Quad update

[Idlewithnodrive]

To these ears, the306 just sounds too bouncy, too mid forward in presentation; almost like it's trying too hard to impress.

The 303 is very musical but in a 70's veiled sort of way.

The 405-2 almost as musical but more open and a bit more detail and control at the frequency extremes, although none of the three could be considered dynamic IMHO

[Barry]

Although Quad tried to make their first solid-state amplifier, the 303, 'universal', it was optimised for use with the Quad electrostatic speakers and the combination of the two is especially fine, as I reported a while back.

Of the current dumping designs, the 405, 510, 520, 306, 606, 909, my own experience is with the the 405, 510 and 520. One of my 405-2s has been upgraded to NET level 3, with dual-mono power supplies. Another pair have been 'monoblocked' by tubehunter with the circuit modified to Keith Snook level 3, precision high-tolerance components fitted in the bridge circuit, as well as higher rated power output transistors and the power supply diodes replaced by 35A bridge rectifiers. Some of the resistors around the input IC have been replaced with Z-films. All of these modified Quad 405s sound excellent when feeding Quad 57 speakers.

As do the Quad 510 monoblocks, both these and the monoblocked 405s were successfully demonstrated at the last MiBO with Firebottle's Quad 57 speakers. At the end of the evening we played the Who's "Don't get fooled again" at a loud level - no lack of dynamics there, the Quads can boogie with the best of them!

[DSJR]

Personal subjective comments these, but I remember back in 1992, when I first forayed into ATC territory with the hideously inefficient SCM20's, I used a freshly updated 405-2, in stock Quad form and using replacement standard spec supply caps. Poor thing ran very hot indeed at the volumes I played at (I used to be a 'HiFi hooligan'). I replaced it with the stereo AVI power amp rated at 80WPC and although maximum volume was barely different in all honesty, the AVI ran barely warm and sounded at least as good into the ATC's. The AVI mono's though, were comfortably louder and better all round I felt and they sometimes come up on eBay for under £500. Servicing shouldn't be difficult either as the circuits were simple as I recall.

[Idlewithnodrive]

Although Quad tried to make their first solid-state amplifier, the 303, 'universal', it was optimised for use with the Quad electrostatic speakers and the combination of the two is especially fine, as I reported a while back.

Of the current dumping designs, the 405, 510, 520, 306, 606, 909, my own experience is with the the 405, 510 and 520. One of my 405-2s has been upgraded to NET level 3, with dual-mono power supplies. Another pair have been 'monoblocked' by tubehunter with the circuit modified to Keith Snook level 3, precision high-tolerance components fitted in the bridge circuit, as well as higher rated power output transistors and the power supply diodes replaced by 35A bridge rectifiers. Some of the resistors around the input IC have been replaced with Z-films. All of these modified Quad 405s sound excellent when feeding Quad 57 speakers.

As do the Quad 510 monoblocks, both these and the monoblocked 405s were successfully demonstrated at the last MiBO with Firebottle's Quad 57 speakers. At the end of the evening we played the Who's "Don't get fooled again" at a loud level - no lack of dynamics there, the Quads can boogie with the best of them!

I too owned those monoblocks briefly and although they were, undoubtedly, very good, to me they just seemed to lose their connection to the music, erring more towards hi-fi. So, I went back to a single 405-2.

It seems we all hear things differently, or listen for different things.

[Barry]

Interesting. That either means you don't like the improvements suggested by Keith Snook (inter alia), or you like two-channel amplifiers which share a common power supply.

When I demonstrated the 405 monoblocks at MiBO, one of the comments made was they did not sound clinical or 'hi-fi', but natural and involving. (They were used with Quad 57 ESLs)

Anyway the later stock 405-2s are very good - I have one. And as you say, we all hear differently - it would be boring if we were all the same.

[Macca]

At MiBO we used a number of different power amps with the QUAD 57 speakers, the presentation was noticeably different in all cases, and people's likes varied. Personally I erred towards the sound made by Barry's QUAD monoblocks, I thought they most exploited the unique advantages of the ESL speakers; but I can understand why other's preferences differed.

[Gordon Steadman]

To these ears, the306 just sounds too bouncy, too mid forward in presentation; almost like it's trying too hard to impress.

The 303 is very musical but in a 70's veiled sort of way.

The 405-2 almost as musical but more open and a bit more detail and control at the frequency extremes, although none of the three could be considered dynamic IMHO

Does this mean that reality changes according to when something is manufactured?

Every time I hear what is described to me as a dynamic amplifier, I end up covering my ears in protest at the screaming, harsh and unmusical sound. The 303 and 57s just communicate the music in a no nonsense way without feeling you are listening for what is wrong with the hi-fi.

I do get fed up with this received wisdom about Quad gear being safe, cuddly whatever.

[Pieoftheday]

Does this mean that reality changes according to when something is manufactured?

Every time I hear what is described to me as a dynamic amplifier, I end up covering my ears in protest at the screaming, harsh and unmusical sound. The 303 and 57s just communicate the music in a no nonsense way without feeling you are listening for what is wrong with the hi-fi.

I do get fed up with this received wisdom about Quad gear being safe, cuddly whatever.

My 306 wasn't bouncy or forward, it just made the speakers make music .I found it character-less, brill amp

[Idlewithnodrive]

I do get fed up with this received wisdom about Quad gear being safe, cuddly whatever.

I didn't say it was safe or cuddly Nodrog, as you could probably summise by the fact that i have kept my 405-2 above all other amps I have owned. I really rate Quad gear and have just explained how the relevant models stack up to these ears.

[Arkless Electronics]

For what it's worth I once had (still have the boards somewhere) a 405 mk1 in which I replaced the op amp with a much better one, improved the supply to the op amp, replaced various capacitors etc and disabled the protection circuity... from what I remember it was a bloody good amp! No lack of dynamics, no "pipe and slippers" at all!