[TheAttorney]

Whilst searching the web for the UK retail price of the SR-009, I noticed, from one retailer's site, that the O2 price had increased a whopping £500 last week, from £1,495 to £1,995 - that's over 30%

.
 
The O2+energizer combo prices had also increased, but by just under 10%.
 
So, is this due to the ongoing rise of the Yen? Or a cynical attempt to minimise the impact of the high cost of the SR-009 - by hiking up the price of the lower model?
My guess is that it's a bit of both. Still don't know what the UK price of the  SR-009 is going to be.

 

[cascode]

Quote:

Originally Posted by trevorlane /img/forum/go_quote.gif
 
5 post n00b fail, soon he'll graduate to bashing beats and bose, so on and so forth.

 
What?

 

[MrGreen]

Anyone able to calculate electric field strength for your average stax phone? Alternatively, anyone able to give me a figure of the number of amperes/couloumbs running through it?

Amp output would be sufficient, I suppose.

 

[DaveBSC]

Quote:

This seems to be a minority orinion.Lots of members did and do utilize the old transformers and do like it better than mediocre direct drive amps.Maybe it's a question of perspective.What exactly is appropriate then? If the answer is T2 or even rarer/more expensive amps the SRDPro varieties  are not appropriate at all ......

 

None of the Stax transformers were never designed for anything near as power hungry as the O2. Same goes for nearly all of the Stax amps. Whether the GES is appropriate is the subject of some debate, some are quite happy with that combo. The Stax 717 is a perfectly capable amp, as is the "fixed" 727. The KGSS also works, and of course at the high end there's the BHSE and the WES. Nobody is saying that you need a T2 (although if you want to hear 100% of what the O2 is capable of... maybe you do). The SRD-7 just isn't going to do the job properly. Sloppy bass and etched treble is not how they sound at all with a good amp.
 

 

[cosmopragma]

Quote:

None of the Stax transformers were never designed for anything near as power hungry as the O2. Same goes for nearly all of the Stax amps.
 

Well,  the transformers themselves don't provide any power at all.They are passive devices.
Most of the loudspeaker amps that are utilized for the task in combination with transformers  do certainly provide way more power than any electrostatic headphones could ever swallow (and some are capable of driving very complex loads that are quite common in the loudspeaker world).
 
Quote:

The SRD-7 just isn't going to do the job properly. Sloppy bass and etched treble is not how they sound at all with a good amp.

Admittedly the coils of the old SRD7Pro transformers are a bit undersized for deepest bass but that's not much of a problem unless you are fond of special church organ music or some varieties of electronica.Most music doesn't contain substantial amounts of frequencies below 40 Hz anyway.
And again : etched treble is absolutely not characteristic for the transformer sound.That's a sign of a crappy loudspeaker amp or an age old transformer box desperately in need of a revision/renovation.
 
 
 

 
 

 

[spritzer]

The SRD-7 was indeed designed for the SR-5 and that part of the design never changed over the dozens or so versions out there. 
 
As for the amps, the ESP's are a reactive load just like all electrostatic speakers and many amps don't like that one bit.

 

[Clarkmc2]

Quote:

Well,  the transformers themselves don't provide any power at all.They are passive devices.
Most of the loudspeaker amps that are utilized for the task in combination with transformers  do certainly provide way more power than any electrostatic headphones could ever swallow (and some are capable of driving very complex loads that are quite common in the loudspeaker world).
 
Admittedly the coils of the old SRD7Pro transformers are a bit undersized for deepest bass but that's not much of a problem unless you are fond of special church organ music or some varieties of electronica.Most music doesn't contain substantial amounts of frequencies below 40 Hz anyway.
And again : etched treble is absolutely not characteristic for the transformer sound.That's a sign of a crappy loudspeaker amp or an age old transformer box desperately in need of a revision/renovation.

Total agreement, from personal experience. MY SRD-7s are modified with Spritzer's boards and rewired to a direct path from the inputs to the transformers and from them to the jacks. It is a great improvement, but even with the stock boxes great quality amps produced great quality sound. A small low watt amp of superior quality will sound better than a typical speaker amp. A hundred watts is total overkill. Five or ten perfect watts will amaze you. Don't worry about the numbers, just the quality of the electronics.
 
A little EL84 amp with a lot of iron will throw enough current into the transformer box to best almost any large amp sound wise.

 

[vrln]

 
Quote:

What?

No idea - to me it seems like some people overreacted to the "audio is a guy thing" comment. Which is entirely true, and I´m sure you´re not the only one here who finds it odd. Anyway, let us know how you like the Stax gear once you receive it! I wouldn´t even consider non-electrostats anymore. All dynamic headphones sound edgy and fatiguing after them, "digital" to use the common "audiophile term". Orthos on the other hand have no soundstage (at least the LCD-2 doesn´t).
 

 

[cascode]

Scanning through the posts here I've come across mention of a recommended mod to the SRM-727 amp.  I believe it is a change in 4 resistors, so I guess they are near the output and would be altering the bass rolloff.
 
Anyway, I can't find a specific post with instructions or description although I've searched the thread - anyone able to help?  A photo would be real nice

 
Cheers

 

[Gradofan2]

Quote:

Scanning through the posts here I've come across mention of a recommended mod to the SRM-727 amp.  I believe it is a change in 4 resistors, so I guess they are near the output and would be altering the bass rolloff.
 
Anyway, I can't find a specific post with instructions or description although I've searched the thread - anyone able to help?  A photo would be real nice

 
Cheers

 
PM me with your PM address, or email address, and I'll provide you the reference with pictures.
 
 

 

[cascode]

Quote:

 
PM me with your PM address, or email address, and I'll provide you the reference with pictures.

Many thanks - you got mail
 

 

[Knijsterbek]

I have performed the SRM-727 mod (4 resistors per channel) myself and I can really recommend it. I use it to drive the SR-007_MK2 and the SR-Sigma Pro (which also is difficult to drive) and I like the sound over an SRM-1 Mk2 and a SRM-t1. The latter I like with Sigma normal bias and Lambda normal bias.
 
If still needed, I can also provide details on the 727 mod.

 

[Gradofan2]

Quote:

I have performed the SRM-727 mod (4 resistors per channel) myself and I can really recommend it. I use it to drive the SR-007_MK2 and the SR-Sigma Pro (which also is difficult to drive) and I like the sound over an SRM-1 Mk2 and a SRM-t1. The latter I like with Sigma normal bias and Lambda normal bias.
 
If still needed, I can also provide details on the 727 mod.

That would be great - If you could provide a sufficiently detailed description of your mods - to allow others to complete them. 
 
Are they the same as Spritzer's mods - though, I think he just added 2 resistors per channel, and later suggested only 2 per channel were really required?
 
If you have pics available that would be great too. 
 
Or... if... you've documented this mods on another forum - perhaps you could just allow us to eMail you for the reference.
 

 

[Germs]

What is improved with that mod? From the information I found it improves the basses and the gain, anything else?
How much better is it, do we get something like Stax SRM-727 mod > 717 > 727 ?
I am also interested in any docs and pics to see how difficult it is.

 

[spritzer]

The mod simply extends the NFB line so that it includes the output stage and doesn't stop at the second to last stage.  When I did the mod I also raised the gain of the amp to match all the other Stax amps but I can't recommend that since it exposes a few gremlins.