you see we are not proffesionals so everybody is trying to give an idea whith what he have available.
e202 and bryston is what i had but as i said F.O. was a lot better.
ncore on the other hand was close but if you have done some reading you will know that ncore is very highly regarded.
additionaly my comparisons was with 1.2 version and the 1.4 is much better.
the last version with f.o L front end is even better.
i would describe the sound with huge transparency but without sounding thin.
F.O. is in the high league for sure.
if i recall correct the nad m2 was 5000$ new
Hi Dominique, Link takes to a search page, can you post Brand and specs please?
Finished my First One M last week. It replaces a Hypex UcD400HG-HxR. I reused the linear Power Supply which gives 56V from a 600VA-40V transfo by channel. Decoupling uses 20.000uF by channel and by rail. I think this must be at least as good as a SMPS.
Source is: Raspberry Pi - DAC Schiit Gungnir - optical volume à la George, but with DIY digital control and auto-calibration - DCB1 - Power amp. Everything is DC-coupled. Speakers are PMC Twenty 24.
The sound now? It's a big improvement in highs. They are silk now, compared to a more harsh sound from the Hypex. The Hypex was not bad, but with the PMCs the highs weren't perfect at all (they seemed OK with Focals before). Now a cymbal sounds like the real ones. Mids are better as well, but the difference is small. Lows are there, but the perfect control the Hypex had over the woofer isn't there anymore. The output impedance seems a bit higher on the First One then on the Hypex. Still OK, and lows are very strong and clear. But they are more rounded than the Hypex. If I ever build a subwoofer, it will definitely be with Hypex-amps.
The case is rather full. There is just some space left to put VUs or a display on the front-panel in a later stage. That explains why the layout seems to be the wrong way around for 240V-cable-length.
At the moment I'm happy with the system. Instruments are more separated than on the Hypex, but the sound remained very full. Compared to a gainclone a lot better as well. Also more refined. I thought I couldn't run a big risk spending the 200 Euro on 2 modules, a lot less than 2 ncores. It's the best 200 € I've spend for an upgrade. I don't feel the need to move to ncore anymore.
Negatives? Yes. I miss the schematics. I'd like to lower the gain, but don't know what resistors to change. The amp is also very unstable in function of supply-voltage and temperature. But until now I haven't seen the woofers flying through the room, so the deviations are limited. Nevertheless I'd like to try a DC-servo, but without the schematics that's rather hard. I count on having the schematics published one day, especially since v1.4 seems obsolete now.
Source is: Raspberry Pi - DAC Schiit Gungnir - optical volume à la George, but with DIY digital control and auto-calibration - DCB1 - Power amp. Everything is DC-coupled. Speakers are PMC Twenty 24.
The sound now? It's a big improvement in highs. They are silk now, compared to a more harsh sound from the Hypex. The Hypex was not bad, but with the PMCs the highs weren't perfect at all (they seemed OK with Focals before). Now a cymbal sounds like the real ones. Mids are better as well, but the difference is small. Lows are there, but the perfect control the Hypex had over the woofer isn't there anymore. The output impedance seems a bit higher on the First One then on the Hypex. Still OK, and lows are very strong and clear. But they are more rounded than the Hypex. If I ever build a subwoofer, it will definitely be with Hypex-amps.
The case is rather full. There is just some space left to put VUs or a display on the front-panel in a later stage. That explains why the layout seems to be the wrong way around for 240V-cable-length.
At the moment I'm happy with the system. Instruments are more separated than on the Hypex, but the sound remained very full. Compared to a gainclone a lot better as well. Also more refined. I thought I couldn't run a big risk spending the 200 Euro on 2 modules, a lot less than 2 ncores. It's the best 200 € I've spend for an upgrade. I don't feel the need to move to ncore anymore.
Negatives? Yes. I miss the schematics. I'd like to lower the gain, but don't know what resistors to change. The amp is also very unstable in function of supply-voltage and temperature. But until now I haven't seen the woofers flying through the room, so the deviations are limited. Nevertheless I'd like to try a DC-servo, but without the schematics that's rather hard. I count on having the schematics published one day, especially since v1.4 seems obsolete now.
Attachments
Only finished First One products (First One Server, First One DAC/Preamp, First One Power amp) will be offered online. Stay tuned, info will be released here and on FB Shop.
First One v1.4 M is not obsolete in any respect, it will be just updated with First One L front-end, meaning better SQ.
Oenboek, First One M needs good preamp with low output impedance if you want it to be linear-neutral. I owned NC400 and the bass was less resolutive, less defined, overal not quite satisfied. I think the problem is that NC400 has 1 MOhm common input impedance, First One M 100 times lower, so your optical preamp is probably insuficient to drive FO M in this respect.
First One M output impedance is very low, is DC coupled and is linear from DC and up, so no problems to drive 2-8 Ohm loudspeakers.
The optical volume is followed by a DCB1 (Salas-design) which has an output impedance of 250 ohm. The NC400 has a very high damping factor, or very low output impedance. I guess that's the difference I hear. I've chosen the First One M because it also has a very low output impedance as for me controlling the woofer-movements is key for a detailed bass sound. Nevertheless there is a difference, although small, which is not coming from the preamp.
Check these part numbers from Digikey or Mouser
1 - Kemet ALS30A103DE063
2 - Epcos B41570E8109Q
3 - Kemet PEH200MD5100MB2
I'm aiming for # 1 which is still affordable.
10000uF 63V
ESR = 17 mOhm @ 100Hz
Ripple Current = 10.8A @ 100Hz
Impedance = 14 mOhm
Lifetime = 5000 Hrs @ 85°C
Those are really good specs for the price
Do
Hi ,
I need some advice🙂
At the moment I made a home-cinema First One V1.2 (5 pcs) and the sound is superb. High-middle clear, with a deep and accurate bass.
But, unfortunately ,(to a bias 280mA) five amplifiers heat a lot. It is possible to get down bias to 50..80 mA ?
Thank you .
I need some advice🙂
At the moment I made a home-cinema First One V1.2 (5 pcs) and the sound is superb. High-middle clear, with a deep and accurate bass.
But, unfortunately ,(to a bias 280mA) five amplifiers heat a lot. It is possible to get down bias to 50..80 mA ?
Thank you .
You can turn the bias down, but the more you do the more distortion will increase and you will limit the amount of power that is Class A to a lower amount. I think down to 230mA will not make too much difference but 50 to 80 will make quite a bit. This is designed as fairly high biased.
A bigger heatsink or a fan is the other solution.
@pinnochio
I am very very very satisfied with my EPCOS B41505A7189M000 CAP, ALUM ELECT, 18000UF, 35V, CAN in my DC Blockers.
-> http://www.diyaudio.com/forums/vend...r-achieving-0-0004-thd-n-171.html#post4386076
I know, you need 63V -> 2. Epcos B41570E8109Q
I am very very very satisfied with my EPCOS B41505A7189M000 CAP, ALUM ELECT, 18000UF, 35V, CAN in my DC Blockers.
-> http://www.diyaudio.com/forums/vend...r-achieving-0-0004-thd-n-171.html#post4386076
I know, you need 63V -> 2. Epcos B41570E8109Q
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First One Test
I have done my own test in a First One ver.1.2 module.
Is it ok to post results here?
I prefer Lazy's permission.
I have done my own test in a First One ver.1.2 module.
Is it ok to post results here?
I prefer Lazy's permission.
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Claude,
Excuse me for not being clear, but the LUA is the only one which probably betters (personal preference) the FO choosing from the Amps I owned. But a set of replacement tubes will cost a small fortune, which didn't make me happy. Furthermore they are huge and use loads of power. Unfortunately I didn't compare them 1 to 1 to FO.
NC400 I've choosen to replace the Marantz (after a lot of comparison) but I didn't like it after a while and came across the FO (1.2) and I didn't miss the NC400 up to now. Way too 'clinical' sound for me. Very nice wide and deep soundstage though.
Mark.