The Marco-boy main system, as of August 2020

[Marco]

It's a great choice as a back-up amp Marco (or as a main amplifier in many systems, as it's surprisingly capable).

Cheers, Geoff. Indeed... I've read lots of positive views and reviews about it, and seems that it was built very well to start with and sounds remarkably good, outperforming many modern amps up to around a grand

Marco.

[walpurgis]

Cheers, Geoff. Indeed... I've read lots of positive views and reviews about it, and seems that it was built very well to start with and sounds remarkably good, outperforming many modern amps up to around a grand

Marco.

The 'current dumping' design is a clever thing, using Class A primary amplification followed by Class B to do the donkey work. The sound has a lot in common with what typifies regular Class A SS amps, those I've heard at least. Funny thing is, I wouldn't say the same about the bigger Quads, pleasant as they can be.

[The Black Adder]

Didn't Ian have two Quad amps at some point?

Glad the SUT is working out to how you remembered it.

Coming from not owning one before, I find it a very nice difference.

Your term 'ballsy' regarding the comparison between the denon and the Lentek is spot on.

I like how the Lentek sounds. But I like the denon for its easy way of portraying detail.

The Lentek does sound more solid state, if that makes sense, but in a good way because it does sound good.

I concur regarding the amount of time the denon takes to set its pace. It doesn't take long and I find that a quick stylus brush with a carbon fibre brush sets it on its way a little quicker. I never thought that would make a difference. But, I've never used a transformer based SUT before.

I like the fact that no batteries are used too.

The denon AU-310 was introduced in 1976 and with it sounds every bit as good today playing Goa, Dance, Dub, Electro, Rock, Classical etc... That's something nice to find.

I presume this is down to the transformers being of a very high quality.

There is one thing I'd like to know regarding the Denon, though. Would it be beneficial bypassing the bypass switch on the front? I'd like to know if anyone here would be able to shed any light on that. I take it that the switch is in the signal path?



Some pics from the net.






Sent from my 9001X using Tapatalk

[Marco]

The 'current dumping' design is a clever thing, using Class A primary amplification followed by Class B to do the donkey work. The sound has a lot in common with what typifies regular Class A SS amps, those I've heard at least. Funny thing is, I wouldn't say the same about the bigger Quads, pleasant as they can be.

Yeah, that's pretty much what I've read. I like the design principles, but unfortunately it seems like Quad have suffered the same problems as other manufacturers have, over the years, and that's the quality of the products suffering due to cost constraints, and new designs going in a different direction that may otherwise be desired in order to increase profits.

That's probably why, like many other manufacturers, Quad's original designs are best. I'm not sure Peter Walker, had he he still been with us, would've sanctioned some of the later stuff, so yes it does appear to be somewhat of a 'lottery' which type of 'Quad sound' you get depending on what you're buying and the decade it was produced, but I'm looking forward to test driving this 306, as the only previous Quad product I've owned was an FM3!

Marco.

[walpurgis]

Some suggest Quad amplifiers have a 'family sound'. They don't. The 303, 405, 306 and 606 each have rather different ways of presenting music. The 606, 707, 909 and QSP etc., sound very similar to each other though. I wouldn't mind an early 909 (in black of course ) actually, it's a big softy with a laid back benign character, powerful though, but not as involving as the 306.

[Marco]

Didn't Ian have two Quad amps at some point?

Yes it was a pair modded 405-2s. He's gone back to his roots now, however, with a full Naim system and Isobariks!

Glad the SUT is working out to how you remembered it.

Coming from not owning one before, I find it a very nice difference.

Your term 'ballsy' regarding the comparison between the denon and the Lentek is spot on.

I like how the Lentek sounds. But I like the denon for its easy way of portraying detail.

The Lentek does sound more solid state, if that makes sense, but in a good way because it does sound good.

Yup, exactly, just a different 'take' on the music. It's the classic trade-off between transformers and transistors!

However, the reason that the AU-310 works so well is because the transformers were carefully chosen to optimally match the electrical and sonic characteristics of the DL-103 [crucial when choosing traffos to amplify the output of any MC cartridge], and so both items work synergistically as a PAIRING, not as separate entities, as often is the case with other MC cartridge/SUT combos when both are from different manufacturers.

Therefore, the former creates a 'musical rightness', which is exactly what you're hearing and why I wanted to revisit the AU-310 - and it's been fruitful!

And yes, it would be relatively easy for anyone competent with a soldering iron, and a little knowledge, to bypass the switch. It probably won't make a lot of difference, sonically (as it's been well-designed and executed, in the classic Japanese tradition), but worth doing, simply because we're purists

Therefore, I'll have that done to mine in due course, as well as fitting better phono plugs to the output cables, as things have defo moved on in that area since the 70s! That done, however, I'll leave it as it is, without altering any cables, as those are fine as they are.

So are you going to tackle the job yourself and see what improvements, if any, you get?

Marco.

[Marco]

Some suggest Quad amplifiers have a 'family sound'. They don't. The 303, 405, 306 and 606 each have rather different ways of presenting music. The 606, 707, 909 and QSP etc., sound very similar to each other though. I wouldn't mind an early 909 (in black of course ) actually, it's a big softy with a laid back benign character, powerful though, but not as involving as the 306.

Interesting, mate. The "big softy* thing wouldn't interest me though, as I'm not into that type of presentation. That's one of the reasons I opted for the 306, as it's known to be a punchy and dynamic performer. I don't do 'pipe & slippers'.

I suspect Quad amps may have all had a 'family sound' had PW still been around and responsible for the design and 'voicing' of the company's products, but I reckon that the varying sonic signatures/musical presentations of the different amps in the Quad range simply reflect the 'goals' of the company at the time, and the direction that was being taken by those who were in charge.

Marco.

[struth]

Quad I had(the vena2) was a nice amp and dac. good sound from it and not bad value

[The Black Adder]

Yes it was a pair modded 405-2s. He's gone back to his roots now, however, with a full Naim system and Isobariks!



Yup, exactly, just a different 'take' on the music. It's the classic trade-off between transformers and transistors!

However, the reason that the AU-310 works so well is because the transformers were carefully chosen to optimally match the electrical and sonic characteristics of the DL-103 [crucial when choosing traffos to amplify the output of any MC cartridge], and so both items work synergistically as a PAIRING, not as separate entities, as often is the case with other MC cartridge/SUT combos when both are from different manufacturers.

Therefore, the former creates a 'musical rightness', which is exactly what you're hearing and why I wanted to revisit the AU-310 - and it's been fruitful!

And yes, it would be relatively easy for anyone competent with a soldering iron, and a little knowledge, to bypass the switch. It probably won't make a lot of difference, sonically (as it's been well-designed and executed, in the classic Japanese tradition), but worth doing, simply because we're purists

Therefore, I'll have that done to mine in due course, as well as fitting better phono plugs to the output cables, as things have defo moved on in that area since the 70s! That done, however, I'll leave it as it is, without altering any cables, as those are fine as they are.

So are you going to tackle the job yourself and see what improvements, if any, you get?

Marco.

Cool... To be honest I think someone with the knowhow would be best to do it. Maybe Alan (Firebottle)?

I'm just enjoying it as it is at the moment, it has a stonking sound.

Yeah, maybe the switch won't make a jot of difference but I don't think I'd ever need to use the bypass, so it might has well be disconnected. lol

[Firebottle]

I had the AU-320 SUT with two ratios, another excellent performer. On close inspection I came to the conclusion that the switches were of excellent quality with no need to remove or replace.

With dexterity the switch in the 310 could be dismantled and the all the contacts cleaned, but it is fiddly.
I could wire it out of circuit if chosen to Josie.