spritzer

Happy birthday Doug!!

The ESP7 is just a ESP6 with all the electronics moved to a box outside the headphones. The ESP9 was an updated design with a much more complicated energizer that even featured some EQ. I've owned them both (all of the Koss phones actually) and they aren't something I would use regularly. In fact I have a set of ESP9's that I can let you have if you are willing to pick up the shipping. There is some hum in AC bias mode but dead quiet in SB bias mode. Just PM me if you want them...

This is very true and I've received a number of Stax items from Japan which should have ended on the scrap heap rather then Yahoo. Some I've managed to bring back up to spec but it wasn't easy. One SRD-7 I got was so rusty that most of the paint fell off it when I took it out of the box. KK is a great fan of electrostatics and some of his reviews were on the old Simply Stax site. I remember the 4070 and SR-? reviews were there but the Stereophile review is much better. I do concur with his findings though as the older energizers are much better then the new ones.

You need a deputy service and have to pay them a fee as well. There are plenty to choose from so Google is you friend.

http://page6.auctions.yahoo.co.jp/jp/auction/f64514987 http://page17.auctions.yahoo.co.jp/jp/auction/v47307021 http://page.auctions.yahoo.co.jp/jp/auction/103973692 http://page10.auctions.yahoo.co.jp/jp/auction/m51629263 The ones that go even lower are badly marked, in the wrong category and/or not on Yahoo!JP

I of course meant used since the SR-007 isn't avaialble any more unless some dealer has a few in stock. Even one of our own got one for about 1k$... Some go higher then 100kYen bu that's what you would expect of auctions. It's still nice to see the Japanese market is still sane as the SR-? still hasn't sold for 300kYen.

They can be had for as little as 800$ in Japan if you are lucky. The normal price over there is about 1000$ What I don't get is why the hell did he change the coating so something so conductive. It even sounds like he used pure carbon and that is simply idiotic as it absorbs moisture from the air and becomes even more conductive. The goal is to hold a charge or you will just end up with something like the old Koss designs.

All you need is a steady hand and some common sense.

Hehe that is a good one. It isn't really that cold up here and -15

Recabling is dead easy as the connectors are at the bottom of the cup and with Stax it's the center wire to the bias, the one with the marking goes to the stator closest to the ear and the third wire goes to the back stator. Broken line is right and solid is left. Easy as making a cake (which is very easy... ) but it's more trouble to squeeze the Wide PC-OCC cable in there then the SR-303 cable.

Just remember to always cover the drivers with cardboard or something solid when soldering near ESP drivers as a stray drop of flux can destroy them.

It seems to have mostly died down now which is great. A FOTM train headed by those individuals can only end badly as they don't have a clue what is going in the drivers. I also question he wisdom of guy making the phones for the sudden change to a new coating material in the middle of production. From the description it sounds a lot like very clean carbon which is stupid to use with the range of todays options.

Frozen north FTW!!!!

I'm posting more detailed schematics of the SRA-12S after a request:

It's about 95% rock/metal for me and I love the SR-007 but it's the amp that makes or breaks them along with proper fit. Since the current draw is highest at the lowest bass and highest treble in ES drivers this is no surprise. Stax designed the Sr-007 to have a lot of parasitic capacitance so the part of the diaphragm that makes sound can move more then other phones but that also calls for much more power to move them properly. Get the power right and no other headphone can beat the effortless control of the SR-007 even at extreme volume levels when the SR-? has long since turned into a mush of bass overhang.

Argh....!!! I've been found out!!!.... Now go ask Koji at EIFL for a quote as well as Japan might be cheaper.

You could always just go for something simple like a 80v zener at the input and then 3 stages.

Given the fact that Stax made some of the best SS amps in the world it would be worth a shot.

So you are going to skip a 10$ bias supply and go for a 1k$ amp instead?? I like it!!! It should be a fine match but the SR-Lambda loves the extra power the BH can give them though the GES should be quite nice with some MKP coupling caps.

Being a constant tinkerer is a way of life. It's not always for the better, that's for sure... If you going to angle the Lambda drivers even more then the stock design calls for you have to treat the housing a little and be very careful removing the drivers from the baffle.

After owning nearly every headphone there is there is nothing new and exciting. This is where my love of modding comes in so that there is something new to tinker with.

Here they are. First up is the Stax "A" design from the SR-3 instructions manual: Next is the SRX schematic from the same manual with the PSU: Here is the SRA-3S design: I think this is the SRA-12S or the 10S: This the rather smaller "Daughter of the Beast": Last but not least the whole 845 equipped "Beast". The schematic is so massive that the printing is a bit too coarse to fit it on the small page so the pictures are equally bad. If there is anything missing just ask me: Enjoy!!

The National design is a bit of a joke so it should be perfect for Ray. The schematics are uploading now and I've included both the 845 "Beast" design and the lesser "Daughter of the Beast" with a 6BX7 pulling output duty. I'll post them as soon as they are done uploading.

The tube Cad would be perfect for him and there is also that National circuit that can be used with both tubes and transistors for output duty. Two amps for the price of one... Here is the National PDF with the electrostatic amp at the back. I don't have a scanner but I can take a picture of it and the two other Stax schematics. I also have the SRA-12S here somewhere and the Jones designs. We might as well make it easy for Ray to steal some good designs...

I'm eagerly awaiting what crap Ray will come up with for his "reference" ESP amp. Milspec this and that... Good to that there is a solution to that particular problem. There is a large minimum order on the custom units though so that would make a small production run harder, right? The SRA-3S is fully DC-coupled but it uses output caps and it is a great little amp, with the emphasis on little as it is tiny! The SR-X was never put into production so that is clear but it was presented as a design for DIY use and it is all tubes but comes from the same era as the SRA-3S or the old Stax sound.