Gainclone with Fostex

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Dear People,

I'm planning to make my own sound system and I've just started with building a non inverting gainclone amp.
I'm living in Jakarta indonesia and in the shop where i bought the parts for my amp there was a pair of fostex FE206E playing with a tube amp and I was suprisingly impressed with the sound of it.

I've been reading some about the fostex speakers and I like it.

To start my choise would be the speaker on this site:

Its simple and the reviews sound good.

Now I wonder if this design (or any fostex design) would sound good with my gainclone amp.

Any reply is very welcome.

M.J. King designs sound excellent and are highly recommended.
I even think they sound better with Gain Clone than rear loaded horns sound with it. They are more forgiving. After all GC is still silicone amp. Rear loaded horns sound better with tubes.
I'm using Fostex driver in bass reflex enclosure (very similar design except BS instead of MLTL) with batteries powered Gain Clone and it sound great. Use the best components you can while building Gain Clone. I'm using Riken and Caddock resistors, BG N caps in power supply and Cardas wire for all connection. The sound of Gain Clone built with cheap parts is really much worst and Fostex drivers will show it right away.

I´m using a gainclone with my FE167E´s and like the sound very much.
Am very tempted to turn it into a current amp though which is simple enough; just do a search, you´ll find some schematics with LM3875 and the sort.
Alternatively you could wait for Firstwatt´s schematics of the F1 to be published. Should make a great amp which is almost as simple to build.

If you don't already have the drivers, I'd advise that you go with the FE207E if you can -it'll need less BSC than the FE206E.

I agree with your statement about the amount of BSC required being more for the FE-206E then the FE-207E. But why is that a disadvantage?

When I swap the higher Qts Lowthers (PM6C, PM6A, DX2) with the lower Qts Lowthers (PM2C, PM2A, DX4) the bigger stronger magnets with the lower Qts always sound better to me with more detail and dynamics. Yes I need to use more BSC and probably still don't get as much bass output, but the midrange and high end are definitely better and I prefer that compromise. These are subtle differences but clearly audible and repeatable.

I have not heard the FE-207E or FE-206E so I cannot comment if the same effect is present. But I would not make a decision based only on the Qts and the amount of BSC required for a given driver.
True Martin, in itself, there's no real disadvantage. My concern is not so much to do with the driver as the amp. I would tend to favour the FE207E and less BSC in this situation simply because it keeps the driver efficiency up as high as possible. Not strictly much of an issue with chip amps, or you'd hope not at any rate -but I have some reservations about a lot of these things. Those I've seen, heard and measured generally appear fine at low levels, but distortion appears quite quickly as level increases. I don't think this is so much a characteristic of chip-amps so much as the less-than-great implementations (4 so far) I have run into, so I'm not implying this is a universal problem, just something to be aware of. Hense my thinking that keeping the efficency as high as possible might be worth doing so the amp isn't stretched.

I suspect that my favouring the 207 is also down to my own listening preferences -I reckon I prefer a slightly warmer presentation as I find it more relaxing to listen to over long periods (I must be getting old or something!); I might give the 206 MLTL another try however, I have some still in their boxes somewhere. Will let you know how they compare to the 207 MLTLs I built a few months back.

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