Hi, sorry for being a newbie, thus dependent on information from more knowledagble gurus 
LC, You stated somewhere that using a smaller PSU would make the F.O. better suited for low-impedance loads. I´m aiming at 2 X Cresnet´s 600w +/-55V SMPS, speakers about 3 ohms (due to 2 woofers paralleled).
Think I will be ok with F.O. "M" version (provided I follow the heatsink recommendations)- or better to wait for "L" version?
Tia, Finn
LC, You stated somewhere that using a smaller PSU would make the F.O. better suited for low-impedance loads. I´m aiming at 2 X Cresnet´s 600w +/-55V SMPS, speakers about 3 ohms (due to 2 woofers paralleled).
Think I will be ok with F.O. "M" version (provided I follow the heatsink recommendations)- or better to wait for "L" version?
Tia, Finn
Hi Finn
You're just about right with your estimation. As you can see in upper post #2832 from Robert, he uses the same Cresnet's SMPS with great success. 3 Ohm from two bass drivers in parallel is a piece of cake for FO v1.4 M. The only thing to consider is to have 0,5 °K/W (or less) heatsink for each module, otherwise no restrictions.
It is also wise to connect DC sense module (one per channel) to shutdown SMPS in a case of FO failure (DC on SPK OUT).
Browse this page and few pages back to see pictures of Robert's amp and Black Mamba inside details.
Best regards, L.C.
You're just about right with your estimation. As you can see in upper post #2832 from Robert, he uses the same Cresnet's SMPS with great success. 3 Ohm from two bass drivers in parallel is a piece of cake for FO v1.4 M. The only thing to consider is to have 0,5 °K/W (or less) heatsink for each module, otherwise no restrictions.
It is also wise to connect DC sense module (one per channel) to shutdown SMPS in a case of FO failure (DC on SPK OUT).
Browse this page and few pages back to see pictures of Robert's amp and Black Mamba inside details.
Best regards, L.C.
Thanks very much, LC! (Just about ready to order
Ah, that´s what those small PCB´s at speakerterminals are
Can they be ordered with the F.O modules?
Regards, Finn
Ah, that´s what those small PCB´s at speakerterminals are
Can they be ordered with the F.O modules?
Regards, Finn
Overkill Audio,
Thanks review and for reviews other members a thanks too, look forward listening latest version intend join when small version is released and maybe also try to bridge that version.
Lazy Cat,
Thanks these must have modules, is it time now that so many have got a super amp and reported back that you release measurements : ) look forward see this new version without feedback cap topology show super flat time component in square waves all down from DC and up sky high > zobel smoke
Thanks review and for reviews other members a thanks too, look forward listening latest version intend join when small version is released and maybe also try to bridge that version.
Lazy Cat,
Thanks these must have modules, is it time now that so many have got a super amp and reported back that you release measurements : ) look forward see this new version without feedback cap topology show super flat time component in square waves all down from DC and up sky high > zobel smoke
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I hope i'm not late for the party and i would like to get a 1.4m version for my ears. I have a pair of Mackie MRmk3 studio monitors for which I would like to beef up the amp.
I read a lot of positive comments and I share the users enjoyment regarding this project and want to try one of your great amp. I'm sure I will be satisfied another module will be needed soon.
I read a lot of positive comments and I share the users enjoyment regarding this project and want to try one of your great amp. I'm sure I will be satisfied another module will be needed soon.
Hi
Smoothquark, the choice for enclosure is a nightmare as long as you try to make it smaller and nice. The decision to go with 2 monoblock, is great but will increase the cost. The very minimum for such a project would be this case which is a new version half size of the usual "dissipante" model, you can find it here for example:
Hifi 2000 Botier avec Dissipateur 2U 300mm Faade 10mm Noire - Audiophonics
it is 240mm large and then 150mm internal.
you can mount the SMPS on one heatsink, say right, and the FO on the other heatsink, say left.
with such a configuration and an SMPS1200A400 (62V) you ll get a temperature of around 52-55°C depending on the overall conduction between the 2 heatsink.
My choice was to put 2 FO in the box, and the SMPS located on the front panel. But the SMPS is 165mm large so you have to make your own custom encloseure which is not a problem : I bought the same front panel 240mm wide here:
hifi 2000 - facade aluminium 10mm noire pour gx283-287-288
and 2 standard heatsink 2Ux300m which you just have to drill properly so they can be mounted together on the front panel at 90°.
Then you ll have to find a later solution for the lower, upper and rear panel, but you can make you personal touch with some nice wood for example. good luck, But do not underestimate the size of the heatsink, or lower down the SMPS for a 1200A180...
Thank you. Sorry for the rather late reply.
First One L PCB design completed
Good news guys, next week First One L goes in pre-production, four prototype modules will be tested thoroughly. First One L acceptance of +/-85 Vdc max. power supply will give enough headroom even at low efficiency speakers to produce undistorted high SPL. High hopes on L version includes same sound signature as M at double output current & power capability and only 6 cm longer PCB.
Good news guys, next week First One L goes in pre-production, four prototype modules will be tested thoroughly. First One L acceptance of +/-85 Vdc max. power supply will give enough headroom even at low efficiency speakers to produce undistorted high SPL. High hopes on L version includes same sound signature as M at double output current & power capability and only 6 cm longer PCB.
Good news guys, next week First One L goes in pre-production, four prototype modules will be tested thoroughly. First One L acceptance of +/-85 Vdc max. power supply will give enough headroom even at low efficiency speakers to produce undistorted high SPL. High hopes on L version includes same sound signature as M at double output current & power capability and only 6 cm longer PCB.
Sounds great, what is the price & delivery time? Recommended PSU voltage?
Hi Derek
I'm glad your DB listening tests fulfilled high expectations. Competitors are fearsome but ..
L.C.
Overkill Audio,
Thanks review and for reviews other members a thanks too, look forward listening latest version intend join when small version is released and maybe also try to bridge that version.
Lazy Cat,
Thanks these must have modules, is it time now that so many have got a super amp and reported back that you release measurements : ) look forward see this new version without feedback cap topology show super flat time component in square waves all down from DC and up sky high > zobel smoke
L done, S is next.
It's too early at this stage, first I have to listen to L to see on what level it will qualify.
Black Monolith is rising
As announced in below's post, some preliminary pics of Black Monolith rising, just a teaser for the moment.
As announced in below's post, some preliminary pics of Black Monolith rising, just a teaser for the moment.
First One Black Monolith monoblock chassis is coming to assembly this week. It will be impressive in its simplicity, still fully functional as Black Mamba.
Black Mamba and Black Monolith will be available as ready made products as well.
L.C.
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