Rupert Neve RNHP Headphone Amp Review

[solderdude]

Let's put it this way. If you want to prove, to yourself basically, and after that to the tough ASR crowd, you should test with some controls.

1: remove bias (by not knowing what is playing)
2: level the playing field (requires measurements under load condition with a resolution better than 1% (0.1dB)
3: statistical rigor (enough 'blind' attempts to ensure you were not getting results better than you were guessing)

Omitting one of these or not doing them properly null and voids the results as 'evidence' to yourself and others.
These controls are far more important than most reviewers think they are and can 'reason' away.

Just for the fun of it adhere to these rules if only to test your own hearing abilities instead of hearing+looking+thinking+emotions+biases+opinions to form a 'not so well educated' conclusion.

 

[mokoaguswan]

Hi Solderdude,

I don’t need to prove anything to myself nor the ASR tough crowd.
I’m pretty happy not to go through the rigorous test you are suggesting.
I pretty much value my not so well educated opinion to my own.

 

[solderdude]

At ASR your opinion thus may not be considered as reality but rather your personal subjective finding based on incorrect 'testing'.
It is fine if you state:
"Honestly, I don't consider it acoustically transparent. It smoothens the high frequency in a good way (good for brighter headphones -grado/sony) but didn't work out well with Neumann NDH20 and LCD4 (that I use). I use headphones primarily to monitor. As for the claim of sounding 'richer/fuller', I hear the bump in the low mids more than the little labs monotor."
But you state this as being the reality.
It IS a reality to you of course and thus 'valid' but most ASR members know your findings can not be attributed to the amplifier.

However, I would be interested to know if I was fooling myself or not, so while you may not want to go through the trouble and educate yourself, some others did and got a little wiser because of it.

 

[mokoaguswan]

When one is looking at measurements of course they would be looking (using eyes) rather than listening but not be looking by hearing as one cannot see with the auditory system.... well.... some blind people may be sort of exempt.

If you look at measurements and can describe how it sounds you could either be quite knowledgeable, clueless or anything in between.

Honestly this statement perplex me. I can't really relate to this well.

I am trying to understand this more. Maybe I should stop hijacking this thread and post in other threads.

 

[mokoaguswan]

At ASR your opinion thus may not be considered as reality but rather your personal subjective finding based on incorrect 'testing'.
It is fine if you state:
"Honestly, I don't consider it acoustically transparent. It smoothens the high frequency in a good way (good for brighter headphones -grado/sony) but didn't work out well with Neumann NDH20 and LCD4 (that I use). I use headphones primarily to monitor. As for the claim of sounding 'richer/fuller', I hear the bump in the low mids more than the little labs monotor."
but then you state this as being a reality. It IS reality to you but most ASR members know these findings can not be attributed to the amplifier.

However, I would be interested to know if I was fooling myself or not so while you may not want to go through the trouble and educate yourself some others did.

I stated it as a personal subjective opinion didn't I?
I gave that what I heard in comparison to the little labs monotor.

I'm not sure how my experience with the unit is perceived as a measured and technical findings?

 

[solderdude]

Maybe I should stop hijacking this thread and post in other threads.

Write a PM to @Thomas savage (admin) and tell him which posts (the numbers in the right corner of the posts) you would like to see moved and ask him to create a new thread in: https://www.audiosciencereview.com/forum/index.php?forums/psychoacoustics-science-of-how-we-hear.20/ forum.
There you can have discussions about this type of things.

If anything the RNHP cannot 'smooth high frequencies' nor have a 'bump in the low mids' despite you perceiving this.

 

[SpeleoFool]

FWIW, the review amp was mine, and I've currently got it on my desk driven by the balanced out of an RME ADI-2 DAC that is also driving a Monoprice 887 via RCA. The RME drives both amps at the same time, enabling me to do direct comparisons of headphones playing from each. I also happen to own two Focal Elegias, which I used for a sighted direct A-B comparison between the two amps.

Short version: I could not hear any difference between the two amps. I played a variety of my personal reference tracks that I know well and went back and forth between the headphones listening for things like fine detail retrieval, decay, and any sense of tonal differences or other unique aspects of sonic presentation in either amp. I came up empty, leading me to conclude that any actual differences are either too subtle for me to perceive or fall within the spectrum of variable listening impressions that can be affected by things like mood, fatigue, etc.

FWIW, my background is in ASIC verification (which basically just means I am conditioned to do meticulous diagnostic analysis--a habit that I've carried over to exploring audio). I favor a scientific, skeptically-driven approach to identifying sonic differences between equipment. I try to be mindful of all of the variables in play when I listen, and I consider it crucial to check my work to see if my perceptions are repeatable. I do have some extremely resolving headphones like Focal Stellia and Utopia, and Stax L700, so I've got some experience with what to listen for to detect very fine differences as playback resolution approaches perfection.

In any case, my little experiment was not rigorously controlled enough to be considered scientific, even if I did go out of my way to eliminate or minimize as many variables as possible. I evaluated the RNHP against an amp that measures as objectively pristine, and found that both are essentially transparent. Despite my assurances that I didn't undertake this experiment naively, my conclusions shouldn't be taken as anything other than what they are--just one more subjective opinion.

The upside for me is that this dual-amp setup has been indispensable for comparing various headphones against one another. It's much easier to swap cans as music is playing than it is to rewind, re-listen and second-guess whether I'm hearing real differences or just paying attention differently.

 

[Hemi-Demon]

FWIW, the review amp was mine, and I've currently got it on my desk driven by the balanced out of an RME ADI-2 DAC that is also driving a Monoprice 887 via RCA. The RME drives both amps at the same time, enabling me to do direct comparisons of headphones playing from each. I also happen to own two Focal Elegias, which I used for a sighted direct A-B comparison between the two amps.

Short version: I could not hear any difference between the two amps. I played a variety of my personal reference tracks that I know well and went back and forth between the headphones listening for things like fine detail retrieval, decay, and any sense of tonal differences or other unique aspects of sonic presentation in either amp. I came up empty, leading me to conclude that any actual differences are either too subtle for me to perceive or fall within the spectrum of variable listening impressions that can be affected by things like mood, fatigue, etc.

FWIW, my background is in ASIC verification (which basically just means I am conditioned to do meticulous diagnostic analysis--a habit that I've carried over to exploring audio). I favor a scientific, skeptically-driven approach to identifying sonic differences between equipment. I try to be mindful of all of the variables in play when I listen, and I consider it crucial to check my work to see if my perceptions are repeatable. I do have some extremely resolving headphones like Focal Stellia and Utopia, and Stax L700, so I've got some experience with what to listen for to detect very fine differences as playback resolution approaches perfection.

In any case, my little experiment was not rigorously controlled enough to be considered scientific, even if I did go out of my way to eliminate or minimize as many variables as possible. I evaluated the RNHP against an amp that measures as objectively pristine, and found that both are essentially transparent. Despite my assurances that I didn't undertake this experiment naively, my conclusions shouldn't be taken as anything other than what they are--just one more subjective opinion.

The upside for me is that this dual-amp setup has been indispensable for comparing various headphones against one another. It's much easier to swap cans as music is playing than it is to rewind, re-listen and second-guess whether I'm hearing real differences or just paying attention differently.

How did you level match the two outputs back and forth without creating bias? Aren't the balanced outputs on the RME hotter than its RCA jacks?

 

[SpeleoFool]

How did you level match the two outputs back and forth without creating bias? Aren't the balanced outputs on the RME hotter than its RCA jacks?

I tuned levels by ear at the amp outputs until both headphones sounded the same. I don't have a reliable means to measure, so I had to take my best guess. Using two sets of Elegias helped immensely to make sure I had a close real-time level match as opposed to moving a single set of headphones back and forth and relying on listening memory as an aid.

I think balanced is always hotter than RCA when both outputs are present (at least that's always how I've seen it implemented). In any case, one could argue the entire XLR signal path is different from the RCA path, so that's another potential source of error / deviation. Same deal for unit variation in the headphones, etc., though some of that I could have tested for by swapping headphones to the opposite amps to see if perceptions changed.

I opted to give the RNHP the XLR path to give it the best opportunity to present some kind of subjective magic vs the THX amp. I also stuck to 1/4" outs of both amps (RNHP only has 1/4") to avoid differences related to crosstalk. I was actually hoping to hear some kind of repeatable difference so that I could explore that further, but not finding any suggests to me that there's likely not one. I should not be able to introduce multiple sources of error and get the same results.

 

[gearocdguy]

For what it is worth, I recently spent two weeks with RNHP and the THX789 (prior to reading this post) with four different headphones.

The headphones were my old T5P 1 Gen, Elegia, Aeon 2C, and Ether CX. The RNHP really struggled with the CXs which, if I am honest probably negatively impacted my impression of them unfairly. I didn't enjoy the Elegia on either amp. I thought the Aeon 2Cs had more energy on the RNHP. But, the biggest difference was with my old T5Ps. The RNHP brought them back from the dead.

I really wanted to like the THX789 and only ordered the RNHP because they are all over Amazon and dead easy to return. In the end I decided to keep the RNHP and return the THX789. I am not claiming I did a particularly scientific A/B, nor do I consider myself a skilled critical listener, but I did hear a noticeable improvement on the T5P and a slight improvement with the Aeon 2Cs with the RNHPs despite my priors.

Hopefully, this adds some value to the conversation.

 

[YSC]

For what it is worth, I recently spent two weeks with RNHP and the THX789 (prior to reading this post) with four different headphones.

The headphones were my old T5P 1 Gen, Elegia, Aeon 2C, and Ether CX. The RNHP really struggled with the CXs which, if I am honest probably negatively impacted my impression of them unfairly. I didn't enjoy the Elegia on either amp. I thought the Aeon 2Cs had more energy on the RNHP. But, the biggest difference was with my old T5Ps. The RNHP brought them back from the dead.

I really wanted to like the THX789 and only ordered the RNHP because they are all over Amazon and dead easy to return. In the end I decided to keep the RNHP and return the THX789. I am not claiming I did a particularly scientific A/B, nor do I consider myself a skilled critical listener, but I did hear a noticeable improvement on the T5P and a slight improvement with the Aeon 2Cs with the RNHPs despite my priors.

Hopefully, this adds some value to the conversation.

I personally thinks that might be due to personal preference, no conflict to the review here, in reality beside objective measurements the combination of the phones you used and other effects like brand preference will make the whole experience different. and long been the theory of the harmonic distortions are preferred by some people.

If any more measurements I would want to see is maybe anirm can figure out a headphone measurement curve as what Tyll have done, so maybe we can see how one dac/amp measures purely objectively as we always have, but then added in how/does the selected headphones like the Ether CX, or any other common headphones did/didn't change the freuency response or impulse response etc. which correlates to all our subjective experience?

 

[solderdude]

Tyll hasn't done many headphone measurements using different amplifiers.
Frequency response may differ depending on output resistance of the amp (measured by Amir already in most cases) or headphone impedance combined with output transformers or capacitance (when capacitor coupled). This can partly be deducted from FR plots using 300 and 32 Ohm loads.
Also a lack of output power in specific headphone impedances can play a role as to how a headphone sounds. This too is already measured by Amir and info on headphone efficiency (and sometimes even impedance plot) can be found on the web.

There are literally hundreds of different headphones and some of them are reacting substantially on higher output resistances, others may not react at all or just slightly. So while one could easily connect 3 or 4 different headphones and measure the electrical input to the actual headphone it won't say anything about other headphones.

When you don't want to be bothered simply look for an amplifier with a low output resistance (say < 1 Ohm) and with enough power (say above 200mW in headphone impedances you own or plan to own) and a wide enough frequency response (20Hz to 20kHz within 0.5dB as a minimum) and low enough distortion (below 0.01%) and low enough noise levels. The latter is depending on efficiency of the (to be) used headphones.

Then there is clipping behaviour which is rarely tested, at least with oscilloscope shots showing a clipped sinewave.

 

[armani006]

Someone asked what the Gain is for all three inputs. Here it is:

Hi Amir, I have a question a bit different from this theme, I wonder how to perform measurements for electrostatic amplifier, this can be very interesting for big Stax community. Seems like you didn't do this before? May be it is obligatory to add resistors on output of such amp. ?

 

[gearocdguy]

I personally thinks that might be due to personal preference, no conflict to the review here, in reality beside objective measurements the combination of the phones you used and other effects like brand preference will make the whole experience different. and long been the theory of the harmonic distortions are preferred by some people.

If any more measurements I would want to see is maybe anirm can figure out a headphone measurement curve as what Tyll have done, so maybe we can see how one dac/amp measures purely objectively as we always have, but then added in how/does the selected headphones like the Ether CX, or any other common headphones did/didn't change the freuency response or impulse response etc. which correlates to all our subjective experience?

As an update on my previous post, after reading the ASR review of the RNHP and making my previous comments, I convinced myself I was hearing distortion on the RNHP while listening to the A2C and returned it. I purchased a Jotunheim. Mostly because I wanted to run XLR cables across my home office to share my Qutest with my integrated AMP. But, also because I am too sheepish to go back and purchase another 789 from Drop after returning the first. The Jotunheim definitely feels like a downgrade, except when listening to grunge. I since found an RNHP and a Gilmore Lite Mk1 (who can say no to cheap class A) on eBay which I bought mostly to make myself more nuts. I am now fighting my demons on cables. I know I don't hear a difference between Amazon Basics and the rest. But, the aren't as pretty the red white and blue "patriot edition" Silver Serpents nor do they have the Audioquest Logo on the connectors. Bottom line, if anyone is looking for a greater fool to unload your unwanted equipment. Just tell me a tale and I am probably your guy.

 

[solderdude]

Hi Amir, I have a question a bit different from this theme, I wonder how to perform measurements for electrostatic amplifier, this can be very interesting for big Stax community. Seems like you didn't do this before? May be it is obligatory to add resistors on output of such amp. ?

Not Amir, but sadly enough it isn't as simple as just lowering the high output voltage using resistors as an actual load (the electrostatic driver) is only capacitive. Using resistors as voltage dividers isn't the same as the actual load.

 

[armani006]

Using resistors as voltage dividers isn't the same as the actual load

I understand this, as well as this is not a simple task. So, we have to think about this )) We send space ships into the Space.. we can find a way to measure electrostats... )

 

[solderdude]

You can measure electrostatic headphone amps. The point is there aren't many of those. It is a niche within a niche market. Why would Amir have to invest in this ?

 

[armani006]

The point is there aren't many of those. It is a niche within a niche market. Why would Amir have to invest in this ?

I see, may be Amir thinks the same..

 

[imrul]

Maybe, but part of his drive is to prove that the emperor has no clothes. Electrostatic amplifiers can certainly use the light Amir sheds on audio devices as any sort of review I've seen electrostatics has been purely subjective. Those reviews contain the same subjective lingo used in other audiophilic reviews with often a sprinkle of technical jargon thrown in to make the product appear esoteric, enigmatic, with the magical ability to take you music to the next level.

So yes, some objective measurements would be very helpful in this field.

 

[NTomokawa]

not particularly broken

-83.3 decibels. Not great, not terrible.

Oh well!