The Stax thread (New)

[mirumu]

Originally Posted by derekbmn

Wow,the numbers are much lower than expected. I guess that I (and possibly others) were thinking the numbers on the KGSS(700v), KGBH(800v), ES-1(800v) ,etc WERE the RMS values. Are you sure the STAX amps are truely rated with the RMS value ??

For me there's one of those lines that stands out especially...

Originally Posted by spritzer

SRM-T2 630v

[mirumu]

Originally Posted by humanflyz

You and Carl both provided some very good information, but it hasn't helped me decide lol, which is a good thing I guess: more choices. I would've been happy with an O2+KGSS combo since I've heard that combo before and like it. But you know what they say: can't leave well enough alone, just had to be curious about the 4070, which receives very very little attention. But it seems to be picking up, as I've heard from both you and Carl, Gordie, and Wmcmanus have chimed in. What piqued my curiosity was that Gordie, who is a big fan of the K1000s, likes them a lot. And Wmcmanus wrote last night that in some areas, the 4070s might even have an edge over the Orpheus.

I definitely think the 4070 deserves more attention than it gets. I bought the O2 without even hearing it once since in this part of the world there seems to be few ways to audition anything in that league. I was convinced from everything I read (and my experiences with the HE60, SR-003 and SR-X Mk3) that I'd like them and thankfully they exceeded my expectations. With the 4070 being generally more scarce worldwide I think many more people are in the same position as I was with the O2 of having to take the risk of buying the 4070s without an audition. Personally I do think they're worth a try, especially for those who like electrostatics. I do hope a few more take the chance on them, I think they may be pleasantly surprised.

[spritzer]

Originally Posted by Carl

Wow, incredible list. I didn't realise the KGBH put out so little power, I always thought those things gave over 1kVrms. Thanks for the info!

Do you remember how much the SRA-4s, SRA-6s, SRA-7s and SRA-10s deliver?

It can deliver 1060v but the 600v or so volts is the nominal figure but I'm not sure. It isn't clear with some amps if it is peak power or nominal so I put in the lower figure.

All of the older integrated amps have a similar output voltage but where I couldn't find a definitive number I left it out.

Originally Posted by edstrelow

I see that Spritzer is an advocate of running these from a tranformer and large power amp. This may work, but I don't like tying up an amp that way. You would need to connect your speakers to the terminals on the transformer and that is not going to be good for the speakers.

I have just been listening to Sigma pros through a SRM-3, amp, the precursor of the current 313 and it is pretty effective. I would pay attention to power however, since these phones are less efficient than the Lambdas with which they were later replaced with by Stax. Some fairly cheap tweaks to get more power from your amps are: 1) use an upgraded power cord; 2) plug the amp directly into the wall, rather than use a power strip for them; 3) use a contact enhancer on all plugs, pin and IC's. I have used Progold over the years but am more now impressed by Mapleshades' Silclear, a silver-based product.

The STax 717 is significantly more powerful than the SRM-3 or 313 but also a lot more expensive. There are numerous other aftermarket amps now available.

I'm not advocating the transformers as a reference amp but if you are on a budget and you have some hard too drive phones this is the way to go. I've here on hand the 313, T1 and the Blue Hawaii and only the Blue Hawaii can drive the Sigmas to reach their full potential. The transformers can wake them up much more then either of the Stax amps can.

Originally Posted by jigster

So Rudistor's stax amp should be quite ideal to drive the O2s? But they don't seemed to be favoured. I wonder why? Their amps do look gorgeous albeit not as compared to the ES-1 IMHO

For me it is a bad design and they are cheaply built. The cases he uses for his reference amps are the same ones I used for the KGSS amps I built back in the day and they are the worst I've ever come accross.

Originally Posted by derekbmn

Wow,the numbers are much lower than expected. I guess that I (and possibly others) were thinking the numbers on the KGSS(700v), KGBH(800v), ES-1(800v) ,etc WERE the RMS values. Are you sure the STAX amps are truely rated with the RMS value ??

There is nominal output and there is peak output. It isn't always clear which is which but I thought it would be great to asemble a single list so we can finally get this straight.

Stax uses RMS for their amps and it is peak power at 1Khz

[bralk]

Originally Posted by mirumu

This is why in my opinion the need for isolation is the main factor I would use to guide a buying decision between these two.

Thanks for your detailed comparison. Could you comment on the differences in
comfort. Pressure on the ears etc.. ?

Kind regards

Tom

[mirumu]

Originally Posted by bralk

Thanks for your detailed comparison. Could you comment on the differences in
comfort. Pressure on the ears etc.. ?

Kind regards

Tom

Both of them go around the ears so there is no pressure on the ears themselves. To me the O2s with their rotating pads and headband are very comfortable. Being able to rotate the cables out of the way no matter how you're sitting is nice too. The main complaint people seem to have with the O2s is the heat but personally I don't find this to be an issue. The 4070s headband design is very similar to the O2s but of course the pad design is substantially different. The main difference to me is that the 4070 driver housing is quite weighty and long but I feel the headband does a good job of spreading the weight as best it can. It also gets quite warm around the ears although not quite as much as the O2s which form more of a closed seal around your ear. I find both comfortable for long term wear. The only things with the 4070 that bothered me at all were related to the long weighty driver housing. I'm just average build, 5'7" and the cables coming out the bottom were just a little above the shoulder which could make sitting with them awkward in some postitions. When I tried to lie back with them gravity would try to pull them off my ears.

[Carl]

Originally Posted by bralk

Thanks for your detailed comparison. Could you comment on the differences in
comfort. Pressure on the ears etc.. ?

Kind regards

Tom

The 4070 is a heavy headphone but has nothing on the torture devices made back in the 60s and 70s. The O2 is what you'd expect from a modern open-circumaural headphone; comfortable.

[Downrange]

Originally Posted by Carl

The 4070 is a heavy headphone but has nothing on the torture devices made back in the 60s and 70s. The O2 is what you'd expect from a modern open-circumaural headphone; comfortable.

My O2s are very comfy. My ears get slightly warm, but not a problem. The Lambdas are slightly more comfortable to me. Haven't tried the 4070s yet, but still remember my first decent pair of headphones - Koss Pro-4AA I bought back in the early seventies. They really weren't too bad for their time, with liquid-filled cushions that really sealed out sound well.

[Don Quichotte]

Sorry if this question has already been addressed, but has any consensus been reached regarding the issue of Stax playing music off the head?

[spritzer]

Originally Posted by Don Quichotte

Sorry if this question has already been addressed, but has any consensus been reached regarding the issue of Stax playing music off the head?

I don't see any reason why they shouldn't be fine. The mylar won't stretch because it has more air to move. Mylar is extremely tough material and there isn't enough force inside the driver to do any damage. I've put a force equal to 4kg weights hanging off a piece of mylar in all directions and the drivers are still going strong after two years even though they are a bit light in the bass...

In the Sigma manual Stax suggested that they could be used as mini speakers when mounted on their stand and playing against a wall.

[smeggy]

I just saw a 313 in ebay.de using one of my pics. Damn nice photo though, captures my deckchair leg wonderfully

[bralk]

Originally Posted by mirumu

The main difference to me is that the 4070 driver housing is quite weighty and long but I feel the headband does a good job of spreading the weight as best it can. It also gets quite warm around the ears although not quite as much as the O2s which form more of a closed seal around your ear. I find both comfortable for long term wear.

Thanks for clearing that up for me. I am using O2s, but find them less comfortable than than my previous Lambdas. I am very satisfied with the audio quality from the O2s and guess that I won´t find better (but different) audio quality from the 4070s and also a different (but nor better) wearing comfort.

Kind regards

Tom

[jigster]

Sanders ESL Amp
http://www.sanderssoundsystems.com/ESL%20Amplifier.htm

Wonder if using this via the energiser would be good.

[audiod]

Originally Posted by jigster

Sanders ESL Amp
http://www.sanderssoundsystems.com/ESL%20Amplifier.htm

Wonder if using this via the energiser would be good.

Sounds like a great amp for driving Martin-Logan CLS's or Sound Lab A-1's, but a bit much for driving headphones. Sometimes when you use a amp at a small fraction of it's potential (relating more to solid state amps) you are not getting the best performance from the amp. I have not heard these amps so this is just a educated guess. I have read many articles by Roger Sanders over the years on electrostatic loudspeaker design. He does know what he is doing. I don't think he had driving electrostatic headphones in mind when he designed these amps. Maybe we should contact him and ask for a dedicated electrostatic headphone amp!

AudioD

[Carl]

50V/ms seems a little on the slow side for electrostats.

[Carl]

http://page6.auctions.yahoo.co.jp/jp/auction/f56245095