So tell me, according to your analysis which ones are loudest and by what dB levels are they different? I'm sure your DAW can spit out an average RMS loudness number. But please post as a hidden txt file upload so people have to click on it to see the answer. I don't want to influence the polll.
Could it be that an amp with very strong dynamics and transients have deep bass response and snappy transients may be perceived as louder when in fact settings for max SPL are the same?
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Each amp will have a natural filtering (low and high pass) which will affect the wave shape and change peak amplitudes slightly. This is why normalizing based on peak amplitudes does not give expected results. RMS levels must be used...
Or ideally, amps should have been adjusted for exactly the same gain prior to recording, but that would have been quite a bit of extra work.
I attempted extraction of differences between recorded files and original, but what I get are mostly MP3 encoding artifacts. No luck here...
Or ideally, amps should have been adjusted for exactly the same gain prior to recording, but that would have been quite a bit of extra work.
I attempted extraction of differences between recorded files and original, but what I get are mostly MP3 encoding artifacts. No luck here...
Of course, I wouldn't ask you to redo the whole thing!
FLAC will do nicely. There's no difference with WAV except the smaller size.
no that is strange - because A, F and G were my favorites
. anyhow, thank you very much for your work, xrk. i am looking forward to see what ampflifier belongs to what letter because i want to get a new amp .
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Just a reminder that there is a nice prize for the person who identifies the most (with at least 4 correct) sound clips with their respective amplifier. Here is the Pocket Class A Headamp prize.
http://www.diyaudio.com/forums/group-buys/302859-xrk971-pocket-class-headamp-gb.html
Underside:
Only top quality components are used.
Measured HD:
Measured frequency response and THD as function of frequency:
How does it sound? Well, despite its dimunitive proportions, there is no shortage of performance. Simply one of the best sounding headphone amplifiers I have heard.
http://www.diyaudio.com/forums/group-buys/302859-xrk971-pocket-class-headamp-gb.html
Underside:
Only top quality components are used.
Measured HD:
Measured frequency response and THD as function of frequency:
How does it sound? Well, despite its dimunitive proportions, there is no shortage of performance. Simply one of the best sounding headphone amplifiers I have heard.
I'm all good with different amps sounding different, but once again a fundamentally flawed comparison test.
Inverting throughputs, level changes in DSP, RMS level differences, conversion to MP3, no proper/solid conclusions can be drawn, ....IOW a huge waste of time.
Good try xrk971, but you need to do better.
Dan.
Inverting throughputs, level changes in DSP, RMS level differences, conversion to MP3, no proper/solid conclusions can be drawn, ....IOW a huge waste of time.
Good try xrk971, but you need to do better.
Dan.
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Not sure inverting throughout will have impact on this particular sound clip. RMS level variations noted but how much variation are we talking about? To me, I could not hear audible level difference but I hear other aspects like articulation, sibillance, bass impact etc.
The title is blind audition. If you were to go to a high end audio showroom (if the place even had 8 amps for you) and ask the proprietor to bring out 8 headphone amps laid out for you so you could sit there and plug in your headphone and listen and compare - are you going to touch the volume knobs as you listen? Sure you are. I would suggest you adjust the volume up and down for each track for each amp if you wish. Whatever is comfortable and good sounding to your ears. Certainly 8 different amps from different manufacturers won't come with the same gain and calibrated volume knob accurate to 0.1dB. It's all context - are we doing a scientific double blind ABX test? No. We are auditioning amps and asking which has a sound you find pleasing. A very different context than ABX testing.
Do you think going to a listening room to hear and sample 8 amps with your own headphones a waste of time? Then don't go.
The title is blind audition. If you were to go to a high end audio showroom (if the place even had 8 amps for you) and ask the proprietor to bring out 8 headphone amps laid out for you so you could sit there and plug in your headphone and listen and compare - are you going to touch the volume knobs as you listen? Sure you are. I would suggest you adjust the volume up and down for each track for each amp if you wish. Whatever is comfortable and good sounding to your ears. Certainly 8 different amps from different manufacturers won't come with the same gain and calibrated volume knob accurate to 0.1dB. It's all context - are we doing a scientific double blind ABX test? No. We are auditioning amps and asking which has a sound you find pleasing. A very different context than ABX testing.
Do you think going to a listening room to hear and sample 8 amps with your own headphones a waste of time? Then don't go.
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To really do this test or audition the level on the amps have to be set to the same db with a test tone.
As soon as you touch the volume knob all bets are off....
Just cranking the volume up and down on all these amps to see if you can hear differences is absolutley insane to me, but hey its fun for some I guess.
Alex
As soon as you touch the volume knob all bets are off....
Just cranking the volume up and down on all these amps to see if you can hear differences is absolutley insane to me, but hey its fun for some I guess.
Alex
Again, I ask you if you go to a store and audition amps, is store owner going to preset the volume on each amp exactly the same for you using a calibrated test tone and SPL meter and then say don't touch the volume!
My vote is cast. Thank you X for a very interesting comparison, no matter how flawed others might think it is. It was not an easy comparison for me. Almost no difference for me between the 3 best sounding clips (based on my perception using my own gear of course) and it is was difficult to choose a single winner. The most notable differences I found was in the clarity and definition of the bass and kick drum, cymbals, and the very highs of the vocals. I would like to believe that on some clips the vocals sounded warmer to me.
This is a diy forum. How would I choose my next diy amp? Probably based on the hype and subjective perceptions of others (called reviews), which is also based on comparisons. I bought my headphones online because I simply cannot walk into a shop to compare Sennheiser with Grado with AKG with Beyer etc. I had to rely on the reviews of others. How privileged we are to have a comparison like this between 7 diy headamps – all very highly praised (based on comparisons I presume). I bet many would love to see a comparison between all the Nelson Pass amps. Even Mr. Pass himself compared his amps (I saw a list somewhere), but do you trust that? How flawed was that comparison?
Thank you again X – I love what you are doing and your contributions to this forum for others like me, to learn and to perceive even more. Looking forward to see the results of all the subjective perceptions out there!
This is a diy forum. How would I choose my next diy amp? Probably based on the hype and subjective perceptions of others (called reviews), which is also based on comparisons. I bought my headphones online because I simply cannot walk into a shop to compare Sennheiser with Grado with AKG with Beyer etc. I had to rely on the reviews of others. How privileged we are to have a comparison like this between 7 diy headamps – all very highly praised (based on comparisons I presume). I bet many would love to see a comparison between all the Nelson Pass amps. Even Mr. Pass himself compared his amps (I saw a list somewhere), but do you trust that? How flawed was that comparison?
Thank you again X – I love what you are doing and your contributions to this forum for others like me, to learn and to perceive even more. Looking forward to see the results of all the subjective perceptions out there!
That still doesn't change the fact that listening comparisons without matched levels quickly yield skewed results. Heck, I bet pot-related channel imbalance may be enough to throw things off in some cases, after all it doesn't take more than about a 0.3 dB difference to be audible over headphones.
If need be, this could be quickly fixed by also recording a short calibration tone. Doing so would also indicate channel balance.
...and that's why I don't go to stores to do this type of analysis...
I take them home calibrate the amp with an SPL meter and do real comparisons....
Most people that walk in to a audio store are3 listening to speakers in a large room and for the most part the amps do little in this chain unless the amp is grossly underpowered etc...very few if any audio stores in our area have headphone amps.
That said your exercise is indeed fun but just not really well.....accurate?
Alex
I take them home calibrate the amp with an SPL meter and do real comparisons....
Most people that walk in to a audio store are3 listening to speakers in a large room and for the most part the amps do little in this chain unless the amp is grossly underpowered etc...very few if any audio stores in our area have headphone amps.
That said your exercise is indeed fun but just not really well.....accurate?
Alex
It is impossible to get a perfect equal SPLs when the frequency responses are not all flat. Distortions will produce peaks. But the real problem is when the listener is not aware of this psychological effect. Better of course, if the listener understands what is accuracy, what is dynamic/transient, what is distortion.
But we need to accept and understand that most people put their priority in bass/transient performance over distortion and accuracy.