Hi Andrej,
A package arrived with two nice red boxes in it.
The build can start 🙂
Thanks for this project !
Regards,
Danny
A package arrived with two nice red boxes in it.
The build can start 🙂
Thanks for this project !
Regards,
Danny
Went to the post office today and now holding my First One modules in my hand right now.Realy top notch quality
Hi Andrej,
Your boxes arrived today.
The nice packaging gave me the feeling I got some big power triodes.
No schematic inside but I understand the reason.
Francis
Your boxes arrived today.
The nice packaging gave me the feeling I got some big power triodes.
No schematic inside but I understand the reason.
Francis
Great pictures LC, lot of fuel and horsepower in middle of box to get speaker coils on job.........
........
This much of power has a lot of juice, so far all the coils says
Of course there's still some room for an improvement, better caps are preferred always. Mundorfs on First One modules are there for a reason - to compensate such anomalies in a great portion.
Yes, one single reference GND/Earth chassis point is mandatory. No direct GND connection from First One PCB to the heatsink is present, no GND loops possible. Still First One has a clever solution implemented so it is completely safe to experiment with powered First One bolted to the heatsink and still outside the chassis. It won't oscillate or be unstable in any way.
Please read my next post about SMPS and grounding.
SMPS recommendation - final
Hi GB members
Little bit late on presenting the answer to the people invested in the First One, but with a good reason not to hurry too much on such crucial and important information about powering the amplifier.
Well, one single planned listening session unintentionally extended and prolonged from the weekend way till today as we got some firm conclusions, unanimous consensus among all present.
Two First One amplifiers, one with single SMPS1200A400, the other with dual SMPS1200A400, present. The source was Naim SuperUniti, speakers Thiel CS2.4, cabling multi UTP twisted pairs.
As usual both amps were preheated, each runing on music programme for a good hour before we compared them on five test tracks, volume leveled for each track on both sessions.
The result is not so far from our expectations, tight similarity with very slight differences noticable on momentary A-B test, otherwise, on not so closely conducted comparisons, it would be very hard or even impossible to recognize among them.
In which cases to choose single or double SMPS solution greatly depends on speaker's efficiency and impedance, these two parameters dictating how power hungry your speakers are and of course how loud you want them to be.
The ultimate and preferred First One solution is still dual mono configuration, although single SMPS completely fulfills the needs in a smaller system.
Great care has to be paid to properly conducted wiring, especially grounding as proposed in the manual. Slightly changed and optimized in chassis GND sch will be published together with DC sense circuit here soon.
Regards L.C.
Hi GB members
Little bit late on presenting the answer to the people invested in the First One, but with a good reason not to hurry too much on such crucial and important information about powering the amplifier.
Well, one single planned listening session unintentionally extended and prolonged from the weekend way till today as we got some firm conclusions, unanimous consensus among all present.
Two First One amplifiers, one with single SMPS1200A400, the other with dual SMPS1200A400, present. The source was Naim SuperUniti, speakers Thiel CS2.4, cabling multi UTP twisted pairs.
As usual both amps were preheated, each runing on music programme for a good hour before we compared them on five test tracks, volume leveled for each track on both sessions.
The result is not so far from our expectations, tight similarity with very slight differences noticable on momentary A-B test, otherwise, on not so closely conducted comparisons, it would be very hard or even impossible to recognize among them.
In which cases to choose single or double SMPS solution greatly depends on speaker's efficiency and impedance, these two parameters dictating how power hungry your speakers are and of course how loud you want them to be.
The ultimate and preferred First One solution is still dual mono configuration, although single SMPS completely fulfills the needs in a smaller system.
Great care has to be paid to properly conducted wiring, especially grounding as proposed in the manual. Slightly changed and optimized in chassis GND sch will be published together with DC sense circuit here soon.
Regards L.C.
Hi guys
As already explained I won't lead GB for any SMPS since there are so many producers, wishes present, also logistics around organizing resale. My decision is only to recommend the most suitable SMPS for the First One and at the same time disclaim any rumour about promoting specific one for getting provision from a certain producer. My aim here is just to let you know how to squeeze most juice from the First One module and doing that on a safe side.
Regards L.C. 😉
As already explained I won't lead GB for any SMPS since there are so many producers, wishes present, also logistics around organizing resale. My decision is only to recommend the most suitable SMPS for the First One and at the same time disclaim any rumour about promoting specific one for getting provision from a certain producer. My aim here is just to let you know how to squeeze most juice from the First One module and doing that on a safe side.
Regards L.C. 😉
I understand what You mean.I think that a lot of Persons might follw Your advice though and want to buy that SMPS1200/400.That`s why I ask if there might be a spezial Price for DIYA Members,if we ask the right Person and i thought You already had someone to talk to.
Hi you can contact Mr. Niels Burema at Hypex and explain about the GB taking place here, maybe he can help with the price if there will be enough interest.
This is the Answer from Hypex.
Hello sir,
The price you see on the webshop for the SMPS1200A400 is as low as we can get
for DIY. €150,- is already cheaper then the special SMPS600 we sell for the
NC400 modules and the SMPS1200 is twice the power of the SMPS600.
Kind regards,
Niels Burema
Sales
Hypex Electronics BV
Hello sir,
The price you see on the webshop for the SMPS1200A400 is as low as we can get
for DIY. €150,- is already cheaper then the special SMPS600 we sell for the
NC400 modules and the SMPS1200 is twice the power of the SMPS600.
Kind regards,
Niels Burema
Sales
Hypex Electronics BV
Hi, can you direct me to some link where temp coeficient of this heatsink is noticeable?
First One has 280 mA idle current (sum current per rail) so at +/-63 V module is dissipating 35,28 W idle power and that is quite a lot because it is constant, filling heatsink thermal capacity substantially, something not to underestimate at all.
Hi LC, two red beauties are here, Thanks
One question:
What about single SMPS3k instead of dual SMPS1200, sound wise ?
One question:
What about single SMPS3k instead of dual SMPS1200, sound wise ?
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