The scratchy pot is still there......rather annoying in a brand new high end piece, I certainly value your opinion and unless changing it out poses ancillary risk I think its prudent to get fixed under warranty....seeing as I found an auth Parasound service within 3hrs (which I don’t consider too far to drive) ...plus it’s the only high end showroom near me and I’ve never been there!
I suppose they could do a diagnostic on it while it’s there to see if it’s in spec.
Bob
If you mean microphones positioning and further mixing, there is an effect of course.
Re pot - there must be no DC across the pot. Otherwise, blue Alps is extremely reliable and lasts ages. I have many of them in operation 20 years without any problem.
A second upwards firing tweeter adds air and presence..my new listening space has a sloped ceiling in the wrong direction for it to work I think.....I’m gonna experiment later.
😎 is that what the ‘scratch’ is ? DC across where it doesn’t belong?
yes. If there is a coupling cap in series with pot and it become leaky over time, it is the cause of the scratchy pot. This is esp true of bipolar or electrolytic types. Like-wise if there is a dc servo which is not functioning correctly, the dc offset into pot will cause similar noise problem. Check for dc level to the pot... should be zero.
THx-RNMarsh
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Alps appears to have changed its manufacturing. Of course, we used Alps pots for about 40 years, BUT things change.
MMB just figure a way to UPS your receiver to the repair station. Be sure to get permission first.
MMB just figure a way to UPS your receiver to the repair station. Be sure to get permission first.
Didn´t we already discuss this "heigth issue" a couple of weeks ago?
Anyway, if both channels reproduced the same signal we usually perceive it as a virtual sound source in the frontal median plane. But this virtual sound source (normally) not only appears as more diffuse but also as being elevated in the vertical plane if compared to a signal coming directly from one of the speakers.
Another variable are the so-called "Blauert´s directional bands" where signals in dependance of their spectral content are perceived as coming from different directions.
The most important variable imo is the often mentioned effort of our brain to construct from sensory input (including all possible cues) a internal representation that is most compatible to our experiences.
See for example the above mentioned elevation of the frontal midplaced virtual sound source. If a singer is placed at this position of the stereo basis, it fits to our experience of a singer standing (often) in the middle of the stage and therefore amplifies the impression of a vertically higher placed sound source.
It illustrates why listening experience (with real soundfields) helps in perceiving depths of image, spatiality in general when listening to a replay over a conventional (two channel) stereo setup. Something - as cited earlier -that the inventors of the system in the ~1930s already knew.
It explains (again imo) at least to a degree why the appreciation for a certain record can range so wildly from listener to listener. (Intersubject variability is high).
A european label proposed a so-called 2+2+2 loudspeaker setup around ~2001 to enhance the 3-dimeonsionality:
http://www.swissaes.org/nl/aes_newsletter_91.pdf
(Source:Stereo,April,4/2001,32)
Anyway, if both channels reproduced the same signal we usually perceive it as a virtual sound source in the frontal median plane. But this virtual sound source (normally) not only appears as more diffuse but also as being elevated in the vertical plane if compared to a signal coming directly from one of the speakers.
Another variable are the so-called "Blauert´s directional bands" where signals in dependance of their spectral content are perceived as coming from different directions.
The most important variable imo is the often mentioned effort of our brain to construct from sensory input (including all possible cues) a internal representation that is most compatible to our experiences.
See for example the above mentioned elevation of the frontal midplaced virtual sound source. If a singer is placed at this position of the stereo basis, it fits to our experience of a singer standing (often) in the middle of the stage and therefore amplifies the impression of a vertically higher placed sound source.
It illustrates why listening experience (with real soundfields) helps in perceiving depths of image, spatiality in general when listening to a replay over a conventional (two channel) stereo setup. Something - as cited earlier -that the inventors of the system in the ~1930s already knew.
It explains (again imo) at least to a degree why the appreciation for a certain record can range so wildly from listener to listener. (Intersubject variability is high).
A european label proposed a so-called 2+2+2 loudspeaker setup around ~2001 to enhance the 3-dimeonsionality:
http://www.swissaes.org/nl/aes_newsletter_91.pdf
(Source:Stereo,April,4/2001,32)
10-4.....I’ll just drive it over (3hrs).....I would do it myself (even if it voided the warranty) before I put it back in a big brown truck!
I’ve already cleared it with Chris at parasound, just need to make an appointment in Gainesville.
I’ll be sure to have them check the DC level to the pot.
Edit....also want to apologize for getting a little OT....it started out relevant to something at some point! ; )
Bob
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MB, the usual failure mode for a pot unused for long period is oxidation of silver plating of contact tracks within the pot and emulsification/drying of contact grease.
You could exercise the pot over it's full range 50-100 times and this may clear the fault, especially if you can get some contact cleaner/lubricant inside the pot.
It is worth checking for DC on the pot over the range of rotation but this is not really likely to be the fault.
Dan.
You could exercise the pot over it's full range 50-100 times and this may clear the fault, especially if you can get some contact cleaner/lubricant inside the pot.
It is worth checking for DC on the pot over the range of rotation but this is not really likely to be the fault.
Dan.
@ Bonsai,
in a typical experiment exploring a hearing threshold of for example a single/pure tone the resulting psychometric function could look like this one:
(Stanley A. Gelfand. Hearing - An Introduction to Psychological and Physiological Acoustics, CRC Press Boca Raton, 6th Ed., 202)
Using the method of constant stimuli, level step size of 1 dB and taking 50 data points at each level. The stimuli range encompass the known or assumed hearing threshold, the different stimuli presented in random order, the participants have to answer if the stimulus was present in the according trial.
So how exactly is this chart built? I guess I'm missing something here. Close to 0% average of identifying the presence of the test tone is to me a very remarkable result. I would expect, as the level approaches the audibility threshold, the average results to saturate at 50% (pure guessing).
In the method of constant stimuli, the stimulus that is detected 50% of the time and not detected 50% of the time is considered to be the threshold, so the 7.5dB appears correct, though.
This reminds me of a QC guy that insisted op-amp noise had a normal distribution i.e. a 4nV amp had a population at 1nV.
Parasound had a run of faulty pots early on .....they said replacement is the only solution, and it’s covered under warranty.
Spoke to the shop today and they said they’ll do a full diagnostic b4 and after replacement.
Yes, despite the assertions of some, as uninformed as they are definitive, that read books instead of verifying/Listening by themselves, our hearing has a way of locating the vertical positions of sound sources. The brain uses the response curve variations of our ears between the front and back positions and bottom to high. It's less accurate than the lateral location, but it works.
Especially with moving objects. It is enough to close the water by hearing an avi pass vertically to make sure.
Not to forget that the natural reflex est to move the head in direction of the source, thet precise this localisation.
A big Japanese company had even created a 3D localization studio gear based on complex algorithms, and it WAS WORKING. Even in the headphones. i experienced this at this time with great interest.
About the PMA file, I listened to it on a large band speaker(My PC speakers), my concentric KEF and headphones: there was no question of position of speakers: punctual sources.
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Well clearly it could be in the recording if done in a certain way. Binaural recordings very obviously have height information.
Dan, the Alps pot in the Parasound integrated amp needs replacing. Most Alps pots are most probably OK.
Sorry for the " It is enough to close the water by hearing an avi pass vertically to make sure."
Automatic machine ;-(
It is enough to close our eyes, listening to a plain passing vertically in the sky, to unsure.
Automatic machine ;-(
It is enough to close our eyes, listening to a plain passing vertically in the sky, to unsure.
Your prose, reading in English, is always so charming, so poetic, and so often surprisingly illuminating, that I study each carefully. This one reminds me of S. Freud's gruff rejoinder to an impertinent comment on his cigar smoking: "Sometimes a cigar is just a cigar."
Much thanks, as always,
Chris
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