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Audio Research SP9 Circuit Diagram HELP!

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T

Toaster

Member
Joined 2004
Hi, I have the circuit for the SP9 MK1- ARC thoughtfully include it with the manual. Bear in mind though that some of the fets are ARC own brand and equivalents are not listed, so it depends what you're trying to do as to whether the circuit'll do you any good...
 
V

Valde

Member
Joined 2007
mkI

Hi Folks and mainly Toaster,

I'm in the same situation for the need of a circuit diagram for a SP9 mkI.

The ARC dealer in Denmark won't handover a sheet to even if I pay for it.

My ARC SP9 has a modified phono section. The 2 big transistors (in a TO-220 housing) in the mid of the phono stage has been removed a modified with one EC91 in each channel. Somebody claims that this is in the powersupply section of the phono section but I doubt. So I will be very pleased to see a circuit diagram for the SP9 (the original version, but a later version will also be apreciated ;)

Regards
Valde
 
L

Luke

Member
Joined 2001
which pre then

brett and analog_sa, if you were going to build a balanced valve pre, something with some gain and not rare silly price and availability tubes, which would you build?
My understanding is the arc ls25mkII is quite a good pre amp, but then that was reviews not listening.

cheers arthur
 
Brett

Brett

Member
Joined 2002
Re: which pre then

Luke said:
brett and analog_sa, if you were going to build a balanced valve pre, something with some gain and not rare silly price and availability tubes, which would you build?
Click to expand...
Assuming no phono pre reqd, a balanced version of my 12B4 with siutable OPT or
http://www.raleighaudio.com/Figure_18.jpg

...but with ECC99, 6H30 or 6H6N and OPT adjusted accordingly. EL84 in triode with a sufficient amount of current would also be nice.

It all depends upon how much gain you want.

Without the input trans, Allen Wright's RTP3C front end could be added with a little tweaking of RIAA components to give phono capability and would come close to the last full function pre I built, and is similar to the next one I have planned. All my vinyl is stored at the moment and will be for some time yet, so it's way down on the to-do list.
 
V

Valde

Member
Joined 2007
caliban said:
V,

I resent the schematics (6 pages) on March 2, 6:20 A.M. EST (USA). If you do not receive the email this time, let me know and we'll figure something out.

Make sure your spam filter does not bury it, sender is flatsixxx.
Click to expand...


Caliban, this is very strange! I have not received your mail. Eventhough that I had received other emails this day ?!? I'm not aware that I have a spam filter, if so, it's administrated by the ADSL operator which is DK's biggest operator on this field and should manage this kind of files...

Do you send it direct to flemming.skov@nypost.dk ?
Thanks for your efford in advance...
 
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