First One - mosFET amplifier module

[coolewater]

Hi
I've built some cfa Amplifiers. Among others, the nx amplifier and kits from Jims Audio. I am glad to try the "first one Amplifier".
What is the difference in Sound between SMPS power supplies and a conventional supply? First one is a fast amplifier. I suspect CFA is sensitive to the supply voltage. SMPS creats HF - interference on the supply.
Regards Gerd

 

[danny_66]

There will be three SMPS tested and recommended, each with its significant features which will be fairly revealed and presented in this thread.

Great !
That will be interesting 🙂

What is the difference in Sound between SMPS power supplies and a conventional supply?

Noise floor lower + more dynamic with SMPS, here are some measurements.
Sounds better too.

 

[AP2]

Good Morning Amateurs,
Just for curiosity, since I posted the same measure with the DPS-500 / S.
Now equally at 4R but with DPS-500/DA. (new release of DPS-600 as Owen thread measures).
Yes, I know that I insist with the DPS-500/DA, but I have good reason (aside from you can save 100 € approximately) same PCB, same components, except the power-units, compared with the "S" version.
Depends on usage at home, can be a good choice.
The strong point remains the transient response, and the purity of the output voltage, with the lowest (not usual) low EMI / RFI, not possible with traditional smps using a PWM as regulation.

Wow!!..today I have time for DPS-500 thread 🙂

 

[meanman1964]

I'm planning to perform a test with toroid and PSU regulator from Thel Audio

 

[androuski]

I'm out, I've changed my plans. Have fun 🙂

Hi, just added my order to the list

luca 4
danny_66 2
woofertester 4
rainerco 2
pinnocchio 4
giannettino 2
jokari69 2
mksung 2
ZZoran 2
Edgar 2
Eric06 2
kimon 2
maxidcx 2
e-bok 6
bobo le chat 2
metallicus69 6
scoutOne 4
Iduarte1973 2 (full kit)
quan 2
Greg Stewart 2
colesey 2
analogsa 4
Brianco 2 (chassis)
Theodosis O. 4
chunek 2
Darb 4 (1-2 x full kit, depend on price...)
CaféNoir 4
Nikitas 2 (full kit)
meanman1964 2
supernet 2
jeremysk 2
Dane 2
mikvous 2
PreSapian 2
coolewater 2
edionysus 2 (full kit)
jaggel 2 (full kit)
fredlock 2
HiroPro 2 (full kit)
darbost 2
Turbon 2 (full kit)
r8833 2
DrizztDo 2 (full kit)
androa76 2 (full kit)
JethroTull 2
stonehome 2 (full kit)
commstech 2
we417 2
hcbonfim 2
stormsonic 2 (full kit)
fishball79 4

 

[Esperado]

I suspect CFA is sensitive to the supply voltage. SMPS creats HF - interference on the supply.

Yes, unless some special precautions taken by the designer, like cap multipliers in the power rails of the input + voltage amplification stages, a CFA is more sensitive to supplies ripples *at low frequencies.*
Is is not so obvious SMPS create more HF than conventional PSUs.
The big trafo of PSU is more prone to HF leakeage from AC plug. The rectifiers often create reasoning peaks up to very high frequencies, not so easy to damp.etc...
SMPS need some building precautions against switching frequency leakages, (Good schields) but i noticed, long years ago, a clear benefit on audio quality, using them, that you can measure too. This had been correlated several time, but, of course, depend on the PS used, quality of the caps, kind of regulation etc.
And, because a SMPS is cheaper, more efficient, lighter, smaller, easier to be fixed in a case, it would be stupid to chose something else.
About regulation VS not regulated ones, i reserve, as L.C. my opinion, too many factors involved. I believe the best should be to try several SMPS and chose the best sounding one, or the best price if they are close, on a pure audio point of view.
I will trust the L.C. ears and his quest for quality, on this point, and am very interested to read his conclusions.

 

[giannettino]

luca 4
danny_66 2
woofertester 4
rainerco 2
pinnocchio 4
jokari69 2
mksung 2
ZZoran 2
Edgar 2
Eric06 2
kimon 2
maxidcx 2
e-bok 6
bobo le chat 2
metallicus69 6
scoutOne 4
Iduarte1973 2 (full kit)
quan 2
Greg Stewart 2
colesey 2
analogsa 4
Brianco 2 (chassis)
Theodosis O. 4
chunek 2
Darb 4 (1-2 x full kit, depend on price...)
CaféNoir 4
Nikitas 2 (full kit)
meanman1964 2
supernet 2
jeremysk 2
Dane 2
mikvous 2
PreSapian 2
coolewater 2
edionysus 2 (full kit)
jaggel 2 (full kit)
fredlock 2
androuski 2
HiroPro 2 (full kit)
darbost 2
Turbon 2 (full kit)
r8833 2
DrizztDo 2 (full kit)
androa76 2 (full kit)
JethroTull 2
stonehome 2 (full kit)
commstech 2
we417 2
hcbonfim 2
stormsonic 2 (full kit)

Sorry..i have to leave..have fun with this little great amp..
Regards
Gianni

 

[audiostar]

The reason why the First One uses no transformer?

 

[MASantos]

The reason why the First One uses no transformer?

It can use a traditional transformer and capacitor bank, but according to lazy cat it performs best with a switch mode power supply such as the ones talked about in this tread. These psu's also allow for the low height chassis shown.

 

[sebbyp]

I cannot see this being mentioned throughout the post. Are the dimensions of the chassis available? Need to know it can fit where I intend it to before I commit to a full kit.

 

[hcbonfim]

Hi ,
After building many diy amps (VSSA, GB150D, Alephs, DX AMP, M400.etc) my next project is this Firts One. How sound these diy amps compared to comercial amps like Musical Fidelity M6I, ARCAM A38, Cambridge audio 851A, Marantz PM11s3 ? They can win this models in a blind test ?

cheers

 

[Esperado]

After building many diy amps (VSSA, GB150D, Alephs, DX AMP, M400.etc) my next project is this Firts One. How sound these diy amps compared to comercial amps

What is your opinion about VSSA in this comparison ?

 

[hcbonfim]

Hi Esperado,
I didn't listen none of these models above only reviews in a brazilian forum,
next month i will test the Cambridge and Marantz,
cheers

 

[metallicus69]

Adjusting the quantities to only 2.

luca 4
danny_66 2
woofertester 4
rainerco 2
pinnocchio 4
jokari69 2
mksung 2
ZZoran 2
Edgar 2
Eric06 2
kimon 2
maxidcx 2
e-bok 6
bobo le chat 2
metallicus69 2
scoutOne 4
Iduarte1973 2 (full kit)
quan 2
Greg Stewart 2
colesey 2
analogsa 4
Brianco 2 (chassis)
Theodosis O. 4
chunek 2
Darb 4 (1-2 x full kit, depend on price...)
CaféNoir 4
Nikitas 2 (full kit)
meanman1964 2
supernet 2
jeremysk 2
Dane 2
mikvous 2
PreSapian 2
coolewater 2
edionysus 2 (full kit)
jaggel 2 (full kit)
fredlock 2
HiroPro 2 (full kit)
darbost 2
Turbon 2 (full kit)
r8833 2
DrizztDo 2 (full kit)
androa76 2 (full kit)
JethroTull 2
stonehome 2 (full kit)
commstech 2
we417 2
hcbonfim 2
stormsonic 2 (full kit)

 

[Catal]

Hello,
I'm in for 4 modules.

luca 4
danny_66 2
woofertester 4
rainerco 2
pinnocchio 4
jokari69 2
mksung 2
ZZoran 2
Edgar 2
Eric06 2
kimon 2
maxidcx 2
e-bok 6
bobo le chat 2
metallicus69 2
scoutOne 4
Iduarte1973 2 (full kit)
quan 2
Greg Stewart 2
colesey 2
analogsa 4
Brianco 2 (chassis)
Theodosis O. 4
chunek 2
Darb 4 (1-2 x full kit, depend on price...)
CaféNoir 4
Nikitas 2 (full kit)
meanman1964 2
supernet 2
jeremysk 2
Dane 2
mikvous 2
PreSapian 2
coolewater 2
edionysus 2 (full kit)
jaggel 2 (full kit)
fredlock 2
HiroPro 2 (full kit)
darbost 2
Turbon 2 (full kit)
r8833 2
DrizztDo 2 (full kit)
androa76 2 (full kit)
JethroTull 2
stonehome 2 (full kit)
commstech 2
we417 2
hcbonfim 2
stormsonic 2 (full kit)
Catal 4


Frank

 

[Lazy Cat]

First One GB list update

OK, GB members list edited and checked.

Please continue from this list on. 😉

New GB member copy this list and please add your name at the bottom.

Thanks. Regards.



luca 4
danny_66 2
woofertester 4
rainerco 2
pinnocchio 4
jokari69 2
mksung 2
ZZoran 2
Edgar 2
Eric06 2
kimon 2
maxidcx 2
e-bok 6
bobo le chat 2
metallicus69 2
scoutOne 4
Iduarte1973 2 (full kit)
quan 2
Greg Stewart 2
colesey 2
analogsa 4
Brianco 2 (chassis)
Theodosis O. 4
chunek 2
Darb 4 (1-2 full kit)
CaféNoir 4
Nikitas 2 (full kit)
meanman1964 2
supernet 2
jeremysk 2
Dane 2
mikvous 2
PreSapian 2
coolewater 2
edionysus 2 (full kit)
jaggel 2 (full kit)
fredlock 2
HiroPro 2 (full kit)
darbost 2
Turbon 2 (full kit)
r8833 2
DrizztDo 2 (full kit)
androa76 2 (full kit)
JethroTull 2
stonehome 2 (full kit)
commstech 2
we417 2
hcbonfim 2
stormsonic 2 (full kit)
fishball79 4
Catal 4

 

[Lazy Cat]

First One professional measuring station modules finished, just about to install them in a 19" rack chassis. 😎

 

[maxlorenz]

I was about to comment several times that your workstation looks very different from mine...much cleaner 😀

Best wishes for your project.
M.

 

[_henry_]

i wonder why SMPS600 is there 😀

 

[Lazy Cat]

I was about to comment several times that your workstation looks very different from mine...much cleaner 😀

Best wishes for your project.
M.

Doing it slowly since it's proto PCB, nevertheless its functionality is still perfect. Measuring station module will measure all necessary values, generate three function signals, safely start up the procedure, includes all current and over/under voltage protections, discharge First One after calibration and testing, etc.

i wonder why SMPS600 is there 😀

Inside measuring station I need +/-63 V to supply DUT (device under test) which is happen to be First One module. 😀