Tube/MOSFET hybrid results/comments/suggestions?

[lgo51]

OK, i've been reading a lot and searched for *any* posts on hybrid amp actual results w/o much luck.

I've been looking at the Hybrid and Hybrid+ amps by Generoso Cozza described here in some detail. Sure does look enticing.

What i'd like to know is if anyone has experience, heck even hearsay would be nice, with this or any of the handful of other hybrid circuits floating about? My particular goal is to build a relatively low power amp for the top end of a tri-amp'd setup. [Yes, Nelson, i'm watch'n for your cross-over with great anticipation ]. Did i mention that the middle tier is covered by an Aleph3 - from the master his good self.

Thanks all!

[SemperFi]

I've been using a hybrid for some years, and am very pleased. I build a few different amps a year, and always end up using this amp no matter how good I feel the other designs are. It simply sounds great. It's single-ended so rather low powered, but certainly powerfull enuff for me.
It's found here

http://home.c2i.net/semfielec/tubemos.htm

I've now built this amp into a single chassis, so it's neater looking and less cablings and boxes.

If you need more power, a PP output stage is more practical, and just as well done as a hybrid vs purebrid.

Personally I dont like the design you refer to since it has loop NFB.

Regards, Nick.

[ezmeralda11]

http://www.uspto.gov/ and search patent #5,017,884

It'll also reference numerous past of-the-art designs you can view too. The company using that patent in production today is www.avahifi.com. There current amplifier models incorporating it are not low powered, quite the opposite, 160wpc to 250wpc. However, they seem to be very nice hybrids and better than most. Work what you can with the circuit. I own 'em.

[lgo51]

Originally posted by ezmeralda11
http://www.uspto.gov/ and search patent #5,017,884

It'll also reference numerous past of-the-art designs you can view too. The company using that patent in production today is www.avahifi.com. <snip> Work what you can with the circuit. I own 'em.

Thanks for that great reference. Very interesting reading. As they say; 'the devil's in the details' so it would be very instructive to study some of the realized designs.

LarryO

[lgo51]

Originally posted by SemperFi

I've been using a hybrid for some years, and am very pleased. snip It's found here

http://home.c2i.net/semfielec/tubemos.htm

I've now built this amp into a single chassis, so it's neater looking and less cablings and boxes.

Hi Nick,
Interesting read. Would you have any pix/prints of yours that you'd like to share? Did you build it up as a balanced design?

Personally I dont like the design you refer to since it has loop NFB.

Hhmmm, that seems to be on the those 'political' topics. Liberal = 0dB NFB, Conservative = 18dB NFB, Moderate = 6dB NFB.

LarryO

[Nelson Pass]

100 dB would be radical conservative (Iverson)

50 dB would be reactionary conservative (D'Agostino)

20 dB would be center of the road moderate (Rowland)

10 dB would be moderate liberal (Curl)

0 dB is foaming-at-the-mouth, (rrrrrrrr!! Mad Dog!! rrrrrr!!)

[SteveG]

Well now, this is strange! I find myself agreeing with the liberal viewpoint for the first time in my life!

[HarryHaller]

Does it strike anyone as remarkable that Mr. Pass knows that much about how much feedback his comtemperaries use. Having poked around with a few designs from the list of usual suspects, I actually concur that he is accurate on these facts. I am casting my vote for "Amplifier Nerd of the Millenium" for Nelson Pass.

H.H.

[lgo51]

Originally posted by Nelson Pass

100 dB would be radical conservative (Iverson)
50 dB would be reactionary conservative (D'Agostino)
20 dB would be center of the road moderate (Rowland)
10 dB would be moderate liberal (Curl)
0 dB is foaming-at-the-mouth, (rrrrrrrr!! Mad Dog!! rrrrrr!!)

Hhhmmmm, i don't see a PASS in this scale

[lgo51]

All kidding aside, since Generoso Cozza has referenced your Zen design, Nelson, would you care to comment on his hybrid offering?