F5 with 2SK2013/2SJ313

[Zen Mod]

.....I'm a proud owner of a couple of Altec VOT ......

show us porn !

 

[GuidoR]

show us porn !

hehehe,
not the complete original however, the components are mounted in a sort of a dipole (inspired by this Alnico Saba Speakers Endorphine P21), soon I'll post some pics (if not censored )
Afterall, I'm a poor padanian man...

Guido

 

[massimo]

Afterall, I'm a poor padanian man...
Guido

Just for who may wonder "padanian? what's padanian?"
Padanian nationalism - Wikipedia, the free encyclopedia

But Guido and I are only joking (after ZM's Poor Serbian Man...), nothing to do with those gentlemen indeed.

 

[Zen Mod]

Italians are just little less wakoo than Serbs

 

[GuidoR]

show us porn !

Naked!

all is copied, nothing original.
Cabinet "à la Lampizator" Endorphine from Kingston Kitchen, filter modified (this http://digilander.libero.it/steveviso/audiogarage/viso485xov.html) from the original VOT.
Some exotic cap (Siemens, ERO, Wima) and no problems about efficiency

Sorry for the OT

But the original project (xed F5 with small Toshibas) is on its way, stay tuned!

Have a nice 2011!!!

Guido

 

[Tea-Bag]

Sweet

 

[jacco vermeulen]

Yep, judging by that design, you're Padanian.

 

[Zen Mod]

Fugly !

I don't like ya .

Put on same ignore list with Cal W.

 

[GuidoR]

Yep, judging by that design, you're Padanian.

 

[Valeriano]

Those babies looks good and sound very nice, trust me

forza Guido!

happy new 2011 to everybody guys!

ciao
Vale

 

[Samuel Jayaraj]

Waiting for the Toshiba parts to arrive from utsource. I ordered for 8 pairs; they charged me 2.00USD each, plus handling and shipping. I still need to get atleast 2 Nos. of 2SJ74BLs to get this going.

 

[anilva]

Waiting for the Toshiba parts to arrive from utsource. I ordered for 8 pairs; they charged me 2.00USD each, plus handling and shipping. I still need to get atleast 2 Nos. of 2SJ74BLs to get this going.

Hi,

What are you building? F5 with 2SK2013/2SJ313 with 4 pairs per channel?

Cheers.

 

[Samuel Jayaraj]

Yes but the variant of Nelson's F5, presented by Juma in the first post of this thread. I want a high resolution amp with a bit of midrange warmth to match the Fostex 168SigmaES.

Any chance of getting 2SJ74BLs?

 

[anilva]

Yes but the variant of Nelson's F5, presented by Juma in the first post of this thread. I want a high resolution amp with a bit of midrange warmth to match the Fostex 168SigmaES.

Any chance of getting 2SJ74BLs?

Sent a PM.

 

[Samuel Jayaraj]

Thanks but I don't see any PM. Is it due to server latency or .......?

 

[Iloveswan]

While waiting for the little Toshibas to come from Zhoufang (10 weeks lead time ), I’ve been attracted (and who has not?) from this http://www.diyaudio.com/forums/pass-labs/172770-balanced-f5-question.html thread, so I thought to a 313/2013-based version. The attached schematic comes directly from that thread, and the values of R1/R101 and R2/R102 (widely commented) so as R7/R8 and R9/R10 are copied from EUVL’s schematic (see attached), so consider them as tentative values.
Is this beast feasible? Are there alternative values of supply voltage / idle current that could be considered in order to achieve the “sweet spot” or even lower the overall dissipation (at the price of a lower max power output)?
I’m aware of dissipation issues, so we (in fact, I’m representing a bunch of ardent DIYers) are already thinking to a very ambitious (for us) case, but this is another story (another case, in fact ).

Juma (or any other), could you comment please?

Guido (poor Padanian Man)

wondering if different source resistor for SK170/J74 is needed or not... especially with the feedback situation...

 

[Zen Mod]

take that from this point of view - they can't hurt

 

[Samuel Jayaraj]

Finally, my Mosfets have arrived from Utsource. Now begins the hunt for 2sj74s. In the meantime, I might even try 2N5461 for the P-channel JFET and try out the amp.

Just two questions, should the 4K7 NTCs be disc type or screw-type and if discs, should they be in contact with the heatsink?

Will a bias of 1.6Amps be O.K. for 4 pairs of Output devices at rail voltage of + -20 Volts?

I have 18-0-18 volt 160VA torroids that I am planning to use with Juma's published Cap multipliers. Thanks.

 

[juma]

... should the 4K7 NTCs be disc type or screw-type and if discs, should they be in contact with the heatsink?

Disc type, leaning on the heatsink, but not too tight.

Will a bias of 1.6Amps be O.K. for 4 pairs of Output devices at rail voltage of + -20 Volts?

Yes, it's still 400mA per MOSFET

I have 18-0-18 volt 160VA torroids ...

I would use 2 of these - one per channel.

 

[Zen Mod]

for 74 - ask Zhoufang or Spencer

NTC- disc shaped are OK - Papa use them , just leaned on mosfet case
you can glue side of it with RTV Silicone

biasshmias - ask Juma ; he certainly tried ad decided

safe bet - use what's prescribed (in first posts) for dissipation per device