eliminate that problem, then the combination could work well.

Thanks! Would you be so kind and recommend any source material for further reading?

 

[egellings]

I can't think of any titles, but you could look at undergraduate textbooks on general electrical principles. I'm not aware of any technical articles on HF peaking specifically in electrostatic speakers.

 

[okok]

there's no stax user here let alone diy this transfomer, no one cares about transfomer amps like 30 yrs?

 

[RayDunzl]

there's no stax user here

None?

Search results for query: stax

www.audiosciencereview.com

 

[egellings]

I had Stax electrostatic headphones years ago, and they came with a direct drive high voltage solid state amplifier that needed no step-up transformer.

 

[Laughing Heart]

Alternatives to STAX amplifiers are limited or crazy expensive,
I'm very happy with a once reasonably priced but old STAX SRD-7 Mk2 transformer box, it's driven by a Crown Studio Reference II power amp, for my SR-L700's which isn't a very expensive setup, especially when compared to similar priced planar or dynamic headphones.

To me this setup is very musical, with a beautiful natural tone to vocals and instruments, great clarity, resolution and spacial imaging, it has an almost speaker like quality,

(my daughter who's completing her masters in film score composition, and definitely not into gear, is always composing or mixing using Logic Pro X, HD650's, Beyer T5p's &/or monitors, I asked her to give my L700's a try, after I set them up, first thing she asked was "are the speakers still on" now she always asks for the L700's)

For me it was better than the top Stax amps, with way more headroom, they can play loud enough to give permanent tinitus, I don't hear any distortion, even at very loud levels, maybe just a compression of dynamics and if I'm not careful I could easily fry the SRD or L700's.
But I've no idea how accurate the setup measures.

I would be happy with a modern Estat Transformer box that is well designed, i.e. a modern take on the SRD-7 Mk2, one that measures accurately.

Spritzer / Moljnor audio builds SRD transformer boxes, using the transformers out of old Stax SRD's, and occasionally Lundahl Transformers, but both are expensive when compared to the original STAX SRD pro units which pop up on Yahoo Japan occasionally for about $350 usd give or take 50.

My 30kg Crown is too big and inconvenient for desktop use,
I'm planning to eventually buy the SABAJ A30a amplifier because of it's unique digital feedback design and I would expect it to not be affected too much by load or impedance / fequency variables caused by the SRD-7 Mk2 and L700 combination.

The final sound quality is very much dependant on the quality of amplifier used to drive the Transformer adapter.

To my ears a well designed Transformer adapter matched with a great amplifier is very cost effective and better than STAX amp offerings.

Hope this helps.