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user 49612
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For similar money you'd get real performance. Furman is utilitarian and useful. A Puritan is end game hifi. Puritan on a dedicated line. There is no better power
ejspain
Well-known member
Send me some info bud
The hum is so low that its not even noticeable. Why worry about that? That makes no sense at all. It practically non existent on my speaker. Not sure about ejspain's, but i didnt even know mine was there.
Heres one for $2300. I paid about $600 for my Furman. Big price difference. A bit hard to compare those two.
https://jaguaraudio.com/product/psm156-power-conditioner-by-puritan-audio-laboratories/
I can't hear any hiss from the C18 - what frequency are we talking, above 12Khz it might explain it.
If one can hear hiss, then a sensitive mic should be able to hear it also.
Try as I may, I just don't hear any hiss from my C18 when using any of my latest amps. So I connected an old Onkyo and then got hiss.
The plot is using REW's RTA to record a mic placed a few millimeters from the grill of the C18. The volume level of the processor is at maximum for when the amp is on and using the HC-1, but not at max when using the Onkyo. The gain of the HC-1 is 29dB, I don't know what the gain of the Onkyo is but I don't think that matters since it obviously produces hiss. I included 4 traces because I did one set of measurements (amp on, amp off) last night, and the other set this morning, so this is just to show a somewhat repeatable environmental noise level. The Cicadas and birds weren't making any noise late last night or yet this morning, so the noise floor looks consistent. As noted in the legend the Onkyo when it's on is the purple trace. Don't know if you can notice it or not, but it's the one with all the tall peaks.
Try as I may, I just don't hear any hiss from my C18 when using any of my latest amps. So I connected an old Onkyo and then got hiss.
The plot is using REW's RTA to record a mic placed a few millimeters from the grill of the C18. The volume level of the processor is at maximum for when the amp is on and using the HC-1, but not at max when using the Onkyo. The gain of the HC-1 is 29dB, I don't know what the gain of the Onkyo is but I don't think that matters since it obviously produces hiss. I included 4 traces because I did one set of measurements (amp on, amp off) last night, and the other set this morning, so this is just to show a somewhat repeatable environmental noise level. The Cicadas and birds weren't making any noise late last night or yet this morning, so the noise floor looks consistent. As noted in the legend the Onkyo when it's on is the purple trace. Don't know if you can notice it or not, but it's the one with all the tall peaks.
ejspain
Well-known member
Does this mean the moral of my story is, my Parasound A31 is producing the noise eventhough my specs look good?
S/N ratio:
112 dB, input shorted, IHF A-weighted
Total harmonic distortion:
< 0.2 % at full power
Input sensitivity:
1 V for 28.28 V (THX Reference)
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Im using this amp on mine:
https://emotiva.com/products/hc-1
I have an extremely low volume voltage hum I think. It's very slight. It's so hard to hear, with my ear right up against the speaker grill, that I had to turn off the stereo to verify. I have tinnitus and thought it might be that. My tinnitus is louder.
https://emotiva.com/products/hc-1
I have an extremely low volume voltage hum I think. It's very slight. It's so hard to hear, with my ear right up against the speaker grill, that I had to turn off the stereo to verify. I have tinnitus and thought it might be that. My tinnitus is louder.
I doubt it's the A31. Could be anything in the chain.
ejspain
Well-known member
Woo that's a relief because I really love this amp.
My HC-1 makes mechanical noise that I can hear when my ear is placed on the top. Put your ear on the HC-1 and see if that's what you're hearing.
To be certain that no mechanical noise would affect the tests I covered the amps with absorption panels so they were totally muffled, and the results can be seen in the plot with the three traces all about the same for when the amps are off, and the HC-1 is on. It's just the Onkyo when on that's the outlier with the noise coming through the speaker.
edit: A friend has a McIntosh amp that makes mechanical noise that was pretty loud when he had a plasma tv. But since replacing that tv with a non-plasma that noise went way down to what I would call normal tranny noise.
My Krell Duo makes a tiny bit of transformer mechanical noise that I can only hear with my ear touching the top of the amp, but as soon as the fans start spinning that tiny noise is masked by the fan noise, and again, the fan noise is only heard by my ear touching the top of the amp.
My old Krell is "virtually" dead silent, and it's got the biggest transformer of any of my amps. It makes so little mechanical noise, but does make noise.
My tube amps' trannies also make mechanical noise, and they also produce a very small amount of hiss when I used them with the 13A speakers. I had to place my ear so close to the stat panel to hear it that I got a zap when a hair must've touched the innards of the stat. Not recommended to place an ear on a stat panel.
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Gordon Gray
Well-known member
There are many PLC's on the market. They will all impact the system sound. The question is which model is affordable to you and impacts the sound in the most positive manner. And there is only one way to make that determination. Good news is there are numerous purchase options with a money back guarantee.
Gordon Gray
Well-known member
Hi there,
Have you tried the Audioquest and Shunyata Research alternatives? Given your comments about Furman, I do not understand your statement that it is a waste of money. Can you elaborate?
Leporello
Well-known member
Note that tranny noise is something not having an absolutely pure sine wave can definitely impact. A lot of people bark up the AC line noise tree when in my opinion it's not justified (and I think a hiss is something you cannot blame on line noise), but mechanical noise is where it can make a real, repeatable difference.
p.s. Thanks for your efforts in trying to correlate what people are hearing with actual measurements.
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Leporello
Well-known member
Doesn't have to be the A31 per se. My JC-1 has above average voltage gain. For me this means that with the P-7 in theater bypass mode and the Outlaw 975 in the loop, a ground loop problem centered around the 975 is exaggerated and I have no good way of trimming it down.
Leporello
Well-known member
Hasn't happened to me yet, but you could use a stethoscope.
Leporello
Well-known member
I thought that was caused by a cow.
Consider using different amplification and see if you still have the hiss that bothers you.
