[soren_brix]

  Pulled the trigger and just ordered the SR-007 MK2, I looked over many impressions and I'm taking the plunge.  I was struggling with either the 007 or 009 but I decided to go with the 007.  Wish me luck.  PS.  Been a long time since I posted!  Let me just say I have no intentions of ordering a 5 - 10k amp for it.  Gonna use what I have been using and see what I think.  Good to see this community is still thriving.

...so not happy about the 007's?

 

[astrostar59]

  ...so not happy about the 007's?

Ehh, it that really old that post? Anyway, I like the 007A but not the older MK2/2.5. I can't say so much on the MK1 as never owned that.
 
IMO the current 007A is damb good, slays the older Mk2 versions for sure. If you think it is less the half the cost of the 009, then a bargain in it's way.
 
It is also more forgiving with sources / brighter recordings,

 

[soren_brix]

 
Ehh, it that really old that post? Anyway, I like the 007A but not the older MK2/2.5. I can't say so much on the MK1 as never owned that.
 
IMO the current 007A is damb good, slays the older Mk2 versions for sure. If you think it is less the half the cost of the 009, then a bargain in it's way.
 
It is also more forgiving with sources / brighter recordings,

just wish you had mention this earlier on ...

 

[astrostar59]

  just wish you had mention this earlier on ...

I don't understand. Pretty much everyone agrees the 007 is more forgiving than the 009. However the 009 is the better headphone if it has a good front end and a good amplifier to drive it. This is pretty much how speakers are actually. A simple 2 way speaker is more forgiving, but a more advanced and higher quality speaker will reveal a lot more of what the source is doing, which in the case of a lesser front end is not good news, but a better front end and it will sound incredible.
 
So there we have the audiophile dilemma, do we buy amazing headphones and skimp on the rest of the system? I would say no as it doesn't work out.

 

[lilbthebasedgod]

   
Excellent impressions, mirrors my opinions (although not completely fair, from what I've gathered the SRM-3 is not nearly as good as the SRM-1 Mk2)

Yeah, that's what I was thinking.  I don't think the 404LE is particularly hard to drive at all, so I doubt it would make up all the difference, but it might some.

 

[joseph69]

I received a Mjolnir KGST this morning  from the F/S forums until my BHSE arrives, and I must say I'm enjoying the combo very much!

 

[edstrelow]

Excellent impressions, mirrors my opinions (although not completely fair, from what I've gathered the SRM-3 is not nearly as good as the SRM-1 Mk2)

I have both and generally agree. The key advantage of the Srm1Mk 2 is higher voltage swing, 370 volts Vs 300 for the Srm3. This translates into better dynamics.

 

[martyn73]

I've just got a SR-007A - what's the best amplifier from Stax? I've got a SRM-006t but have read postings which suggest that it's not a good pairing with the SR-007A. Does the SRM-353X produce more voltage, albeit without the typical valve sound? I cannot stand sibilance so prefer a warmer sound. Unfortunately, exotic amplifiers and Stax's own SRM-727 are not an option. I read a review on Innerfidelity which was critical of the SRM-007.
 
So far, the SR-007A has more bass impact than the SR-L700 and SR-404LE, but I'm not entirely sure whether a solid state SRM-353X is suitable. Any advice most welcome.

 

[Rhamnetin]

  I've just got a SR-007A - what's the best amplifier from Stax? I've got a SRM-006t but have read postings which suggest that it's not a good pairing with the SR-007A. Does the SRM-353X produce more voltage, albeit without the typical valve sound? I cannot stand sibilance so prefer a warmer sound. Unfortunately, exotic amplifiers and Stax's own SRM-727 are not an option. I read a review on Innerfidelity which was critical of the SRM-007.
 
So far, the SR-007A has more bass impact than the SR-L700 and SR-404LE, but I'm not entirely sure whether a solid state SRM-353X is suitable. Any advice most welcome.

 
The SRM-353X is said to be the best out of the box Stax amp, followed by the SRM-323S.  Both have the most power if I recall correctly which is great for the SR-007.

 

[martyn73]

   
The SRM-353X is said to be the best out of the box Stax amp, followed by the SRM-323S.  Both have the most power if I recall correctly which is great for the SR-007.

I wonder if it's better to apply EQ to slightly reduce treble using a parametric equalizer or use a valve/valve hybrid amplifier.

 

[Michgelsen]

   
The SRM-353X is said to be the best out of the box Stax amp, followed by the SRM-323S.  Both have the most power if I recall correctly which is great for the SR-007.

 
No, the 717 and 727 have the most power of all Stax common amps (which does not include the T2 of course). However, the 727 needs to have the feedback mod applied to sound best, and that's why you do not often see it recommended as best 'out-of-the-box' Stax amp. 717 sounds great though if you can find one second hand.

 

[DolphinG]

 
Received SR-L700 from local distributor yesterday.
Compared it with SR-009 and SR-507 for several hours. (with SRM-300)
More comfortable and neutral than SR-507. (But I also like SR-507 sound)
I think that it can be compared to Nova Lambdas, and closer to SR-009 sound than other lambdas.
Checked if metal case-holder of SR-507 works on SR-L700, and found that it fits very well.
But opposite does not work as hinge of SR-L700 case-holder is a little bit longer than that of SR-507.
I like SRM-300 but should test it with SRM-727A and SRM-252S.

 

[soren_brix]

  I've just got a SR-007A - what's the best amplifier from Stax? I've got a SRM-006t but have read postings which suggest that it's not a good pairing with the SR-007A. Does the SRM-353X produce more voltage, albeit without the typical valve sound? I cannot stand sibilance so prefer a warmer sound. Unfortunately, exotic amplifiers and Stax's own SRM-727 are not an option. I read a review on Innerfidelity which was critical of the SRM-007.
 
So far, the SR-007A has more bass impact than the SR-L700 and SR-404LE, but I'm not entirely sure whether a solid state SRM-353X is suitable. Any advice most welcome.

 

Originally Posted by Kevin Gilmore  /img/forum/go_quote.gif
 
The 727 is a local feedback version of the 717. The 727 has a current source, the 717 has a resistor. Otherwise virtually identical.
The 727 runs the output stage at higher power.
 
The kgss and the 717 are similar amplifiers. (4 stage amplifiers)
 
The kgsshv and the 727 are similar amplifiers except the kgsshv uses global feedback. (4 stage amplifiers)
 
If people want it, the next revision of the kgsshv boards will have the local/global feedback option. [which it has]
 
Personally i like the sound of the global feedback version better.
 
The 313 and 323 are 3 stage amplifiers. Same or similar to all the transportables (srmXh,srm151,srm252)
 
There are the 2 ac coupled single power supply amps, sr-001 and srm300
 
the srm-t1, t1s and 006t are virtually identical. (solid state/tube hybrid)
 
the 007 has twice the number of output tubes and runs the output stage at twice the power. (solid state/tube hybrid)
 
The T2 is a tube/solid state/tube hybrid.
 
The BH and BHSE are essentially the T2 output stage with the kgss input stage configured for 800 volts.
 
For stuff older than the srm-t1, things get complicated. spritzer has more of the really old schematics.

 
So far, no hard evidence that a 353x is more than a 323s/313 with added balanced input.
To drive your 007's you probably need 717/727/KGSS/KGSShv ...

 

 

[martyn73]

   
No, the 717 and 727 have the most power of all Stax common amps (which does not include the T2 of course). However, the 727 needs to have the feedback mod applied to sound best, and that's why you do not often see it recommended as best 'out-of-the-box' Stax amp. 717 sounds great though if you can find one second hand.

The SRM-727 has a power rating of 450V r.m.s./1kHz compared with 400V r.m.s/1kHz for the SRM-353X and 300V for the SRM-006t, but I don't really understand voltage swing.

 

[Michgelsen]

The larger the voltage swing, the louder the headphones can go. This isn't very useful by itself, but simply put: the larger the reserves of an amp, the better it can control the headphones during the extremes of the music. That's why more powerful amps have better dynamics and control, and have more headroom before they start clipping in loud passages such as bass beats.
 
Voltage swing can be quoted in different forms, such as RMS (root mean square) or p.p. (peak to peak) or in yet other ways. You can't compare these directly, but you can convert between them.
 
Electrostatic headphones mainly require voltage to work, and barely any amperes (current). Obviously, there must still be a small current, but I do not know how these relate to amp or headphone performance.