I'm interested in building the Stax Transformer project here: the STAX Transformer as it seems relatively easy to build but I've searched everywhere I can think of but can't find any reviews on this beast.

Has anyone built this project or know of any reviews detailing performance, SQ etc?

Tim

I'm interested in building the Stax Transformer project here: the STAX Transformer as it seems relatively easy to build but I've searched everywhere I can think of but can't find any reviews on this beast.

Has anyone built this project or know of any reviews detailing performance, SQ etc?

Tim

Tim:

Which Stax amps / Earspeakers have you heard?

Well errr......none!

I've only recently become interested in ESL headphones and I intend to audition the Stax 3050A system next week on the way out to a trip to Japan which will hopefully give me an idea on what all the fuss is about .

I'm hoping to check out some used gear over there - hopefully some SR-Lambda's and maybe the SRM-1/MK-2 or the SRD-7MkII if I can find any. They seem a popular beginners choice after reading the phenomenal Stax thread here.

I enjoy DIY and, with one eye on the future I was looking at the Stax Transformer design as maybe a significant upgrade over the SRM-1/MK-2 or the SRD-7MkII mentioned above, hence my interest in the design.

If you are able to demo the Stax line in Japan, I would try and hear the vintage offerings or the SR-007.

The SR-Lambda is a very good headphone, and a great intro to electrostats.

This is really interesting. How much is it going to cost?

This is really interesting. How much is it going to cost?

The price will probably vary wildly based on how much your distributor charges for the Lundahl transformers.

It isn't cheap that's for sure but one can use a simpler bias supply and skip one Lundahl unit there. I would also consider Sowter transformers which are designed for ESL duty but they aren't cheap either. If you are only going to use Lambdas and not one of the Omega or Sigma range then a standard SRD-7 will be more then enough and you can always modify it with better wiring directly to the windings.

How much is the SRD-7? I might be able to get one.

A normal bias SRD-7 can be had for less then 100$ but the SRD-7 Pro and Mk2 units fetch closer to 300$.

So as a compromise, seeing as I already have a SRD-7MkII, would it be easy enough to just change transformers or would other circuits need modding too? If it's as simple as plugging in bigger tranfo's I might have a go, price permitting.

There is an overload protection on the PCB for the transformers (but it should be bypassed anyway for better SQ) but other then that the transformers are on their own. Fitting larger units in the SRD-7 box isn't likely to work out so the best way would be to build a new bias supply and go from there. It's easy to build point to point but there is always the option that somebody draws up a PCB...

I doubt that he meant to fit them in the original box

I are whittlin' foo

Yes, trannies and guts in a bigger biscuit tin so it all fits. If all it takes is a bigger pair to make the SRDs better then which ones to use?

I doubt that he meant to fit them in the original box

One never knows with Gary...

I are whittlin' foo

Yes, trannies and guts in a bigger biscuit tin so it all fits. If all it takes is a bigger pair to make the SRDs better then which ones to use?

That's the rub. There are plenty of 1:25 candidates out there such as push-pull output transformers wired up backwards and even power trafos but none have been tested as of yet. You could go with something very nice such as Sowter or Plitron which are designed for ESL duty but the price...

I are whittlin' foo

Yes, trannies and guts in a bigger biscuit tin so it all fits. If all it takes is a bigger pair to make the SRDs better then which ones to use?

Whittle a wooden dalek and use it for the transformer chasis

whittle a wooden dalek and boil it, smash it, stick it in a stew!