Gainclone heaven ?

[manisandher]

Hey Paul, it looks like it's high time for my promised visit to your place. I'm really interested to hear how your gainclone compares to my Berning 300B. Let's liaise via PM and get the visit organised.

On a slightly different but still related note, does anyone know of a gainclone amp that can output ~100W into 8 ohms, which is happy driving a 2 ohm (and even 1 ohm) capacitive load? I've already tried a class-D amp (Hypex HG700) with my Quads and would now like to try a gainclone, having heard so many good comments about them.

Mani.

[PeterSt]

Hi Mani,

Do notice that I never sorted out about the load the Gainclones can bear, but getting out 100W of them should be easy. It's similar what I do (also in this topic), which is putting them in series. Also, the other day I measured it all, and saw no degradation (with a pot in between to level out the whole contruction; see earlier in the topic).

Btw, my speakers go well under 2 Ohm, but don't ask me whether that's 1 Ohm or 0.1 Ohm.

Regards,
Peter

[Nick]

Paul hi,

I am so pleased that you are having such a good experience with the Gainclones. I really must do something with my SETs I really don’t think I will be issuing them again, I guess your probably thinking  the same way  . My SETs are packed full of goodies like VCaps (loads) tantalium resistors Black Gates everywhere, mesh plate 300B’s and silver. I could have built my gainclones for a fraction of budget for the upgrade parts alone. The strange thing is I am very satisfied with the sound and for the first time in absolutely years I have no immediate plans to change my amp. What a bargain these things are 

Your findings with the speaker wires is very interesting. I have always viewed insulation as a necessary evil,  I’m sure the type of dielectric has a massive effect on sound. Your trails with 6 metre runs must really highlight the effect. I also have long runs so you have me thinking now, maybe this could be a project for when the nights draw in.

The next step you have planned to bi-amping was a real real eye opener in my system, a major step, I really hope you have a similar experience. Be sure to let us know how it goes.
 
Mani,

I went down the 2 gainclones per channel route to keep options open to build two balanced input, bridged amps one for each channel. The data sheets show, when bridged Gainclones are able to drive high power outputs and tricky loads.  Looking at the electronics you are considering though (serious stuff  ) I would be surprised  if Gainclones could complete, but then again they do seem to be capable of pulling out a few tricks.....

Best Regards,

Nick.

[juanpmar]

Talking again about speakers cables I´d like to know your opinion on this kind of Remote Sense cables, used mostly, but not only, with the Spectron class D amps. Have you ever hear about it  and the way this speaker cables are integrated as a system with the amps in order to minimize the distortion and noise?.

http://www.spectronaudio.com/remotesense.htm

and here for the most technically prepared among you:

http://www.tubecad.com/2010/03/blog0184.htm

As always I´m more interested in the audio part than in the scientific part of the issue, but just in case I give you all the information I could got about it.
Juan

[PeterSt]

I would be surprised  if Gainclones could complete

You mean before they explode, right ?

[BertD]

Btw, my speakers go well under 2 Ohm, but don't ask me whether that's 1 Ohm or 0.1 Ohm.

Are these the same speakers I have? If these go that low in impedance then there must be something wrong with your set-up...

Bert

[PeterSt]

Well, I didn't want to ask you directly, but since you are responding anyway ...

The speakers you provided (of course ). So, how low do they go ? I recall 2 Ohms for sure ... or ?

Thanks,
Peter

PS: And for others : it is Bert who provided my Gainclones just the same. And that means of line filtering, and ...
But I'm not so sure Bert likes to receive 25 emails about this ...

[PeterSt]

And Bert ... knowing you a little ...

To me it occurs that having such a low resistance (at frequencies) must be a negative. Well, I don't know anything about this. Maybe you like to explain a little about this ?

And maybe also how the (your) Gainclones respond to that ?

Thanks !
Peter

[Scroobius]

Hi Mani,

As mentioned above you could bridge a pair of Gainclones to get 80-100W also bridged pairs can be run in balanced mode if you wanted to. The GainClone chips are just about indestructible so you could test it with your Quad's without worry.

Come to think of it I am looking at my half finished bi amp GainClones why don't I bring them up on my next visit to yours and we could try them in bridged mode.

All the best

Paul

[BertD]

To me it occurs that having such a low resistance (at frequencies) must be a negative. Well, I don't know anything about this. Maybe you like to explain a little about this ?

Your speakers should not be lower than 6 ohms over their entire frequency range (impedance curve) giving the amplifier an easy load. Mani's ESL's are basically capacitors giving lower impedance at rising frequency which is a problem for most amplifiers, especially if you like to crank it up a little. Your gainclone is not sensitive to very low impedances in terms of distortion and even capacitance does not bring it off track, they just do not like low impedances limiting their maximum output.

Good thing is that the amps will not gradually start to "complain", they only make a weird (loud!) noise when the limit is reached (as if things are broken!). No problem for the amp or speakers though, it is an internal protection that just makes noise like that. If you do not hear that specific noise then all is well and you have plenty of power...

At your place you will not be able to hear the limiting noise coming from the GC's (and if you try then I do not want to be there without earplugs!!!) unless you connect low sensitive speakers to the amps and turn up the volume.

Bridging the amp gives it more headroom (+6dB), not sure if a bridged combo can be bridged as such again though but if so then a GC with enough power to drive an ESL could be created.

That's all I can tell about your GC's, I do not know about other chips (not even sure which chip mine uses!).

Bert

[PeterSt]

Hey Bert, thanks.

Bridging the amp gives it more headroom (+6dB)

I'm not sure this is correct. Of course it seems like thinking "twice as much", and although this by itself would be true in Wattage or something, this is not about 6dB. It merely will be about the 21dB or something - which is the gain.
Or ?

not sure if a bridged combo can be bridged as such again though

Well, this logically follows from my setup of course, but it really is not what I intended to propose. Maybe it works, but it won't be the best I think. So :

Just a normal mono GC for one channel, and behind that another one. Nothing about filtering.
This per channel.

Of course a next step could be about the filtering, but first one must need that.
Similarly it could be about a balanced setup; If you do it all together I'm not sure with how many GC's you will end up with. Haha.

not even sure which chip mine uses!

I think I know, but for me it is not important. What is, is that at least I am able to let the output show the same harmonics as the DAC throws out, or IOW it adds nothing to it (except for a small 3rd harmonic - I think I talked about this realier).
Anyway, this looks quite different from any other pictures I see from other amps. I don't care much about "but this is way down the audible level" ... I just don't want to see anything ... (which appears to be possible with the GCs to my own surprise).

I don't know much about the chips as I never dove into them really, but what Paul said is true : they are highly "instructable" (many resistor and cap options). But as far as I know in mine (Bert's) nothing is there on that department. It's really nothing else than the chip and gain resistor. And some filtering caps in the power lines, but that needs to be there.

Peter

[manisandher]

Mani's ESL's are basically capacitors giving lower impedance at rising frequency which is a problem for most amplifiers, especially if you like to crank it up a little. Your gainclone is not sensitive to very low impedances in terms of distortion and even capacitance does not bring it off track, they just do not like low impedances limiting their maximum output.

Bridging the amp gives it more headroom (+6dB), not sure if a bridged combo can be bridged as such again though but if so then a GC with enough power to drive an ESL could be created.

Thanks Bert. Much appreciated.

I've sent an email to Peter Daniels of Audio Sector, asking if he can make something suitable up for me. Meanwhile, does anyone know of a gainclone expert in Europe who might be able to help me?

Mani.

[BertD]

Meanwhile, does anyone know of a gainclone expert in Europe who might be able to help me?

If Gain Clone's can be bridged multiple times then I can help (using BD30 amp boards). I stll have enough BG's N types laying around to stick into a few boards... 

Not sure how much bridging you'll need though... (this totally depends on the size of the room and how loud you want to go).

Bert

[BertD]

Just a normal mono GC for one channel, and behind that another one. Nothing about filtering.

This way it is still the last amp in the chain being able to deliver the rated power for one amp where everything in front should be seen as source with more or less added gain...

A bridged amp is connected differently, more in "parallel" or "balanced" to be able to process more current or Voltage at the speaker terminal connectors.

Bert

[Nick]

Meanwhile, does anyone know of a gainclone expert in Europe who might be able to help me?

Mani,

The basic amp is very straight forward only a few design decisions to make like rail voltages and cap types if you start with a good design like Peter Danials kit. Help would be good to taylor the application to Quads but if Paul can configure his setup in bridged mode I would really start with a listen there. My guess is you will know really fast if it is worth going further. Now that would really be something if they do drive Quads well. I loved my old ESL63s but as I mentioned before affording amps that could drive them well was a problem at the time.

Back when I was using the SETs and thinking what next for a while whilst I was moving house I was using a Logitec 5.1 computer audio setup for amplification. The thing was it sounded brilliant driven by XX and a decent SPDIF interface. So 15ks worth of "proper kit" struggling to beat 220 pounds of 5.1 system (WTF !). Anyway I had started to read up about gain clones at about this time and decided to take a peak inside the logitechs. There was a row of 5 gainclones and another chip amp for the sub. I wired in my Duo speakers to the logitech amps and the sound was great.

As I say try to get Paul's amp into your system, or mine if you want to try unbridged. I am sure you'll know in moments if there is potential.

Nick.

Ps this could restart my interested in Quads again there's something I really miss about ESLs.