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Rogue Audio Sphinx V3 Review (Tube Amplifier)

SIY

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Nowadays tube amp has a LED below the tube, which is much brighter than the tube itself.
Wait! Solid state amp has LED as well.
In smart tube designs, the LED is functional, providing reference voltages and/or biasing.
 

fmplayer

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Let's recall it's just a matter of (objective) measurements vs (subjective) feelings.
Let me exemplify it another way:
Some years ago, I had some knee trouble. MRI showed anatomic joint disorders and the radiologist said I'd never be able to play tennis any more based on the images (read measurements). Before prescribing some physio and medication, the sports physician reminded me that radiologists only cure images, not people nor symptoms. After the physiotherapy was finished I started playing serious tennis again since then without (subjective) trouble.
Conclusion is that feelings may win against facts.
Same for audio stuff. People don't listen to distortion/noise but to sound/music. Measurements are crappy but they like it ? so be it. I'm happy for them. Same for stellar measuring stuff which some may dislike.
If some stuff pleases you whatever reason, go for it, and if not don't. Just admit that what pleases you may not please someone else
 

gsp1971

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Let's recall it's just a matter of (objective) measurements vs (subjective) feelings.
Let me exemplify it another way:
Some years ago, I had some knee trouble. MRI showed anatomic joint disorders and the radiologist said I'd never be able to play tennis any more based on the images (read measurements). Before prescribing some physio and medication, the sports physician reminded me that radiologists only cure images, not people nor symptoms. After the physiotherapy was finished I started playing serious tennis again since then without (subjective) trouble.
Conclusion is that feelings may win against facts.
Same for audio stuff. People don't listen to distortion/noise but to sound/music. Measurements are crappy but they like it ? so be it. I'm happy for them. Same for stellar measuring stuff which some may dislike.
If some stuff pleases you whatever reason, go for it, and if not don't. Just admit that what pleases you may not please someone else

Regarding your knee experience, could it be that the MRI (measurement) was not problematic but that your radiologist got it wrong (interpretation)?
Measurements do help, provided someone reads / interprets them the right way.

Regarding what people like and dislike, you are making a fair point.
But consider this extreme example: Assume that someone somewhere manages to build the perfect speaker. Completely flat response across the audio band, no resonances, no distortion, nothing. Simply perfect, OK?
The fact that some people will not like it, does it make it less perfect?
My point being that I do understand that there will always be 'stellar measuring stuff which some may dislike' and vice versa, but in there there is an element of 'people have learnt to like the wrong stuff and it is hard to undo that'.
People are resistant to change. That plays its part as well.
 
Last edited:

Xulonn

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You guys are dancing around with non sequiturs. What people "prefer" has never been a problem for reality-based audio objectivists, but claiming to hear what is proven to be inaudible is objectionable, as are claims that distorted or colored sound is more transparent or accurate than measureable flat frequency response.
 

Xulonn

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Perhaps you meant 'less transparent'?

Pure subjectivist audiophiles typically do not "claim" that their fairy-dust enhanced systems are "less" transparent.
 

Xulonn

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I misread it first time around. Thx.

I though that was possible due to ASR's global membership and multiple primary languages.

Upside-down Emoji.jpg
 

John Atkinson

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The distortion measurements he gets are perfectly in line with what Amir found . . .

My measurements of the Sphinx V3 clearly indicate that the second harmonic is the highest in level, somewhat different from what Amir found.

For comparison, here's a properly-designed tube preamp (since we want to look at tubes used for line-stage only), the Audio Research Reference 6E:
1020ARC6SEfig5.jpg


And here's a badly-designed tube preamp, the PrimaLuna EVO 400 :
619PLE400fig7.jpg

If you are going to use graphs from Stereophile in posts, I would appreciate you linking to the original reviews. My measurements of the Audio Research preamplifier can be found at https://www.stereophile.com/content/audio-research-reference-6se-line-preamplifier-measurements , the PrimaLuna preamplifier at https://www.stereophile.com/content/primaluna-evo-400-preamplifier-measurements

Thanks.

John Atkinson
Technical Editor, Stereophile[/QUOTE]
 

egellings

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I despise those LEDs below 12AX7's and the like, especially when the LEDs are any color other than orange! Let the tubes glow for themselves.
 

Peternz

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One explanation is people like it because of the distortion, not in spite of it. I'm not claiming this, but logically it fits.

OTOH, people letting sight of the marketing touting tubes and all the claims like it for what they think they are hearing rather than what they are hearing. That logically fits as well.

We here on ASR of course know what is needed to pick between the two hypothesis above.

Well, the truth is that people hear what they think they are hearing. The brain processes the information from the hearing apparatus. What people hear and what measuring equipment measures are two different things.

People like what they like and if they like distortion, they like distortion. It is what it is and it is the reason people buy this kind of product. It is their money, their ears and their brain and they are free to do as they choose.
 

levimax

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Well, the truth is that people hear what they think they are hearing. The brain processes the information from the hearing apparatus. What people hear and what measuring equipment measures are two different things.

People like what they like and if they like distortion, they like distortion. It is what it is and it is the reason people buy this kind of product. It is their money, their ears and their brain and they are free to do as they choose.

People are free to do as they chose and one choice is to become educated about the audio products they buy and study the science behind them rather than relying on subjective reviews or marketing or showroom demonstrations. ASR provides a great wealth of objective information and a range of opinions all in one place that was previously difficult or impossible for the consumer to get. What people do with this opportunity to learn and information is up to them of course.
 
OP
amirm

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If you are going to use graphs from Stereophile in posts, I would appreciate you linking to the original reviews. My measurements of the Audio Research preamplifier can be found at https://www.stereophile.com/content/audio-research-reference-6se-line-preamplifier-measurements , the PrimaLuna preamplifier at https://www.stereophile.com/content/primaluna-evo-400-preamplifier-measurements
Notice to members to please do this. Providing free access to measurements is a gift and we need to return the favor by linking to the review.
 

fmplayer

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Regarding your knee experience, could it be that the MRI (measurement) was not problematic but that your radiologist got it wrong (interpretation)?
Measurements do help, provided someone reads / interprets them the right way.
Nope. Radiologist was definitely right. Similarly, some people (rarely but it happens) suffer (small) acute myocardial infarction based on ECG without traditional big symptoms.
 

charleski

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My measurements of the Sphinx V3 clearly indicate that the second harmonic is the highest in level, somewhat different from what Amir found.



If you are going to use graphs from Stereophile in posts, I would appreciate you linking to the original reviews. My measurements of the Audio Research preamplifier can be found at https://www.stereophile.com/content/audio-research-reference-6se-line-preamplifier-measurements , the PrimaLuna preamplifier at https://www.stereophile.com/content/primaluna-evo-400-preamplifier-measurements

Thanks.

John Atkinson
Technical Editor, Stereophile
That’s true, I apologise for leaving out the proper links. Unfortunately the forum has a time-limit for editing posts so I can’t correct this in mine, but thank you for providing them for us.

As far as the Sphinx distortion graphs go, Amir does his snapshot at 5W, whereas yours was done at 60W and show a far higher level for the distortion components. So they’re not directly comparable, but give an indication of the likely extrapolation, which is what I tried to convey by ‘in line with’.

Since the distortion here will be almost entirely the result of the tube buffer, it seems to have been biased fairly hot such that it breaks further from linear at higher signal level. The measurements I’ve got from a (very different) tube amp suggest that the relative level of distortion components from tubes can vary quite dynamically as the output level changes, so any comparison of 2nd vs 3rd order etc would need to be done at the same level.
 

CrankyRat

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Let's recall it's just a matter of (objective) measurements vs (subjective) feelings.
Let me exemplify it another way:
Some years ago, I had some knee trouble. MRI showed anatomic joint disorders and the radiologist said I'd never be able to play tennis any more based on the images (read measurements). Before prescribing some physio and medication, the sports physician reminded me that radiologists only cure images, not people nor symptoms. After the physiotherapy was finished I started playing serious tennis again since then without (subjective) trouble.
Conclusion is that feelings may win against facts.
Same for audio stuff. People don't listen to distortion/noise but to sound/music. Measurements are crappy but they like it ? so be it. I'm happy for them. Same for stellar measuring stuff which some may dislike.
If some stuff pleases you whatever reason, go for it, and if not don't. Just admit that what pleases you may not please someone else

"MRI showed anatomic joint disorders and the radiologist said I'd never be able to play tennis any more based on the images (read measurements)."

Unfortunately your radiologist can only base there assessment on experience, a case of informed subjectivity. Only numbers are measurements, not images. And even numbers, unless backed up by rigorous peered reviewed science, get only faulty interpretations.
 
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