The Headcase Stax thread

[Timb5881]

Just purchased a Stax SRM-1/MK-2 amp, with one side converted to a pro bias out put.  Seller say's everything is working ok, just a worn looking case.  I hope I like it with my SRX-3 MK III normal bias headphones.

[ktm]

On 4/25/2020 at 12:52 PM, Timb5881 said:

Just purchased a Stax SRM-1/MK-2 amp, with one side converted to a pro bias out put.  Seller say's everything is working ok, just a worn looking case.  I hope I like it with my SRX-3 MK III normal bias headphones.

Was that the one on EBAY for $150?

[Timb5881]

13 hours ago, ktm said:

Was that the one on EBAY for $150?

Yes, I was the only bidder.

[ktm]

I guess it's a good thing I didn't jump in. 😊

Hopefully the bias upgrade was done properly.

[Fitz]

What, not fighting to the death with your bare hands over a piece of gear you both were interested in? This isn't the Head-Case I know.

[ktm]

I reserve that energy for toilet paper purchasing.

[Timb5881]

Well it arrived yesterday.  I have a ground hum issue, my house unfortunately only has 2 prong no ground.  I am going to run a ground cable out the window and try and see if that works.  Low bias works ok, as does the pro.

[ktm]

If the plug isn't polarized, try flipping the plug.

[Hi-Fi-Anatomia]

Sorry about getting back here late

Here is the mk1 with the small plastic piece that goes over the solder pads.

[billqs]

That's pretty identical to what I have.

[bwck2000]

I have an es1a （omega clone ） loaner unit in US right now. I wonder anyone here would be interested to try them out ? Shoot me a pm if you do.

[Lord_Rexter]

Nice, could you share any links or pics 😁

[dripf]

If they're re-issuing it with a higher price tag I will take a dim view of the company.

[morphsci]

5 hours ago, dripf said:

If they're re-issuing it with EVEN MORE PROBLEMS, I will take a dim view of the company.

FTFY

[catscratch]

I hope they change the freaking headband. The 007 Mk2 is one of the few headphones I straight up cannot wear. The self-adjusting headband strap is too tight and keeps pulling them out of place, and there is absolutely no articulation on the earcups at all, so they're never exactly right. Since the 007 is so fit dependent, I have to pretty much hold the earcups in place. Yeah, the 007 still sounds very good (modded, tweaked, etc) but if you can't use it, what use is it?

Stax have a LOT of work ahead of them, and so far all we've seen is lackluster amps at twice the price they should be.

[dripf]

8 hours ago, morphsci said:

FTFY

Go over them again for me please.

I know they've reworked the cable relief and have had channel balance problems to an unknown extent. I'm going to be buying one so long as it doesn't get overpriced like the new 700 amplifiers.

[matthew-levi]

I am new to this forum, so if the question below have been answered, please bear with me, and help point me to the post.

I have an Stax Lamda and SRD 7 combination. Recently I opened up the SRD 7 to take a look inside and found the two transformers quite anaemic. I thought may be the performance of the SRD 7 could be better if we use a better transformer. I am using an Audio Research VS115 power amp to drive it.  Looking the schematic, it looks look the transformers are like tube output transformers. Does anyone have any idea about what spec those transformer would be like, primary impedance (facing the loudspeaker output from the amp) vs secondary impedance (facing the stators). Would a 10K : 8ohm push pull output transformer be suitable for this, just want to experiment.  Any advice would be appreciated.

[Angst]

19 hours ago, matthew-levi said:

I thought may be the performance of the SRD 7 could be better if we use a better transformer.

You can find a SRD-7 schematic here. More than anything they are isolation transformers because the energizer needs to have a 230 volt DC bias on the headphone side. Your driving amp modulates the audio signal on top of this. The transformer is likely fairly high impedance, and unity gain. You can see in the schematic that Stax put a 27 ohm power resistor load across each primary for amplifier compatibility.

Beware of the high voltages, you play with this at your own risk and the voltages are potentially lethal.

[matthew-levi]

The transformers in SRD 7 are not isolation transformers. I have measured the input voltage (from the amplifier loudspeaker terminal) and the SRD 7 transformer output voltage to the earphone. I put a 1Khz 1 volt input into the transformer and the output is about 36 volts. So its a step up transformer. 

[Zoide]

On 4/7/2019 at 10:55 AM, spritzer said:

Also sunshine is ultimate enemy of electrostatics as it breaks down the diaphragms over time. 

That's pretty scary. Why doesn't STAX release a dark version of the dust cover? I thought I was fully protecting my L700 with the official transparent cover, but I guess I'm going to have to throw a dark t-shirt over them or something 😅

[Pirx]

In my opinion the direct sun light means direct UV that is degrading many materials.

I think that plastic dust cover is not transparent for UV and it means you shouldn't worry about it.

But probably more dangerous is heat  from sun light. If you do not have windows with infrared filters on the glass (for example I have), it is better to place Stax in the shadow.

[padam]

1 hour ago, Katyusha said:

Do people here still think the SR-007MK1 is better than the current 007MK2.9?

"Better" is a relative term, each has its advantages and disadvantages.
There are several SR007Mk1 variations (70xxx with the carbon box, 71xxx, SZ1) and it is probably very hard to find a 'golden' sample now, because why would anyone sell such a headphone, unless he is completely unaware of the differences and happen to accidentally own such a pair. And without comparing two SR007 headphones side-by-side(maybe new pads on both and a properly seating headband, since both may also affect the sound), it may be difficult to evaluate it.
So for practical purposes, the Mk2.9 should be a better, safer option.

Edited June 6, 2020 by padam

[Zoide]

What's the final word on the L700 MK2? Are they sonically different/better than the L700, or just the same earspeakers with better materials? The Minidisc video review says there can be minor differences due to a higher clamping pressure, but other than that there are very few comparisons online.

I might get a chance to buy an MK2 and sell my MK1, but I'd like to know if it's worth the hassle.

Thanks

[Lord_Rexter]

These are my subjective impressions. 

My chain Mac Book pro - > Denafrips Ares II - > KGsshv dual outputs (both L700 OG and L700 Mk II connected) 

L700 Mk II have tighter bass the reason could be due to angled metal forks giving it tab better clamping force and the may be the new cable might have something to do with it as well. L700 MK II is sharper and little more efficient than the L700 OG. Little better detail retrieval as well (I could be wrong as well). 

Hope this helps. 

[Zoide]

8 minutes ago, Lord_Rexter said:

These are my subjective impressions. 

My chain Mac Book pro - > Denafrips Ares II - > KGsshv dual outputs (both L700 OG and L700 Mk II connected) 

L700 Mk II have tighter bass the reason could be due to angled metal forks giving it tab better clamping force and the may be the new cable might have something to do with it as well. L700 MK II is sharper and little more efficient than the L700 OG. Little better detail retrieval as well (I could be wrong as well). 

Hope this helps. 

Interesting. What do you mean when you say the Mk II is "sharper"? How come you're keeping both?

Thanks!