About possible Babelfish J interest

[couguarek]

SJEP's are hard to find now how about this ? Silicon Carbide (SiC) Super Junction FETs - GeneSiC Semiconductor - Silicon Carbide (SiCFET) | Online Catalog | DigiKey Electronics
Looks little strange, this is bjt or fet ??

Edit: I saw Nelson note about Genesic, so I know everything now.

 

[Zen Mod]

too expensive , if you ask me

there is a group of cheaper ones , but suspiciously low current capability , for our purposes - at least from quick glance on datasheets

anyway - I believe there is a thread about possible candidates of SIC parts for general Papamps usage

 

[couguarek]

I found smth, C2M1000170D
I read about they need only higher gate resistor then IRFP240, but what with LTP ? It will be enough current to drive one pair C2M per channel (mini version) ?

 

[Zen Mod]

It'll drive it , but I don't like Rdson value -1R

that's 5 times of IRFP240 and almost 20 times of IRFP150

 

[Zen Mod]

just one of threads http://www.diyaudio.com/forums/pass-labs/222098-semisouth-goes-dodo-what-now.html

if I find another one , will post

 

[couguarek]

http://www.diyaudio.com/forums/pass-labs/254622-new-sic-jfets-35.html

 

[Zen Mod]

yup, that one too

just to remind you - look for enhanced mode devices

 

[xrk971]

I just received my Babelfish J PCBs. They look really nice. Thanks ZenMod. And thank you to my benefactor who donated me the boards and transistor kit.

I have a couple questions (probably answered somewhere in this long thread).

Can I use IRFP240 instead of 150?

Are these heatsinks big enough?

 

[Zen Mod]

yes, you can use 240 , keep them in 35W/device heat base

I can't really judge fins height from angled picture , but I would use 2 of these per channel ..... counting on final dissipation in 70W bracket

sorry , we can't go against physics ........ even if we can cheat sometimes with Babysitter

 

[xrk971]

Or cheat with a small fan.

These are the 7.28in wide x 1in tall fins and 0.3in base thickness.

http://www.heatsinkusa.com/7-280-wide-extruded-aluminum-heatsink/

The manufacturer says 1.3 deg C/W/3inches.

I have 5in length so I think that says 55deg C for 70w. Then add 20C ambient for 75C so yes too hot.

 

[Zen Mod]

2 per side , and Babysitter in Summer

edit: save them for ACA or something like that , buy 4 new ones , at least 7" long

in greater scheme , that's petty money

 

[mpmarino]

Even half way around the world, and a decade later - I still find pieces of ZM in every corner of the shop.

 

[Zen Mod]

 

[xrk971]

I'm getting ready to populate my boards. Is this the best guide at present?

 

[Zen Mod]

yes

I believe I wrote somewhere - ZD can be either 5V1 or 5V6

anything from 300mW will do

 

[samoloko]

Zen Mod
I am Interested at your Babelfish J
would you please clarify for me
1) choice of j271 Instead off j74
2) Is there a sweet pot - recommended value of rails and bias and output pairs for optimum quality
3) Is this amplifier happy with 6 Ohm and a bit less efficient speakers
4) what Is gain with single ended source and If we have at Input balanced source Instead off single ended what will be gain
5) did you compare with Aleph J

 

[Zen Mod]

1.decent substitution for Toshiba JFets in this application and I have still plenty of them
2.if you read rest of the thread (under 200 posts , that's short ) , you'll find tutorials how to arrange for rails and output pairs, to fulfill your needs; it will keep same character of sound in pretty entire possible span of rails voltage
3.yup; see here : dynaudio | Search Results | Zen Mod Blog
4. 20db in both cases
5.it is Aleph J , Babelfished ; as with all of my Babelfish amps , it's probably even better than Papa's origins ...... if nothing else , it's having more parts

 

[xrk971]

Is the DIYA Store Dissipante 4U x 300mm depth a sufficiently sized heatsink for this amp?

https://diyaudiostore.com/collections/chassis/products/dissipante-4u

 

[Zen Mod]

pretty much yes, if you keep it in dissipation range of original Papa's Aleph J ........ which is aroundish 70W per channel

and , you can make Babysitter for summer days

 

[xrk971]

Yep, 70w per side was my target. I will order it then - not a bad deal at all with free shipping.