Project for Semisouth R100A and 085

[316a]

I have a pair of each and was thinking that I should really put these rather expensive parts to use . What springs to mind is a Zen type amp with R100A underneath a R085 top load .

May I hear tour suggestions , please?



316a

 

[Zen Mod]

SJEP or SJDP ?

 

[316a]

The parts I have are

SJDP120R085
SJEP120R100A

316a

 

[dady]

Are they different between them?

 

[Nelson Pass]

Different enough. The DP is a depletion mode part which typically has
Vgs voltage at -3 to -5V, and the EP is enhancement mode at about +1 to
+2V.

After that, they are somewhat similar.

The DEF amps discussed elsewhere in this forum used the R085's for the
depletion mode device.

 

[Nelson Pass]

What springs to mind is a Zen type amp with R100A underneath a R085 top load .

Maybe R100 follower with R085 self biased current source,

or

R100 operated Common Source mode like in J2 with R085 on the top as
mu follower.

 

[Zen Mod]

with pair of SJEP , say Aleph Jango (Aleph J iteration , one of Most Greedy Boyz made by Papa's hints)

 

[Zen Mod]

with pair of SJDP , maybe DEF amp , even if that one is for more faint in heart , needing lesser amount of watts and more romance



you can always send them in OPLDF , for proper treatment

 

[316a]

R100 operated Common Source mode like in J2 with R085 on the top as
mu follower.

That's the sort of thing I was thinking of . For this project I intend to only purchase the heatsinks and output capacitors and really splurge out using some of the parts from 'the mountain' .

It will be built on a piece of wood and be a perpetual prototype so almost anything goes I have 97dB sensitive speakers (15"+TPL150H) so only need a clean watt .

The J2 thread is a beast . Is there a go-to post that has a schematic or can you share something ?

What about the Amp Camp Amp with Semisouth devices top and bottom ?

Thanks to all who responded

316a

 

[res07njc]

I was going to say use the R100 in an ACA, adjust for lower Vgs of the R100 as some have done previously with a 1 pair aleph mini (you can search DIYA, member "teabag" even made an article), except with ACA mu follower as irfp240.. and maybe use the 085 for something else.. (obviously that DEF amp).

 

[Zen Mod]

J2 is outa combination , needing pair of SJEP per channel

 

[dady]

Thanks Mr Pass, one question is possible to use a SJEP like amp device and a ordinary 240 as CCS in the aleph J? or must use both Jfet together ?

 

[Zen Mod]

read #7 again

 

[Zen Mod]

The Aleph Jango

one SJEP down and one IRFP150 or IRFP240 on top , enough in my book

 

[Zen Mod]

hate photobucket

here it is properly attached

 

[oreo382]

J2 is outa combination , needing pair of SJEP per channel

Would this one work? (Digikey)

Cree C3M0120090D
Silicon Carbide Power MOSFET
C3M
TM
MOSFET Technology
N-Channel Enhancement Mode

 

[Dennis Hui]

Hi ZM,

For a single SJEP and IRFP150, would you lower the source resistor to ~0.22R?

Thanks,
Dennis

 

[Zen Mod]

yup , all of them to same value

(general remark for number of big resistors - if one pair of outputs , then two parallel in output node....if two pairs of outputs , then four parallel ones in output node)

say 0R33 is safe bet , while 0R22 is for fearless Papa Followers

(seriously now - nothing to fear from)

 

[Zen Mod]

Would this one work? (Digikey)

Cree C3M0120090D
Silicon Carbide Power MOSFET
C3M
TM
MOSFET Technology
N-Channel Enhancement Mode

dunno - didn't tried and frankly - lost count of tried substitutions , here on forum

maybe because I wasn't personally interested in finding substitute for Semisouths

 

[dady]

Probably with the paralleling you improve the damping of this amp. 1A per transistor of bias? 24volts?