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AR SP8 mk2 high output volume

Hello everyone, thank you for accepting me in this group. I have my AR  SP 8 mk2 preamplifier and I would like to know your opinion and if you consider its high output volume a problem with this power amp. Problem is the volume control is too low,  Very sensitive amp. I can't use much volume control.Does this affect the signal quality or is it just a drawback?I just want to know if it's something I need to worry about.

here I put the specifications of the power amp Puresound A30
ower output (Class A operation) 30 Watts/ch Ultra Linear, 18 Watts/ch Triode Coupled
Frequency Response 20Hz - 20kHz -0.25 to -0.3 dB
THD 0,3%
Input Impedance 100 KOhm
S/N ratio 88 dB
Input sensitivity for 0dB 100 mV
Power Consumption 260 Watts
Net Weight 28 Kg
Dimensions (mm) 436 W x 360 D x 190 H
Inputs 3. Line Level
Outputs 4 & 8 Ohm
tenoris
tenoris OP
15 posts
 
Thank you all very much for these valuable contributions.
@atmósfera the one hand it seems good news that the passive attenuator of the A30 does not degrade the signal, but what I do not understand is your question because it seems that the AR is not fulfilling its function as a preamplifier. I gather this because you ask me strangely if I notice any improvement. Is it that the AR is not fulfilling its function like any other preamplifier?
The Puresound as integrated works quite well but when I put the AR I notice a plus in terms of presence and forcefulness of the music
atmasphere's avatar
atmasphere
11,807 posts
 
when I put the AR I notice a plus in terms of presence and forcefulness of the music
OK. I asked simply because with a high level signal like a CD player I would not have expected adding additional circuitry would have helped out.
mrdecibel
3,063 posts
 
It seems the integrated amp is similar in design, to a power amplifier, connected to a passive unit ( this A30 amp design, is becoming very popular ). What the OP is saying, imo, he does not like passive, as much as the AR's tube line stage, and prefers the extra gain, like many people, that do not like passive. It just so happens, the amp has it's own volume control ( no different than many pro amps having input attenuators ), but still going through a preamp, with gain, or even a passive device, with multiple inputs ( something I am very accustomed to ). Enjoy !, and be well....
georgehifi's avatar
georgehifi
10,312 posts
 
This just keeps going around in circles, if you don’t like the sound when it’s used as an integrated, change the source to one you like, instead of coloring it with that premp, and then having your problem of way too much gain.

Just look at the specs of the A30, it’s at FULL POWER already with ONLY 0.5v (500mV) input from a source. Most sources today put out well over 2v!!!

So just use it as is with it’s own passive volume control, and remember Nelson Pass saying to you ("psychological need" to turn it up more) than when the AR pre is in and then sell it.

Nelson Pass,

“We’ve got lots of gain in our electronics. More gain than some of us need or want. At least 10 db more.

Think of it this way: If you are running your volume control down around 9 o’clock, you are actually throwing away signal level so that a subsequent gain stage can make it back up.

Routinely DIYers opt to make themselves a “passive preamp” - just an input selector and a volume control.

What could be better? Hardly any noise or distortion added by these simple passive parts. No feedback, no worrying about what type of capacitors – just musical perfection.

And yet there are guys out there who don’t care for the result. “It sucks the life out of the music”, is a commonly heard refrain (really - I’m being serious here!). Maybe they are reacting psychologically to the need to turn the volume control up compared to an active preamp.”

Cheers George

georgehifi's avatar
georgehifi
10,312 posts
 
BTW I do not recommend tampering with the feedback resistor- such things can lead to oscillation

tenoris OP
This is why I say get a tech (not yourself) to disconnect the Alps passive, change the gain with the feedback to half of what it is, as he will scope it and compensate for stability.
And then once that is done you can use your AR preamp which you are so insistent on using, with the volume up around or over 12 o’clock. And this is what you searching for.

Cheers George
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