spritzer

Let's just say I have a personal museum...

Yes, dual concentric volume control on this one and I'm pretty sure this was the first balanced Stax amp.

Now for something pretty rare... the ESP900... This is the closed back version of the ESP950 made for medical use such as MRI's etc. Not much is known about these and only a few sets have ever surfaced. I'll do a more indepth post about these when I modify them and dig into them a bit. Stock...well...they don't sound good. The earpads are unique to these so when you press them to the head...the sound gets better but it is no 4070...that's for sure.

Now time for something super rare... a balanced SRM-1 Mk2 PP. I didn't think any of these existed as there was the ATR version for studio use which had a stepped attenuator and balanced inputs but in almost 20 years of searching...none have turned up. Then I came across this one last year in Japan in pretty rough shape with tape all over it. I naturally over payed as usual but then again, how often does one find something like this: So years ago I did this and nice to see Stax did the exact same mod as me. Remove the 100R resistor to ground on the other side of the fet and put two resistors off the board in its place. The amp also arrived with one channel dead, shorted transistors and almost open resistors in the front end. Now for the money shot... This is clearly stock from Stax as all the screws match what they used at the time but one odd thing is that the markings are actually engraved into the back and not simply silk screened.

They are quite a bit better than my Massdrop unit sitting here. It's not stock though so angled leather earpads and a Stax Wide PC-OCC cable plus most of the damping in the earcups has been removed. The whole sound from the RR1 is tighter and more focused while the ESP is warmer and slightly softer. It does remind me that I need to post about something in the ESP thread... They do share one thing in common though, squealing. Now the RR1 has dust covers but the left driver on this set has been noisy from the start. It comes and goes and right now it is absolutely silent. The right one has always been silent though.

23 seconds... any longer and you will ruin any headphones!!!

I felt like that back in the day getting into my friends BMW Z3 M...fuck that car was tiny...

This has been a killer of a week for me so I'm late with the impressions. Then all of sudden we had a holiday today so I finally have some free time. I'm too lazy to find my camera so I'll take some pics later. First off, this is set nr.4 so I very much view it as a "work in progress" but...they are pretty awesome. From the first impressions and until now they keep reminding me of the SR-007. Clearly power hogs (I measured the system with stock cable at 160pf) too and a bit dark sounding. Now in my book this is a welcome reprise from all the bright models out there now. Doesn't mean the treble is subdued or anything like that, it is just not as apparent as with the L700 or 009's for instance. This also gives it a fuller sound and well...that bass. The cups are ported so the bass could have been compromised due to that but not so here, it's deep, tight and tuneful. It doesn't match a closed SR-007 but I frankly don't mind that...I can always grab my 007's if I want to listen to them. These are a bit more tuneful with more presence higher up. One of the first tracks I tried on them is the one which 009, 009S and 009BK all fail miserably at, but no issues here. They replicate the snare drum perfectly and same goes for everything else I've thrown at them. The midrange is perfectly fine and really showcases the difference in mastering on some tracks. The soundstage is just about perfect, follows what the tracks should sound like and doesn't pull a HE90 on us. Not quite up to the layering of the 007's but then again...that is the gold standard. Overall they are very neutral and do what any transducer should do, get out of the way. For me the biggest compliment to any headphones is me willing to listen to them as well, I have a lot of headphones at hand. I've used these almost exclusively since I got them, only swapping out to do comparisons. Now for fit and finish, I have no complaints. The headband is very sturdy with nice spring steel for the main span and they fit my head nicely. A bit snug but then again, I have a melon for a head. I did bend the arc a bit and now I can use them for hours at a time. The housing is attached to the earcups with a single M4 bolt and I did experience some rubbing there. This joint wasn't really supposed to move but for my use, they fit better that way so I place a nylon washer between the two parts and that has fixed this. I've already relayed this to Aumkar who should be arriving back home soon. The only major issue I've had is with the cable or rather one of the connectors. One channel started to drop out and after some troubleshooting this was traced to the mini XLR plug. I bought some new ones and made a quick replacement cable this morning and now it works perfectly. To keep the cost down the mini XLR does work for this but yeah... I'd like something better but given the cost constraints I get why they use it. Same for the cable, getting anything which works for this is difficult and costly. The cable is still better than what Hifiman are using so yeah... I'm not too worried about that. So over all, I'm very, very impressed and I will be working with Aumkar to see if we can't improve on these small issues.

It was awesome meeting you and getting the headphones hand-delivered. My impressions will be coming soon but a small sneak preview after a very limited time with them (aka I couldn't help myself), don't let the price fool you to think these are budget headphones...they don't sound like that.

Indeed and the basis for one of the most expensive electrostatic amps...the MSB

I never found any way to properly fix them. Changing the pads made some minor changes but I just gave up and moved on. It would be worth it for the Black Gates alone and easy enough to fix.

Looks brilliant!! ...so when can I order one?

I don't have a soft spot for what was a compromise from the start. The chassis they ended up with was not what they wanted to do as the tubes were supposed to be in chimneys to take away a lot of the heat but it was probably too expensive. The stuff on the input tubes are shields to try and keep crap out of them. They used nice caps but no audiophile BS.

It's a feature that it can cook eggs on the top panel... Kinda funny when the only option in Iceland is to take off the top panel and have a fan close by to cool it.

I sold it back in 2010 as it makes no sense to keep it. It doesn't sound as good as people think it does and the hum bothered me a lot. Well that and it was doomed to fail so I just recapped it and moved it on.

Done and some nostalgia as it's been a decade since this was going on...

If those resistors blow, there has to be a short in the output stage. See the schematic:

I will be getting a set as well. The L700's have potential but this is modern Stax so fuckup is a 50/50 tossup...

I'd start there but it might be a good idea to go even lower.

That does look like a nice solution for a detachable cable but they did say somewhere it was the first time... ehhh no... SR-Omega...

Well you need to look at the system as a whole and HE90's at pro bias is a really, really bad idea. Ideally you should go even lower down than 500V as the D/S gap in them is so small. Well that and uneven stators but that's a known issue. So with the HEV90, the max voltage swing is just about 1100Vppss on a good day so they can get away with that. Now plug this into a Carbon or a T2 and... well... that's not a good idea really. It is so easy for the amps to overdrive the headphones so I'd personally scale down the bias even further.

I never messed with the earpads on the ECR-500 as it was really before all that started....

60-70$ or so. Not bad for the quality you get.

You can also just use the extension cable that came in the box. Also the angled earpads were a custom order from Vesper Audio. Fong carries the normal flat pads but it is easy enough to order the custom ones from Belarus.

I prefer the newer 007 pads and they last a lot longer than the old ones.