Just bought Stax SR-009 (arrggg) but no amp

[spritzer]

I'm way too lazy to do another DIY chassis at this point but I think some DHT action is in my future.  I'll at least order up the remaining parts for this 300B amp.  Good to use some of these filmcaps too... 

[Jon L]

I'll at least order up the remaining parts for this 300B amp.  Good to use some of these filmcaps too... 

 

Of the numerous 300B amps I've listened to, only couple of them sounded very good to me, so lots of circuit/ implementation hurdles to make a truly great 300B amp.  I did enjoy my time with the superb AVVT AV32B, but only in a "normal" 300B op points.  I wish somebody would design an amp around AV32B with its 65 watt max plate dissipation   Oh, and drive them with something other than the 6SN7 

 

AVVT32B by drjlo2, on Flickr

Edited October 5, 2013 by Jon L

[spritzer]

The first trouble with a 300B amp is running it single ended through a transformer.  So we can improve performance by using a simpler transformer.  Also better drivers help but I'd still use a large number of tube besides the 300B...

[justin]

 

 

Oh, and drive them with something other than the 6SN7 

but i already have a whole closet of 6SN7!

[spritzer]

Get them out of the closet!!!!  

[cetoole]

I'd still use a large number of tube besides the 300B...

Oh?  Like?  Have a pair of 3k:8r OPTs calling for a home.  Been thinking triode strapped 6688-300B.

Edited October 5, 2013 by cetoole

[dsavitsk]

Oh?  Like?  Have a pair of 3k:8r OPTs calling for a home.  Been thinking triode strapped 6688-300B.

 

300B is hard to drive well. How about putting a follower between the driver and the 300B.

 

I have always been drawn to the eletraprintish* design of a low-to-mid power op amp (like 5-10w) driving a 32:600ohm transformer feeding the grid of a DHT tube. 

 

I am biased towards push-pull so 2 DHTs in my case, but to each his own. 

 

* If this is not an electraprint design I am sorry and welcome correction. 

 

Jack has done such things. I think you can do a better circuit than the opamp as driver, but it is a quick and easy solution. The biggest hurdle is the step up transformer as it will need a sizable core (or a ton of windings) to deal with the voltage swing. Something like a Lundahl LL1689 would work. The 119DA might. If Hammond's rating is to be believed it should swing  80V or so.  The voltage gain is low, so maybe pair it with a 1:4 step up before the driver circuit.

[dsavitsk]

I wish somebody would cover the cost to design an amp around AV32B with its 65 watt max plate dissipation 

 

FTFY

[cetoole]

300B is hard to drive well. How about putting a follower between the driver and the 300B.

If the 6688 can't drive it with an rp of 3.4k triode connected, I would be more likely to use a d3a or something.

[dsavitsk]

It can drive it, and it will probably work fine. But since when is fine good enough?

 

I'd actually be inclined to use it in pentode mode ...

[Jon L]

Stax SR009 1 by drjlo1, on Flickr

 

My very own SR009 just arrived, as beautiful as ever.  

 

Although I already knew it, switching between SR007 MkI and SR009 in real time, I am severely struck by the fact there is NO way one system could be optimized for both 'stats.  If using the same amp, at least some tube and cable swapping must follow in order to enjoy both.  Now I wish for 'stats that combine the strengths of SR007 and SR009...maybe stick those SR009 drivers into nice warm wooden cups, but who'd be Krazee enough to do something like that 

[spritzer]

Oh?  Like?  Have a pair of 3k:8r OPTs calling for a home.  Been thinking triode strapped 6688-300B.

 

The EML tubes in an octal base for DHT's but there are some very good triode strapped pentodes out there.  I do have a fondness for odd tubes nobody uses though...   

[padam]

 

Stax SR009 1 by drjlo1, on Flickr

 

My very own SR009 just arrived, as beautiful as ever.  

 

Although I already knew it, switching between SR007 MkI and SR009 in real time, I am severely struck by the fact there is NO way one system could be optimized for both 'stats.  If using the same amp, at least some tube and cable swapping must follow in order to enjoy both.  Now I wish for 'stats that combine the strengths of SR007 and SR009...maybe stick those SR009 drivers into nice warm wooden cups, but who'd be Krazee enough to do something like that 

 

Maybe you could try out the Realiser A8 if you can as depending on the setup it can make the SR009 full-bodied while keeping its qualities. But since it is still an EQ for some people it just does not work as well as others, but it is definitely the best with the Stax headphones. Expensive and somewhat quirky to set up and use, but it can really do great things.

[Jon L]

Maybe you could try out the Realiser A8 if you can as depending on the setup it can make the SR009 full-bodied while keeping its qualities. But since it is still an EQ for some people it just does not work as well as others, but it is definitely the best with the Stax headphones. Expensive and somewhat quirky to set up and use, but it can really do great things.

 

My brain just exploded reading about the Realiser.  It seems to me the $3000 price (without the 'phones) would be worth it for me only if the premium room profiles were readily available for much lower prices or even for free.  It also seems like the reviewers who love the A8 mostly are guys who hate headphone listening to begin with, so making the headphones sound like speakers are amazing to them.  I on the other hand love headphone listening and already have a speaker system that satisfies that itch; I wouldn't want to turn my Stax experience to speaker experience.  What also makes the Realiser a non-starter for me is that its only digital output is toslink, whereas my DAC's sound best via USB or Firewire, even aes/ebu.  Realizer's only digital input is via HDMI as well.  Arrgg.  

 

Lastly, I'd rather save that $3000 towards a real good 'stat amp really.  But thanks for the interesting option, which I do hope to experience some day.

[padam]

My brain just exploded reading about the Realiser.  It seems to me the $3000 price (without the 'phones) would be worth it for me only if the premium room profiles were readily available for much lower prices or even for free.  It also seems like the reviewers who love the A8 mostly are guys who hate headphone listening to begin with, so making the headphones sound like speakers are amazing to them.  I on the other hand love headphone listening and already have a speaker system that satisfies that itch; I wouldn't want to turn my Stax experience to speaker experience.  What also makes the Realiser a non-starter for me is that its only digital output is toslink, whereas my DAC's sound best via USB or Firewire, even aes/ebu.  Realizer's only digital input is via HDMI as well.  Arrgg.  

 

Lastly, I'd rather save that $3000 towards a real good 'stat amp really.  But thanks for the interesting option, which I do hope to experience some day.

 

I agree the implementation is somewhat weird at the moment (probably due to licensing issues) but who knows what comes up next from their stable. The basic concept definitely works. I would say it is not really a speaker experience more like something in between, not too easy to describe.

 

It really depends on what you would like to improve upon. 

 

Anyway, amp-wise I can also suggest the modified SRM727. It runs fairly cool, takes up little space and works very well both with SR007Mk1 and SR009.

Of course I am sure it is no BHSE or KGSSHV but it is still pretty good and most importantly it is readily available (I guess HeadAmp can do the mod if requested as it is not nearly as fiddly as the SRM007t).

 

Rumor has it that Stax will release a new flagship amp to go with their flagship phone but so far nothing more has emerged.

Edited October 6, 2013 by padam

[grawk]

I've never noticed Justin offering modification services for other people's amps.

[Augsburger]

I just had this funky vision of Kevin/Birgir-designed innards with Electron Luv Steampunk "chassis."  And I drooled a little bit.....

X2!  Now that is something I would take out a second mortgage to buy.   Electron LUV amps are like Frank Cooter for speaker systems.

 

 

 

Well looks and build wise, I am not qualified to comment on design and tube implementation.

Edited October 7, 2013 by Augsburger

[padam]

I've never noticed Justin offering modification services for other people's amps.

If someone buys one directly from him it is possible (but of course no warranty). It is easier to do on the 727.

Edited October 7, 2013 by padam

[justin]

ive done the mods on both 007t and 727 that i didnt sell. its not something i advertise though. the price could be lower if i could get a dozen people to send their amps in instead of 1 or 2 per year

[spritzer]

Both amps are excellent when modified.  Pretty much transformed over the stock versions... 

[HeadphoneAddict]

 

Stax SR009 1 by drjlo1, on Flickr

 

My very own SR009 just arrived, as beautiful as ever.  

 

Although I already knew it, switching between SR007 MkI and SR009 in real time, I am severely struck by the fact there is NO way one system could be optimized for both 'stats.  If using the same amp, at least some tube and cable swapping must follow in order to enjoy both.  Now I wish for 'stats that combine the strengths of SR007 and SR009...maybe stick those SR009 drivers into nice warm wooden cups, but who'd be Krazee enough to do something like that 

 

 

Seriously?  Why assume wooden cups will be warmer sounding, or better?

 

And, I have a KGBH built by luvdunhill that is optimal for SR-007, SR-009, and HE-60 - no mods needed, no tube swaps or cable tweaking needed to make it sound good with any of them.  Granted, I can't say the same for the KGSS that he built, which my HE-60 don't like as much as the Stax do.

[Jon L]

Seriously?  Why assume wooden cups will be warmer sounding, or better?

 

And, I have a KGBH built by luvdunhill that is optimal for SR-007, SR-009, and HE-60 - no mods needed, no tube swaps or cable tweaking needed to make it sound good with any of them.  Granted, I can't say the same for the KGSS that he built, which my HE-60 don't like as much as the Stax do.

Well, woodies should introduce some warmish distortions/resonances to mask over SR009's prostate-exam-without-lube sensibility, at least I would presume. Even with KGBH, I still don't see how both SR007 and 009 could sound "optimal" at same time without any change in something. I am playing with SuperEQ software, and < 1dB shaving in the presence region and 1-2 dB boost in mid to low bass for SR009 is letting me enjoy both SR007 and SR009 with same setup, so that's a promising. Does a brand new SR009 need to be "broken in" a while before sound settles?

Edited October 12, 2013 by Jon L

[spritzer]

Nope, it always sounds like this.  That's also the reason why I don't own one...   

[harmonicorde]

I agree the implementation is somewhat weird at the moment (probably due to licensing issues) but who knows what comes up next from their stable. The basic concept definitely works. I would say it is not really a speaker experience more like something in between, not too easy to describe.

 

It really depends on what you would like to improve upon. 

 

Anyway, amp-wise I can also suggest the modified SRM727. It runs fairly cool, takes up little space and works very well both with SR007Mk1 and SR009.

Of course I am sure it is no BHSE or KGSSHV but it is still pretty good and most importantly it is readily available (I guess HeadAmp can do the mod if requested as it is not nearly as fiddly as the SRM007t).

 

Rumor has it that Stax will release a new flagship amp to go with their flagship phone but so far nothing more has emerged.

Interesting to hear about the new flagship from Stax. After reading hours of posts I recently bought the SR-009 with the SRM-323s. At the same time I was dreaming of the BHSE. But now I will wait

Listening to classical music and some jazz (on a low volume max 4) I am already very happy with the 323s !

[purk]

Interesting to hear about the new flagship from Stax. After reading hours of posts I recently bought the SR-009 with the SRM-323s. At the same time I was dreaming of the BHSE. But now I will wait

Listening to classical music and some jazz (on a low volume max 4) I am already very happy with the 323s !

 

It can get way better with the SR009.  Hope you can get your hand on the BHSE one day.