[ericj]

it's an outboard supply? 
 
now i believe you even less. 

 

[miceblue]

it's an outboard supply? 

now i believe you even less. 

Well unless you've heard it yourself, I don't think you'd understand.

I have the 252S, replacing the wall wart with a fully regulated supply improves the performance when driving the SR-Lambda series(207,307,407,507) and the Sennheiser HE-60. It will drive the SR-009 if the volume is not turned up too high.

1) Yes because Japan's households operate at 100 V whereas in the USA it's 120-130 V. I use a Kashimura TI-101 step-down tansformer.

Oh man, I really like this little box over my TI-101.

It has some power conditioning in there and I really like how it affects the sound (blacker background, smoother sound, more dynamic).

A friend of mine gave it to me while cleaning out the apartment and I'm not sure what modifications there are since the outlet looks replaced.

Oh, you were originally just talking about the wall wart. My bad. I don't know if it makes a difference between 120 VAC and 100 VAC. I don't want to risk blowing up anything though.

 

[gefski]

it's an outboard supply? 

now i believe you even less. 

Are you suggesting outboard power supplies per se are not good?

Or just specific power supplies for Stax?

 

[ericj]

Are you suggesting outboard power supplies per se are not good?

Or just specific power supplies for Stax?

 
I'm suggesting that wallwarts necessarily have a very limited impact on the sq of devices that have internal switching power supplies. 

 

[b0bb]

   
I'm suggesting that wallwarts necessarily have a very limited impact on the sq of devices that have internal switching power supplies. 

The SRM 252s does not have an internal switching supply, it is an unregulated voltage multiplier, and this is why they took extra steps like swapping the polarity on the power input pin which blows the fuse when a normal wallwart is plugged in.
 
Below is a picture of my 252s which I modded

 
The IC in between the white words is a switched mode controller but STAX used it as a free running squarewave oscillator, the transformer steps up the 12V pulses 12X to 144V and the diode capacitor charge  pump on the secondary side doubles it to 280V
 
There is no voltage feedback to the controller from the HV side, it is not regulated.
 
As a quick test I increased the DC input from 12V to 15V, half expecting the switching duty cycle to change to correct for the change, nothing happened and the high voltage side went up from 285V to 325V
 
It is a pretty strange way of doing things....

 

[Chris J]

I really doubt that the power supply voltage makes a difference. Usually the internal voltages are zener referenced.

Do not advise someone to run a 100 Vac power supply off 120 Vac!

 

[TsukiNick]

Well unless you've heard it yourself, I don't think you'd understand.

Oh, you were originally just talking about the wall wart. My bad. I don't know if it makes a difference between 120 VAC and 100 VAC. I don't want to risk blowing up anything though.

Japan is pretty weird and use 50hz on one side of the country and 60hz on the other, it caused problems during the Earthquakes because they couldn't easily distribute power without converting it.  Some things run fine on the opposite power standard and things especially like heat producing devices (Hair Dryer, Kotatsu) will run into problems.  I would never recommend using something with the wrong power type unless the manufacturer says there will be no problems.

 

[Rozenberg]

Now I hope someone would give me answer...

I got an offer to buy SR-202 for 245€ shipped plus 1 year warranty since I don't the SRM-212 that comes with it (price is 425€ as a set).

Good price or not? As for amp, I'm looking for SRM-1 mk2 separately.

 

[west93600]

Hi,

What do you think about the Stax SR gamma pro ?

Thank you by advance.

Nobody can answer me please ?

 

[ericj]

Most stax heads seem to think that the best use for a gamma pro is to use the drivers and cable to make an sr-x pro.

.:Sent by pneumatic tubes

 

[Ali-Pacha]

I own both of them : original Gamma Pro (not so common) and original SR-X/mk3 Pro (true unobtainium)
Soundwise, SR-X/mk3 Pro are not way above or below. Same driver, different enclosures, different sounds.
Major differences are soundstage and FR signature. Gammas are airier / larger, and their FR are less flat, with something foot-tapping you don't have with the full honesty of SR-X. The latter are a bit more meaty in the very low-end, too.
Anyway, SR-X/mk3 Pro are very (very) rare...that could explain the market for DIY SR-X/mk3 Pro (normal bias enclosure + cable/driver from Gamma's).
 
Ali

 

[ledzep]

Anyone had any experience of upgrading the headspeaker cable on the 2170 set up

 

[ledzep]

You can use any appropriately rated wall wart, but you might have to reverse polarity of the output. You can do that by either rewiring it yourself, or buy on that have output plug which allows you to do that.

 

[n3rdling]

Anyone had any experience of upgrading the headspeaker cable on the 2170 set up

 
They're not meant to be replaced with anything but Stax cables.  These are specially made low capacitance, high voltage cables.  Using a normal wire would just make the headphones harder to drive for the amp.

 

[ericj]

   
They're not meant to be replaced with anything but Stax cables.  These are specially made low capacitance, high voltage cables.  Using a normal wire would just make the headphones harder to drive for the amp.

 
 
The high voltage aspect of the cable is not really that big of a deal. At least, it's not hard to find wire with a 1kv rating or higher. I am pretty sure that it's just pvc insulation plus the rubber. 
 
The low capacitance aspect is mainly due to it being a flat cable. Some Stax came with special even lower capacitance cable that has a wider row of insulation between the wires. 
 
If you think about it, if you bought some good wire, and perhaps some hollow tubing to use as a spacer between wires, you could use a weaving loom to make a cloth-jacketed stax cable. 
 
This is a craft project i have not engaged in. 
 
fwiw, Spritzer used to go on and on about low capacitance wire insulation, and rail against the concept of PTFE (teflon) insulation as being too high capacitance. I'm not convinced that he wasn't smoking something because he also claimed air to be the best insulator, which is far from true. Air is an OK dielectric, but there are far better ones out there.