Amp for very specific listening needs...

[TheSloth]

Hello everyone, it's been years... (for anyone that remembers me anyway)

I am researching what amp best suits my somewhat bespoke needs, and thought there might be some useful opinions here, especially since I've been rather out of it for ages.

To cut a long story short, about one year ago I suffered an accident that damaged my ears, the result being that I have severely reduced dynamic range in my hearing. Though my sensitivity is normal and frequency response is good (i.e. little to no hearing loss), my pain and distortion threshold has been lowered to around 80dB. This means that for real music listening (classical in my case), I can manage with a level that sets absolute peaks at around 85dB.

In order to maximise what I can get out of my remaining dynamic range, I find myself using IEM's (Ety 4XR currently) to cut background noise to a minimum. So I'm currently looking for an amp that would have vanishingly low distortion and noise into this kind of setup. Maximising transparency (of the 'straight wire with gain' kind, not 'extra detail' or anything described with a fancy sounding adjective), through minimum distortion, noise etc. are top priorities, whereas output power is relatively irrelevant for such low listening levels even with much more demanding headphones. In fact, with those kinds of levels I don't even need a gain stage per se, as a gain of 1x is usually too much to get into most volume pots' optimal range. In a way, I guess I'm looking for a maximally transparent headphone buffer, if such a design exists out there on the market.

I don't care about the power scheme either - battery only, rechargeable, A/C only, it's all the same to me. I just want to get the absolute maximum from the music that what's left of my ears will allow...

Any ideas?

Edited January 3, 2018 by TheSloth

[dsavitsk]

I made a buffer for crappyjones123 that fit this description a couple of years ago. Send him a PM. He was selling it at one point.

[Dusty Chalk]

Sorry to hear about your injury, yes, I remember the classically trained pianist, of course I do, welcome back, even if briefly.

That is all -- hope the babying of your ears give them the chance to heal.

[purk]

Thanks for checking in and hope your hearing will heal sooner or later.  Do u have any budget in mind?

[mypasswordis]

https://www.quietcommunities.org/noise-level-hearing-loss-prevention/

 

http://hearinglosshelp.com/blog/what-are-safe-sound-levels/

[TheSloth]

Thanks for the comments so far...

My budget is whatever it takes . Ok, so not exactly - I refuse to spend just for the sake of it, but if there is a clearly demonstrable reason why I am getting more for my very specific use case after spending more, I'll consider it. I'm a bit of an objectivist at heart, so I'm not easy to convince on that one.

The thing I see a lot when looking at amplifier designs is a lot of consideration on how to handle voltage gain, which is pretty irrelevant to me. The other thing I see often is crosstalk numbers and channel balance numbers that I'm not happy with. I expect channel balance to be pretty much 0dB at any volume setting, and crosstalk to be <-80dB across the entire audio band. I know that the audibility of crosstalk that is significantly worse than -80dB is debatable, but my brain needs to know that it's taken care of either way. 

And just in case I wasn't clear, this is an injury related to a somewhat tragic accident, not exposure to high volumes. I spent my life caring for my ears in every way possible, watching people around me ruining their hearing. But that's life, things can happen in the blink of an eye that render decades of effort moot.

 

Edited January 4, 2018 by TheSloth

[purk]

I would get Doug to build you an amp for what u need.  He can cater to what u need and his amps all sound amazing.

[recstar24]

The pico slim I believe is a very high quality buffer with excellent channel balance made specifically for iems, correct?

[crappyjones123]

I had indeed gone through some financially troubling times and was trying to raise money for something else when the amp Doug had built for me was on the chopping block but I am glad I was not able to sell it. My requirements were very similar to yours and I was elated with what Doug sent me. I perhaps had the opposite issue - my hearing is/was too sensitive. I heard the noise/hiss from the equipment in the background even at low volumes. I tried the pico slim as well but still had that pervasive hiss in the background. I think for anyone who doesn't have the absurd ears I do, it would make for a great amp. 

My personal experience with Doug leads me to make the same suggestion purk made - convince Doug to make you something. I gave him my requirements and he came up with the gorgeous looking piece of kit and works better than it looks. 

[Dusty Chalk]

If I recall correctly, the Accuphase sounded really good at extremely low volumes.

[TheSloth]

23 hours ago, crappyjones123 said:

I had indeed gone through some financially troubling times and was trying to raise money for something else when the amp Doug had built for me was on the chopping block but I am glad I was not able to sell it. My requirements were very similar to yours and I was elated with what Doug sent me. I perhaps had the opposite issue - my hearing is/was too sensitive. I heard the noise/hiss from the equipment in the background even at low volumes. I tried the pico slim as well but still had that pervasive hiss in the background. I think for anyone who doesn't have the absurd ears I do, it would make for a great amp. 

My personal experience with Doug leads me to make the same suggestion purk made - convince Doug to make you something. I gave him my requirements and he came up with the gorgeous looking piece of kit and works better than it looks. 

Thanks for that - interesting observations on the pico, I would have expected that to be very quiet. I'm not sure how absurd my absolute sensitivity is, but the fact is that my own dynamic range is so limited that even losing just a few dB to hiss is significant to me.

Do you have any more details about your buffer?

[dsavitsk]

2 hours ago, TheSloth said:

Do you have any more details about your buffer?

I guess I can answer this It is a diamond buffer, but it uses servo controlled current sources to maintain stability and improve performance. It also has JFET input and Sziklai output devices for low distortion and low noise. The PS uses Jung regs. And we kept the raw PS external to eliminate any chance of noise being picked up (I think CJ's uses an external switcher, but a transformer works, too).

Edited January 6, 2018 by dsavitsk

[crappyjones123]

Yup. Exactly what I was going to say. 

 

[TheSloth]

On 06/01/2018 at 2:40 AM, dsavitsk said:

I guess I can answer this It is a diamond buffer, but it uses servo controlled current sources to maintain stability and improve performance. It also has JFET input and Sziklai output devices for low distortion and low noise. The PS uses Jung regs. And we kept the raw PS external to eliminate any chance of noise being picked up (I think CJ's uses an external switcher, but a transformer works, too).

Actually that does sound really great. What volume control setup did you go with? And as I understand it no gain stage at all?

In other directions, anyone have any experience with the Benchmark DAC/amps?

[dsavitsk]

Alps blue. No gain.

[purk]

On 1/8/2018 at 5:40 PM, TheSloth said:

Actually that does sound really great. What volume control setup did you go with? And as I understand it no gain stage at all?

In other directions, anyone have any experience with the Benchmark DAC/amps?

My experience was with the DAC-1 USB and their headamp was not impressive.  Really a mid-end at the most.

Edited January 9, 2018 by purk