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First One - mosFET amplifier module

Hi vpi and all :wave2:

It goes like this in order of SQ:
- VSSA v1.4
- First One v1.1
- First One v1.2
- First One v1.3

First One v1.3 certainly has the edge and so far reserved to orders of ready made premium quality First One amplifier only.

After official presentation in October and according to public's reaction we'll decide how to proceed.

In near future there will be a lot more new interesting amplifier's stuff and accessories offered to DIY community, stay tuned. ;)

L.C. :cheers:
 
Hi Theo :wave2:

Well in terms of SQ is a strong step forward, in terms of a hardware it is two hour modification job for an experienced DIY-er.

If there will be good reviews than I would probably publish step by step instructions how to turn v1.2 into v1.3, it would worth the effort, but please wait for some next review.

Maybe Mikka had just experienced a wow factor and now the things are not so good as seemed at the beginning. :rolleyes:

Let's wait and see. :cheers:
 
R&D never stops...This is great!

Now I know why we are only three stars rated thread. :D

If I look around there's a lot of products having a lot higher versions numbers than the First One. SMPS1200A400 is version 7, nothing wrong with that. :yes:

Hi Lazy Cat,

I support 100% your on-going R&D...
All great minds continue to advance the state of the art in their areas of expertise....I look forward to 20 more years of your innovation and standard setting designs...Keep up the good work!

It does not matter when one chooses to buy into your designs, we can all be assured of on-going support and upgrades...
Only someone who has spent too long "banging his head against a wall" will fail to see this...


Cheers
Derek.
 
Thought I go look here.

I am self a hybrid man, have a working one with tubes who drive mosfets in dc mode, no gate capacitors of 1 uF to separate dc from mosfets, this is what I see much.

Your design looks good, I have not yet design it with smt components, I am older and eyes you now, and I like the old resistor build look, very strong and better because of high voltages.

Here is a very nice smps for your needs, give big voltages switchable.

and my board of a loudspeaker measurement jigg, amps is not yet ready.

regards

kees
 

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As we don't want to have more than 45 C in idle, please use heatsink having thermal coeficient of 0,5K/W or less for each channel.

First One module has 35 W idle power dissipation when supplied from +/-63 V PSU.

Andrej,

Does this mean that the amp heatsink should not exceed 50 C when playing music? My heatsink temp on my FO amp goes up to 52 C after an hour of listening. So I probably need to get a bigger heatsink.

Based on your documentation, between 40 - 60 C is still okay. Correct me if I'm wrong.

Fred