DIY: Pass F5 turbo v2 initiated

[omishra]

Hi Om,

Is there any way to make amp insulator free??? Asking so as Insulators add to thermal resistance and therefore degrade heat transfer and also breakdown can occur causing the amp to fail.

Being Class - A, direct metal to metal contact can facilitate much better heat transfer.

What say?

There are many thoughts.

• Drains of MOSFETs are connected to back metal case of MOSFET. Otherwise it would be short circuited with grounded chassis. So which should not be connected to heatsink anyway.
• For insulator free contact anodised heatsink anyway insulates from electricity. But it could be breached easily.
• Here in this circuit all MOSFET drains are connected to output and from output we take feedback. If somehow we remove insulator from MOSFET and isolate heatsink itself from grounded chassis and remove insulator then still live heatsink is not a good idea. Though this would work.

So that small sacrifice is okay, adds 10 degrees more to case of MOSFET. Still we are safe zone.

Om,

Did you get another stereo set?

Thanks

Yes I got it. I will work soon when gets some time. Now office workload is too much.

 

[magma]

Hi

Dear all

does anyone have a spare F5 turbo V2 kit ?

i may plan on building one when i build a clients cabinet

please Pm

P.S : cmsajith : please clear your PM box
i cant ping you

let me know
All the parts you have and can offer me
Parts that i need to source ( that you dont have)

rgds
ALi

 

[captrajesh]

NOTE: captrajesh has better heatsink which is single piece strip. That way all MUR diodes could be kept one side of PCB on one heatsink with using proper electrical isolation pads. Also if space permits then all MUR diodes could be attached to bottom plate with using proper electrical isolation pads.

Though I saw this post, I somehow missed this bit. Just saw the link in this post of Omishra.


Are you talking about the heatsink for the MUR diodes or the the heatsink for the main MOSFETS?

I did buy a long heatsink for the MUR diodes but am not of the layout. My main heat sinks are not single piece but two heat sinks similar to that of N56 of Perfect Metals joined by milling a rectangular strip and smeared with 'Arctic Silver' compound before shoving it in for better thermal coupling. This has literally made them into a single strip and adds to the structural stability because they form part of the cabinet structure; similar to monocoque design of a car sans any chassis.

Pics are given below:

 

[omishra]

Hi captain, I was talking about rectifier diodes mouthing not amp board. Regards

 

[jenson]

Im now, the proud owner of Om's build of Pass F5 turbo v2 !! cant be happier.

it's paired with my newly acquired JBL4312E.

Pat Metheny's Still life played like nobody's business. instrument separation were ninja precision and played with such command and delicacy that my jaws dropped. i never heard this song like this before. total revelation.

and im still not using it in a optimized way as i do not have a pre-amplifier, my cd player as everyones knows is a blue ray player and what not

coming to pre-amp - what to say, this DIY community is just too good ! im not sure whether i should announce this but im procuring the DCB1 pre-amp from our FM Raghu who very graciously is helping my set it up in a beautiful case with separate power supply. the same pre-amp would also house the CNC Phono stage which was built for me Sachin! (Sachin, finally, ho gaya yaar !

i cant wait to see how this setup would sound!

setup would finally have CNC Phono + DCB1 + Pass F5 turbo v2 -> JBL4312E

plan to add entry level dac by Schiit to make best use of wav/flac's...

Once again - Thanks to Om for sparing his masterpiece.
Thanks to Sachin for populating the CNC board for me!
and Super thanks to Raghu for building DCB1, completing my CNC build, creating a separate PS and housing them a Case as finished product...what else could i ask for !!


btw -for guys looking for serious Amp under 50k Range (but sounding 10 times its cost) - you should give this one a serious consideration. im in pune for ow, will be relocating to Ahmedabad by end of this month. i welcome guys to audition this masterpiece.

 

[kuks1]

Hi Jenson,
Congratulations on the F5. I have heard it at Om's place, i must say that his whole set up is/ was wonderful. Very natural/neutral sounding, pleasing to the ear. I had planned to be there for 45 minutes but ended up spending over 2 hours listening to all kinds of music from hindustani classical to old marathi hits from pop to Hard rock. Congratulations once again on the new acquisition. Hope you have y-ears of enjoyment with your new set up.

Mishraji,
So whats in place of the F5 v2? What happened to le monstre? would love to hear that too.

regards

 

[sachu888]

Monstre is coming

Regards
Sachin

 

[kuks1]

Monstre is coming

Regards
Sachin

Looking forward to that.

 

[omishra]

Looking forward to that.

Actually it is difficult to beat Pass F5 turbo amp. That resolution and control is faraway from any class AB amplifier. It took me 3 months to take decision. Finally Raghu agreed to help me in building another then I let this go.

I have 2 more unbuilt kits with me. So I am surely building same again. But I also need small power amp for listening in night when I could forget switching off at night. So there will be F5 turbo for winter and Jean Hiraga for summer.

 

[magma]

a correctly implemented pass design is a difficult thing to beat
(I say correctly implemented - since nelson generally only shows you the ckt but doesn't really fully divulge the best way to implement it - those secrets he keeps for himself for his commercial creations - understandable )

for e.g a 30.1 is born from the first watt series
however it cascades the fets and uses 12 pair of devices as opposed to 2 so as to get longevity with lower bias


my personal pass is also being upgraded since i couldnt see anythng better

will have 8 devices ( opposed to 4 - so obviously a new layout and board ) , a larger cap bank , a higher voltage output ( which is required for my new speakers .,so change in trafo )
all caddocks ( which will burn a hole in my pocket) and new parts for the amp boards


hoping it will be worth the effort

 

[kuks1]

Actually it is difficult to beat Pass F5 turbo amp. That resolution and control is faraway from any class AB amplifier. It took me 3 months to take decision. Finally Raghu agreed to help me in building another then I let this go.

I have 2 more unbuilt kits with me. So I am surely building same again. But I also need small power amp for listening in night when I could forget switching off at night. So there will be F5 turbo for winter and Jean Hiraga for summer.

Haha...Winter is fast approaching, so i guess you have time to build le monstre...any ways all the best for the new build. I know "ki perfection ko improve karna mushkil hota hai" but you guys i am sure would find ways to even do that

 

[SanjeevM]

Friends,

After the experience gained over time, which would you say is the best sounding DIY Amp (Class-A) in the range of 30 to 50 watts today?

 

[magma]

the one you build will be the best sounding!!!

no DIY guy is gonna say otherwise is he ?

 

[saikatbiswas82]

the one you build will be the best sounding!!!

no DIY guy is gonna say otherwise is he ?

+1. Very well said.

Friends,

After the experience gained over time, which would you say is the best sounding DIY Amp (Class-A) in the range of 30 to 50 watts today?

Few options to look at:

1. Pass F5
2. Pass F5T
3. Pass F6
4. Pass VFET
5. Pass Aleph J
6. Hiraga
7. JLH 30W

All are legendary. Pick any. I believe these 25-30 WPC will be more than enough to drive any speakers.

 

[jls001]

Not always true

 

[sadik]

If i get a Proper Layout files in PDF format i can try my hands on F5. Recently i have built Jean Hiraga Super Class A 30 Watts Amp. The Sound of this amp is superb, very clean and clear on Mids and Highs. This is the Only Class A Amp i have built and heard.

 

[sunilmani]

Same here. Have not build a class A amplifier before. Would be interested in building one.

 

[captrajesh]

Nice to hear that you have taken up the F5 project. I'm looking forward to you taking this to the build stage. I've subscribed to this thread.

Updating the thread after a long while. Due to lack of time, I've passed on the kit to a FM w?h?o? ?t?h?o?u?g?h? an electronics guy, ?i?s? ?a?t?t?e?m?p?t?i?n?g? ?D?I?Y? ?f?o?r? ?t?h?e? ?f?i?r?s?t? ?t?i?m?e?. Best of luck to him.

 

[jmascreen]

These beauties are back in Pune, Thanks Jenson for hand delivering it from Ahmedabad to Pune. Really appreciated your efforts, communication and commitment during very tight schedule.

Im now, the proud owner of Om's build of Pass F5 turbo v2 !! cant be happier.

it's paired with my newly acquired JBL4312E.

Pat Metheny's Still life played like nobody's business. instrument separation were ninja precision and played with such command and delicacy that my jaws dropped. i never heard this song like this before. total revelation.

and im still not using it in a optimized way as i do not have a pre-amplifier, my cd player as everyones knows is a blue ray player and what not

coming to pre-amp - what to say, this DIY community is just too good ! im not sure whether i should announce this but im procuring the DCB1 pre-amp from our FM Raghu who very graciously is helping my set it up in a beautiful case with separate power supply. the same pre-amp would also house the CNC Phono stage which was built for me Sachin! (Sachin, finally, ho gaya yaar !

i cant wait to see how this setup would sound!

setup would finally have CNC Phono + DCB1 + Pass F5 turbo v2 -> JBL4312E

plan to add entry level dac by Schiit to make best use of wav/flac's...

Once again - Thanks to Om for sparing his masterpiece.
Thanks to Sachin for populating the CNC board for me!
and Super thanks to Raghu for building DCB1, completing my CNC build, creating a separate PS and housing them a Case as finished product...what else could i ask for !!


btw -for guys looking for serious Amp under 50k Range (but sounding 10 times its cost) - you should give this one a serious consideration. im in pune for ow, will be relocating to Ahmedabad by end of this month. i welcome guys to audition this masterpiece.

 

[jmascreen]

Moved to a simple setup only with BDP and TT connected to DCB1 + F5T to my Diy 3Way and thoroughly enjoyed for last four days at temperature almost 42 deg with top floor flat and F5T running.