[playmusic]

Thank you for your feedback on my bass reproduction question.

Another question I have is about the necessity of headroom for amplifiers for Stax headphones.
Current Stax headphones are specified with a sensitivity of 101 dBSPL @ 100 Vrms and 1 kHz.
There are two cases where I listen at high SPL levels up to105 dBSPL:

• Classical music where the rms is up to 20 dB lower than the peak of the soundfile.
• Bass-focused music. (This music is percieved as quieter than music of the same rms but with a significant part in 1 kHz - 8 kHz. This different perception is described by the Fletcher-Munson curves)

105 dbSPL requires ca. 160 V with a Stax headphone.

The SRM-D10 has a Vrms max of 200 V, so there is a headroom of 2 dB.
The other Stax amplifiers have a maximum of 300 - 470 Vrms, so they have a headroom of 5 - 10 dB.

Some people claim that a large headroom (significantly higher than 10 dB) is required to deal adequately with transients.

How is the situation with Stax headphones and amplifiers in your experience?

 

[tabness]

The new Advanced Lambda series has a midbass hump likely due to being ported (this has been shown in various measurements and I have 009S and L500 MKII and I hear it this way as well). I do think the 009S has a slightly better and more natural timbre than the L500 (L500 is brighter) though, but the 009S seems to be just a bit off in timbre compared to some of my other headphones (R10 for sure, CD3000 as well although the CD3000 is a bit artificially exciting itself, the Stax Omega in general).

The 009S is still my favorite Stax headphone (Omega may be have natural timbre but it's less exciting/sparkly and L500 the main difference is the soundstage/separation more so than the slightly brighter tonality).

Once you get to the "full size" Stax driver units (353X/006tS and up) you should have enough voltage swing unless you want to (dangerously) listen near the max db SPL of the headphone itself. The thing that's bought up is slew rate limiting for the Stax driver units at those voltages at higher frequencies, but again, the fact that the power bandwidth of most audio signals would be 3 kHz to 5 kHz it's very unlikely that there would be any issues with this happening in almost every recording that exists. After that's it's a matter of the linerarity of the amp and all that (353X should be very linear, but I also have T1S and while it might be colored a bit (more full bass), for me it really isn't any big difference as compared to the transducers themselves).

 

[T3RIAD]

f

How is the situation with Stax headphones and amplifiers in your experience?

This is a rather controversial topic. Some people say that you shouldn't bother with the SR-009 if you can't get a $5,000 third-party amp to go with it. Then there are some who say that even a Stax D10 driving an SR-007 is adequate unless you like to listen really loud.

From a technical standpoint, the Stax amps have plenty of voltage to drive any of their headphones as loud as they can possibly go. The main disadvantage I've heard is that Stax amps are current limited. For e-stat headphones, the higher frequencies require more current to drive than the lower frequencies. The Stax amps only have enough current to drive frequencies up to 10 kHz at maximum volume.

We can't hear distortion at that frequency, but if you listen really loudly, the high frequencies might be attenuated with a Stax amp. Also, many of the third-party amps have regulated power supplies, though it's unclear to me how that would affect the sound.

I have a Stax SRM-353x powering the SR-009S. It sounds great to me. I haven't heard a high-end amp, so it's possible they could sound even better. I'm personally skeptical it would make much of a difference, if any.

 

[walakalulu]

Stax amps tend to soften the low frequencies too.

 

[playmusic]

The Stax amps only have enough current to drive frequencies up to 10 kHz at maximum volume.
We can't hear distortion at that frequency, but if you listen really loudly, the high frequencies might be attenuated with a Stax amp.

I see your point that harmonics of 10 kHz are not audible.

It seems that amps for Stax headphone are working "near to the limit" at high volumes.
This might be a reason that tubes and transistors actually behave differently at those constellations even if they measure the same in the "linear" i.e. specified range.
There is an intersting article "Tubes vs transistors is there an audible difference" by Russell O. Hamm from 1973 available for free at several places on the internet.
Basically, the article shows that tubes are more pleasing than transistors to the ear during recording and playback when they are operated outside the specified range.

I have a Stax SRM-353x powering the SR-009S. It sounds great to me. I haven't heard a high-end amp, so it's possible they could sound even better. I'm personally skeptical it would make much of a difference, if any.

Good advice, this approach sounds reasonable to me.
Thank you!

 

[BowWazoo]

I owned the Focal Stellia and the Final Audio D8000,
but the Stax sr-l507 destroys both of them plainly.
I am absolutely thrilled...

Here is my EQ preset

 

[Amish]

I have a Stax SRM-353x powering the SR-009S. It sounds great to me. I haven't heard a high-end amp, so it's possible they could sound even better. I'm personally skeptical it would make much of a difference, if any.

I own a Mjolnir Audio Octave III. The Octave being inspired by the SRM-353X. Basically a simplified KGSSHV. That said he (the builder) claims it will easily drive any of the Lambda up to SR-009. I believe the 353X would do the same and from what you stated, you concur.
On topic I can say that I have only owned one STAX amp, the STAX SRM-T1 and though it sounded lovely, it just did not have the ability to drive my L700mkII to full authority. The Octave does and then some. I can crank the Octave as loud as I can stand it, to the point of pain and it is still clean. I'd love to try one of those $5k amps but honestly i am so happy with the Octave and L700 that I just do not see the point of such a large investment.

 

[daytrader]

So I came up upon the Stax 353x BLk 80th Anniversary energizer on the elusiveDisc website. Is this unit still available? I thought only a limited supply of 300 were offered back in 2018 and they’ve been long gone sold out ever since? I checked around all the other Stax retailers here in the US, Apos, Stax.usa(Woo) and even HeadAmp, none of them have it. Was always curious about this edition, were they actually any different than the standard 353x or just marketing hype? The L300LE was said to have come very close to the L700 after reviews came out as compared to the standard L300 so one would think the 353x BLK LE would have follow suite?

 

[RKarim]

(deleted)

 

[BowWazoo]

Does anyone know a mobile amp,
with 580V Bias, as an alternative to the Stax D10?

 

[mnemonix]

So I came up upon the Stax 353x BLk 80th Anniversary energizer on the elusiveDisc website. Is this unit still available? I thought only a limited supply of 300 were offered back in 2018 and they’ve been long gone sold out ever since? I checked around all the other Stax retailers here in the US, Apos, Stax.usa(Woo) and even HeadAmp, none of them have it. Was always curious about this edition, were they actually any different than the standard 353x or just marketing hype? The L300LE was said to have come very close to the L700 after reviews came out as compared to the standard L300 so one would think the 353x BLK LE would have follow suite?

It's specification is identical to the SRM-353X and I've never read anything implying even a minor upgrade in components so I believe the only difference was the colour and a badge.

 

[Mach3]

So I came up upon the Stax 353x BLk 80th Anniversary energizer on the elusiveDisc website. Is this unit still available? I thought only a limited supply of 300 were offered back in 2018 and they’ve been long gone sold out ever since? I checked around all the other Stax retailers here in the US, Apos, Stax.usa(Woo) and even HeadAmp, none of them have it. Was always curious about this edition, were they actually any different than the standard 353x or just marketing hype? The L300LE was said to have come very close to the L700 after reviews came out as compared to the standard L300 so one would think the 353x BLK LE would have follow suite?

Besides the gold badge and black paint it the same unit as the 353x, confirm this already.

 

[kevin gilmore]

Does anyone know a mobile amp,
with 580V Bias, as an alternative to the Stax D10?

srm252 with a decent sized 12V lithium ion battery glued to the top or bottom.

 

[jsts]

We also tried his RME ADI-2 DAC with the various amps as well.

Thank you for the overview.

My two cents.

I sold my DAC RME ADI-2 and switched to Chord Hugo 2. The reason is simple: RME ADI-2 is very sharp, very detailed, very bright. I chose a slightly calmer Hugo 2 for comfortable listening on electrostats (SRM-600LTD + SR-007MKII).

Just sharing my experience

 

[jsts]

srm252 with a decent sized 12V lithium ion battery glued to the top or bottom.

lol