S.E.X. as preamp feeding Quad II classic MonoBlocks?

[pistachio]

Hi all, I'm interested in ordering the SEX 3.0 kit. Primary reasons will be as headphone amp (easy drive Oppo PM-3) and as amp to drive some 92dB speakers in near field home office setup.

However, I have a pair of Quad II that never get used because I lack a preamp for them. I've searched the forum and it seems people have had success with using the S.E.X as a preamp by using the headphone out.

Would this also work with the Quads?
I don't know enough about this to understand possible impedance matching issues etc.
Advice is appreciated, thanks.
Pete.

[Paul Birkeland]

Yes, you can use the SEX as a preamp.  If you have the super old ones that don't have RCA jacks, you'll need to make some cables or modify the amps a little so you can connect them to the SEX amp. 

You'll also find that vintage power amps have tons and tons of gain, so using a pair of Harrison Labs -12dB attenuators at the input of each amp so they aren't so sensitive.

[pistachio]

Thanks Paul, that sounds good. Yes, I have the Jones plug to rca adaptors. Also the amps have been checked over and original GEC valves tested well etc. Hence it’s a bit of shame theyve been just sitting on the shelf.
Cheers, pete.

[Deluk]

As an extra to this, what would be the most suitable BH pre for the Quad II's? Of course the BeePre2 is fine but the big jump in price from a Moreplay has to be considered. A long time ago I asked about using my Crack with my Quad II's and it was agreed that it would be possible if attenuators were used. Would attenuators be needed with a Moreplay?

[Paul Birkeland]

The Moreplay and the BeePre have less gain than the Crack and SEX amp do, so the needs for attenuators won't be as significant.