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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
mozartfan
2,143 posts
 
AR SP8, has 4 12AX7's , 1 AT7 and 1 6922.
yeah you could swap  a  pair of 12AX7's, and employ   12AU7's in that circuit.
have Richard remod it  for you

https://www.arcdb.ws/model/SP8


bdp24's avatar
bdp24
9,788 posts
 
I used to have an Audible Illusions Modulus 2 pre-amp, the line stage of which provides 30dB of gain! Did Art Ferris ever update his design?
imhififan's avatar
imhififan
2,183 posts
 
If anyone interested, this is the schematic of the Puresound A30

http://lampizator.eu/AMPLIFIERS/CHINA/bewitch%206550/IMG_5576.jpg

IMO, leave the Puresound A30 and AR SP8 stock, just simply set the Puresound A30 volume knob at 12 or 1 o'clock is the best solution.

audite84
110 posts
 
OP, 

If the Puresound A30 is to be used as an amplifier (i.e. driven by a separate preamp), its volume control should be fully turned up. You are definitely degrading the signal if it's at 1 o'clock.

As mentioned, given the mismatch between the AR and the A30, it would be best for you to use the A30 as it is, an integrated amp.

Tube rolling is one thing you may look into if you're looking for a particular sound. Start with the driver tubes if you wish. 
tenoris OP
15 posts
 
@georgehifi thank you very much for your advice. If you take it to a technician, you could also complete the operation by reducing the gain at any of the Puresound inputs.As I have already mentioned, I have followed the manufacturer’s instructions, which in the Puresound instruction book says not only that it can work as a power amp but that it can also do it in an excellent way, textual words.

@audite84 with the volume of the Puresound at maximum it continues to work, so I do not understand why if we put it at 1 there is more degradation of the signal. It is true that if the manufacturer indicates this, this reason must exist, except that it is written thinking that most of the current preamplifiers need more volume.
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