All matters Quad!

My findings and maybe it'd be better to create another thread for this...

The 33 is clean but severely band limited *deliberately* to get the best safest use of a 303, which does funny things below 30hz, especially into 57 speakers.. Dada updated with BC155 transistors too running at the higher voltage rail, mine sounds very good if a little bright (even with the output buffer lf filtering 'relaxed' a little).

The 44 and 34 both had significant changes (44 especially) in their lives and the benefits were audible (44 especially). The typical 34 is rather 'foggy' and 'lack lustre' to me when passing music with any percussion in it. Dada do some excellent updates involving op amps and caps, Another 34 tweak was to raise the line input impedances which helped, but the gain went down. Late phono socket equipped 44's were pretty good and very versatile and up to naim standards by then I feel (memories though).

I have copy of HFR with a review of the 66 system when it came out. Noel Keywood. he liked it but then he did have a thing for QUAD anyway. I could not imagine ever being able to afford it at the time but I did like the look of it:

It’s lovely. I always had a thing for the looks. Sits well with a 606 on a quad stand too.

I tried reading up to see if I could follow, but there was nothing simole enough for me. I have heard layman’s explanations before and I remember that it’s a two stage amplification circuit that’s meanstto overcome crossover distortion. It’s how it does it that I can’t find a good explanation of.

My old Crowns have an AB circuit as a driver stage, the output devices being switched off until needed. The result is a top notch pro amp which barely gets off stone cold when on for hours, uses local feedback loops which apparently is good for sonics and which have shown incredibly long tough and reliable lives bar the odd cap here and there.

I've no real idea how different the Current Dumping circuit is (maybe they're not related at all) but again, the driver stage does all the 'low volume' stuff and the output 'dumpers' I understand only kick in when necessary. It's obviously more complex than that and today, not really necessary as modern transistors are so much more capable apparently, but the highlights have really been the 606 'family' and the pro 500 models. Good 405-2's can entertain too but both of mine needed several hours to remove a very slight 'sting' from the high frequencies (about half an hour with the power hungry ATC20's which made my second 405-2 almost cook itself )

Quad came up to date with the 77 and derived 99 series systems. These amps were straight AB designs and still sounded lovely (maybe the preamp sections were sexing it up a touch. Whatever, the sound of the 77 amps was always atmospheric, basically sweet and 'musical' but with drive and definition if there originally and definitely not soft and lush as my description may indicate. Loved 'em to bits at the time.

Listening with my eyes, I found the 606 a bit much to take, purely on appearances! the Elite QSP beefed the visuals up a bit and the Artera version looks cute when powered (and a shinier 606 breeze block when switched off). Since these amps were never intended to be put on show, it obviously didn't matter.

I'm trying to find the model name (prestige?) but Quad made a large stereo power amp - 200WPC+ into 8 ohms that was an AB design and apparently it's superb (HFW tested it but I think I chucked the mag itself recently).

Compared to the likes of macca's Krell and my D-150, I'd say the bigger Quad power amps have slightly more of a velvet coating over the undeniable iron fist underneath, so may sound slightly 'darker' perhaps. These differences are very small and must admit my listening session with the Artera pair wasn't so different in 'feel' to the Sonneteer Alabaster my dealer pal connected immediately after and I loved them both.

I'd also like to hear the new version of the Vena, which is very well priced, solid in feel (not tinny) and actually not expensive for what it does.

Lovely looking 909 for sale on AOS at a very fair £460 delivered. Iron fist in velvet glove amplification!