[purk]

Hi guys,

I joined the SR-009S club very late, after many years of joy with my Stax Lambda Professional, but yes it's huge step up and I'm very happy with this decision.

Congrats!

 

[urs]

h1f1add1cted​

Sorry about my ignorance:

Which amp is this on your photo ?

Thanks & Regards

Urs

 

[h1f1add1cted]

@urs

It's no Stax amp, it's the iFi Audio Pro iESL energizer, here my full setup: RME ADI-2 Pro FS R Black Edition > XLR > Audiophonics MPA-S250NC power amplifier (2x250 wpc) > speaker cable > iFi Audio Pro iESL



I used before a Stax SRD-7 MK2 energizer with my Stax Lambda Professional and it was great, but the iFi Audio Pro iESL energizer is just a whole new level, much cleaner output, greater staging/imaging, but less step-up ratio than the Original Stax energizer, but with a beefy power amplifer no problem at all.

 

[urs]

h1f1add1cted,

iFi Audio Pro iESL energizer ? interesting ?

Thanks &
Regards from Switzerland

Urs

 

[mammal]

iFi Audio Pro iESL energizer ? interesting ?

I believe amps for electrostats are commonly referred to as energizers.

 

[h1f1add1cted]

h1f1add1cted,

iFi Audio Pro iESL energizer ? interesting ?

Thanks &
Regards from Switzerland

Urs

Yes absolutly I love it, for me the cleanest solid state Stax experience compard to typical Stax amplifier like a STAX SRM-727 II. Also I can drive my regular headphones as well with it (like a Audio-Valve Solaris). And addtional fun note - I could drive a Sennheiser HE-60 or Sennheiser Orpheus HE-90 too (if I had one of this rare gems) because you can change the bias voltage to 540V or 500V (or other options) without any problem.

I believe amps for electrostats are commonly referred to as energizers.

No, those 2 different kind of devices. A Stax amplifer or "driver unit" is a real amp. A Stax energizer is no amp, there is no volume control or amp section, it's a voltage transformer and it requires a power amp.

 

[helljudgement]

No, those 2 different kind of devices. A Stax amplifer or "driver unit" is a real amp. A Stax energizer is no amp, there is no volume control or amp section, it's a voltage transformer and it requires a power amp.

Do you have any pictures on how it's connected power amp? I'm considering building a e-stats setup but is reluctant to get a separate amp just to run it. I'm using a studio b which has a pair of speakon outputs for driving efficient speakers so if this works I could use this in conjunction with the iESL to run stax off my existing SET amps.

 

[kzs70]

Yes absolutly I love it, for me the cleanest solid state Stax experience compard to typical Stax amplifier like a STAX SRM-727 II.

I have a STAX 727II as well, with the feedback modification and it is driving my SR-009.
I am not satisfied with the 727 and considering a KGSSHV Carbon amp upgrade, but this ifi iESL caught my attention.
Have you ever compared it with an other amp other than the 727?

I have a Lumin power amp driving my main speakers and also wondering about the efeffect of the ifi iESL on them if it's inserted in that system...?

 

[h1f1add1cted]

Do you have any pictures on how it's connected power amp? I'm considering building a e-stats setup but is reluctant to get a separate amp just to run it. I'm using a studio b which has a pair of speakon outputs for driving efficient speakers so if this works I could use this in conjunction with the iESL to run stax off my existing SET amps.

The Pro iESL has regular speaker connections. You only need a speakon to banana plug cable to connect it. It has loudspeaker input and output, because if the Pro iESL is powered off, the signal will be pass-through to your passive speakers (if you have any). That's why I connected not only the input, because I use with my power amp my ELAC speakers.

iFi Audio recommends 25W/4Ohm to 100W/8Ohm power input to drive the Pro iESL. My power amp has 150W/8Ohm so a way more than recommend, but this is not an issue, just careful use of volume to not blow your head off.

I have a STAX 727II as well, with the feedback modification and it is driving my SR-009.
I am not satisfied with the 727 and considering a KGSSHV Carbon amp upgrade, but this ifi iESL caught my attention.
Have you ever compared it with an other amp other than the 727?

I have a Lumin power amp driving my main speakers and also wondering about the efeffect of the ifi iESL on them if it's inserted in that system...?

No I have not compared to any aftermarket Stax amp, only with original Stax amps.

It's always a choice of personal preferences, some love big tube amps and would not use anything else ever. But I'm a solid state guy, I prefer clean transparent power, I don't want any "coloration" or change in sound, just massive power with zero disortion.

If you have a local dealer, ask for a loaner Pro iESL unit and try by yourself at home with your power amp, trust your ears and the decision will be clear.

 

[kzs70]

Thanks for your answer but unfortunately there is no local dealer here who could loan one to try it.
In your setup the speakers are connected to it too. Does it pass through the signal when it is switched off, like a passive switch?
And do you hear any difference in your speaker system when this ifi iesl is in the chain vs. speakers are directly connected to the power amp?

 

[helljudgement]

The Pro iESL has regular speaker connections. You only need a speakon to banana plug cable to connect it. It has loudspeaker input and output, because if the Pro iESL is powered off, the signal will be pass-through to your passive speakers (if you have any). That's why I connected not only the input, because I use with my power amp my ELAC speakers.

iFi Audio recommends 25W/4Ohm to 100W/8Ohm power input to drive the Pro iESL. My power amp has 150W/8Ohm so a way more than recommend, but this is not an issue, just careful use of volume to not blow your head off.

Thanks for the pic. Glad to know it has both input and output connectors which can be used as a pass through for speakers. My amp is way below the recommended wattage by IFI, providing only 4w for said rating so will have to try it out to see if it is sufficient.

 

[h1f1add1cted]

Thanks for your answer but unfortunately there is no local dealer here who could loan one to try it.
In your setup the speakers are connected to it too. Does it pass through the signal when it is switched off, like a passive switch?
And do you hear any difference in your speaker system when this ifi iesl is in the chain vs. speakers are directly connected to the power amp?

A mentioned in my post before the signal is pass-through when the Pro iESL is powered off. It's 100% passive, zero change of the signal if using it over Pro iESL. If the loudspeakers are directly attached to the power amp no difference.

Thanks for the pic. Glad to know it has both input and output connectors which can be used as a pass through for speakers. My amp is way below the recommended wattage by IFI, providing only 4w for said rating so will have to try it out to see if it is sufficient.

You can set the impedance setting of the Pro iESL to lower settings like 16 or 24 Ohm, with this setting you could get enough SPL depending on the Stax headphone you are using, but I suspect it will be enough to drive a 007 MKII well for example and the 009 also scales pretty well with a good amp. It's better to set the impedance setting of the Pro iESL to 64 or 96 Ohm to get more filtering and cleaner sound, but this requires a more powerful source to drive it well.

But optional there is also a other method to drive the Pro iESL. If you have a powerful headphone amp with 4-Pin XLR output you can directly attach your headphone amp to the Pro iESL 4-Pin XLR input on the back. I tried this already and it's working fine too, but I prefer my power amp.

 

[kzs70]

A mentioned in my post before the signal is pass-through when the Pro iESL is powered off. It's 100% passive, zero change of the signal if using it over Pro iESL. If the loudspeakers are directly attached to the power amp no difference.

Thanks for the clarification!

 

[helljudgement]

You can set the impedance setting of the Pro iESL to lower settings like 16 or 24 Ohm, with this setting you could get enough SPL depending on the Stax headphone you are using, but I suspect it will be enough to drive a 007 MKII well for example and the 009 also scales pretty well with a good amp. It's better to set the impedance setting of the Pro iESL to 64 or 96 Ohm to get more filtering and cleaner sound, but this requires a more powerful source to drive it well.

Thanks for the advice. Gonna be very difficult to try it out before making a purchasing decision but it is good to know that such an option is available for folks like me who would much rather make use of existing setup rather than to build a whole new setup just for e-stats. It is gonna be very interesting to hear how it pairs with SET amps for speakers. I do think the traits of 300b tubes would synergize well with stax especially with the 009.

 

[Sajid Amit]

Talk to Paul at HiFi Lounge. I got my 009S from him. He should have no issues with you borrowing a demo unit of both headphones as long as you do the honourable thing and buy at least one in the end.

This has been beaten to death I am sure - but can I get some quick impressions comparing the 009 vs the 009S?

Too subtle to make a big difference?