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Crescendo ampilifier elektor1982

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diyman

Member
Joined 2001
Crescendo

This is the circuit of the "baby" mini Crescendo rated around 50W. I have built both and IMHO the higher power power version sounds much better. The mini Crescendo sounds quite warm but mid range is slightly compressed and vocals do not sound very open. Maybe you can muck around with the feedback cap to tweak the sound a bit. Had some oscillation probelms with one channel and the problem sorted out using regular 5 pcs paralleled 1ohm 1W carbon resistors for the output stage instead of a 0.22ohm wirewound. Also used MJE340 and 350 instead of the BF469 and 470. Also sounded better, I think! Once up and running ran more than 10 yrs without any problem.

My 2 cts:) :)
 
Bensen

Bensen

Member
Joined 2003
I don't really know if this is the Gigant, but this is a Crescendo with 4 output devices, the original Elektor design uses differnent transistors.
 

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amplifierguru

amplifierguru

Disabled Account
Joined 2004
members.dodo.com.au/~gregball/guru_001.htm
Hi Benson,

Referring to your posted schema. It's such a pity that it's sooo
wasteful of supply. That's the price you pay for running MOSFETs as source followers. The gigant has conceded and run higher drive supplies to reclaim some of the output losses.


Now if only they were to operate them as CE then they could go R2R. And guess what - the slew rate would go up..up !

Why? Anyone?

Cheers,
Greg
 
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diyman

Member
Joined 2001
250W Crescendo

I built this as well! Mediocre sound but reaaaly good driving power. Never heard my my pair of Kef 105s sing so effortlessly. Fairly stable and ran for years without any problem but just like the other Crescendo members, midrange is slightly dark. Some female singers can sound as if they have a slight cold!! Playing around with the feedback capacitors can change the sound. Perhaps you can try different values or bypassing it with some PP caps. If you're looking for sound reinforcement, go for it!! Mine was built with all the recommended solid state devices without any bridging.

ckt :) :)
 
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