Phantom 1.4.1.12 measurements

[streamy]

Thanks for posting the curves and your interpretations. You show very nicely how the Phantom with Spark behaves in the normal listening SPLs. The volume control between 35 and 60 is linear (i.e. logarithmic), which is nice. Also there is no change in the frequency response. I see from your recordings in plot 2 that you went fom 50 up to 80 with a lower input signal. As I hear a steep volume progression for volumes between 60 and 75 (on silver phantoms) could you display these curves in a plot?
Also an eventually built-in loudness effect on lower volume (volumes 10-35) could be eventually measured. Did you do such measurements? Also at these lower volumes I hear a lower progression than between 35 and 60. Could your measurements confirm this?
Again, many thanks for sharing your plots!

[Confused]

The current update as per previous updates has often elicited various comments about the change to sound quality and to the behaviour of the Spark volume control.

The latest update has found me with the time and inclination to perform some simple measurements.
I hope they prove useful and provoke discussion but, hopefully, not argument.  They are, after all, based on my devices, positioned in my environment were they are located for normal listening.

Thank you for taking the time, this is great!

Do you have any thoughts about what is going on in the 100-200hz area? Is that where the crossover to the side woofers is?


Sent from my iPhone using Tapatalk

The dip in the 100 to 200Hz region looks absolutely typical of the kind of bass null that you get due to room interaction.   You could try a whole range of different speakers in the same room and the effect would remain to a large degree.  This might be hard to believe with the microphone only 30cm away from the Phantom, but even here, a supprisingly large percentage of what the microphone will pick up is sound that has reflected off the walls, cieling etc.  If you were keen enough, you could get a very long mains extension cable and try the test again in the garden and I'm sure this dip will vanish.  (do not try if it is raining)   They are great fun these graphs, and can be useful in setting up a room, speaker placement, trying room treatments etc.  Also, they can lead to obsession, paranoia, insanity.  (I thought my system sounded great, but I now find I have a bass null, I must fix this!  I MUST!  etc.)

[sleach]

They are great fun these graphs, and can be useful in setting up a room, speaker placement, trying room treatments etc.  Also, they can lead to obsession, paranoia, insanity.  (I thought my system sounded great, but I now find I have a bass null, I must fix this!  I MUST!  etc.)

Ha ha! Yes, you are right to point that out - I was on the cusp of ordering another Umik (I've bought and sold two already!)


Sent from my iPhone using Tapatalk

[Confused]

They are great fun these graphs, and can be useful in setting up a room, speaker placement, trying room treatments etc.  Also, they can lead to obsession, paranoia, insanity.  (I thought my system sounded great, but I now find I have a bass null, I must fix this!  I MUST!  etc.)

Ha ha! Yes, you are right to point that out - I was on the cusp of ordering another Umik (I've bought and sold two already!)


Sent from my iPhone using Tapatalk

Ah Mr sleach, I see the hifi induced madness has struck you down already, most excellent!  This is in fact a splendid place to be, much better than normal reality.

[alandbush]

Alandbush, by using minidsp, I assume that you are using optical in to the Dialog if you are running stereo, or directly to a single Phantom? 

I can't figure out how one can use miniDsp if one was using Spark to steam online services such as tidal or using Spark to play music in one's own server.

MtnGuy

You are correct to assume the use of optical in, although I avoid using the 'suspect' Dialog connection and I play music through the Auralic Aries to the MiniDSP.

I don't know how you could currently apply real time EQ to a Spark stream

[alandbush]

Thanks for posting the curves and your interpretations. You show very nicely how the Phantom with Spark behaves in the normal listening SPLs. The volume control between 35 and 60 is linear (i.e. logarithmic), which is nice. Also there is no change in the frequency response. I see from your recordings in plot 2 that you went fom 50 up to 80 with a lower input signal. As I hear a steep volume progression for volumes between 60 and 75 (on silver phantoms) could you display these curves in a plot?
Also an eventually built-in loudness effect on lower volume (volumes 10-35) could be eventually measured. Did you do such measurements? Also at these lower volumes I hear a lower progression than between 35 and 60. Could your measurements confirm this?
Again, many thanks for sharing your plots!

The lower input signal measurements were an attempt to record volumes above 60 to determine if the volume behaviour changed as you suspect. However, the SPL responses were practically equal to the previous offsetting for the physical volume, I.e. SPL response for 60 @ -12dB was equal to 80 @ -32dB.

Nb - I could not advance beyond 60 without clipping and I thought the ambient noise floor may have interfered with lower volumes. However, I think I'll try lower volume measurements targeting below 200Hz.

[AlanD]

Do you have comparisons with your previous speakers? This is great work, thanks!

[alandbush]

Do you have comparisons with your previous speakers?  This is great work, thanks!

Unfortunately no, but they (ATC 50ASLs) did not produce bass at the level or depth of the Phantoms.

[alandbush]

As per a request, I attempted more measurements of the SPL response at Spark volumes of 10-35 to determine how the lower bass frequencies volumes are adjusted.

Caveat - At this volume level there is little output that I can hear and it is approaching ambient noise levels and can be affected by external sounds. The mic may also be reaching it abilities.

Each volume sweep is at least an average of 5 with many more taken the lower the volume, though I am sure the result could change if performed again.
The resulting average has then had 1/6 smoothing applied to ease the comparison.

I would tentatively say that, around 25Hz, it appears the volume stops dropping uniformly by 5dB.

[attachment=753]

[AlanD]

Wonderful work. I am curious if the audible changes with the new firmware will be revealed in pink noise sweeps rather than a log sweep. It would be interesting to measure the Phantoms with pink noise also as baseline and then retest with the next firmware. Are you able to hear the differences in sound quality with your room?