• These commercial threads are for private transactions. diyAudio.com provides these forums for the convenience of our members, but makes no warranty nor assumes any responsibility. We do not vet any members, use of this facility is at your own risk. Customers can post any issues in those threads as long as it is done in a civil manner. All diyAudio rules about conduct apply and will be enforced.

First One - mosFET amplifier module

Here we go

Matched quartets ready to be placed into FO L modules :)

L.C. :cheers:
 

Attachments

  • IMG_0886.jpg
    IMG_0886.jpg
    507.9 KB · Views: 607
grounding and temperature

I wanted to ask which method of grounding is preferred, the one provided by the 1.4 version manual (no additional wire to the ground with the extra diodes/resistor) or the one given in the picture below (IIRC, it's improved version of the 1.2 version)
420596d1401135623-first-one-mosfet-amplifier-module-first-one-stereo-connection.png


Also, is it 50C idle and 53C while playing music temperature something to worry about ?
Take to account that it's winter and summer is quite warm down here (Greece)

BTW, sounding great, while I've heard better amps in some aspects of overall performance (mainly bass), none comes close to the value for money of this one
...and as for the bass (only lost against a very well regarded amp in this category) I'm going active in some days so it's not a closed case yet
 
Having played now with five SMPS I can declare that very decent sound can be obtained from them, provided you increase output capacitance or use a power regulator, like the only one I know and use, the PowerReg, from Teddy Pardo.
I recommend a minimum extra of 10mf per rail per channel (NTC thermistor in series with primaries), better use non-regulated SMPS, and the bigger the better, within reasonable sizes.

I have not used all MFRS, but Connex and Hypex. I can asure that the SMSP800RE from Connex is not bad at all...it lacks DC error sense, though.

It ended a little crowded inside. :D
 

Attachments

  • FO 1.4M extra CAP.JPG
    FO 1.4M extra CAP.JPG
    934.8 KB · Views: 394
  • FO 1.4M extra CAP2.jpg
    FO 1.4M extra CAP2.jpg
    1,003.6 KB · Views: 381
Having played now with five SMPS I can declare that very decent sound can be obtained from them, provided you increase output capacitance or use a power regulator, like the only one I know and use, the PowerReg, from Teddy Pardo.
I recommend a minimum extra of 10mf per rail per channel (NTC thermistor in series with primaries), better use non-regulated SMPS, and the bigger the better, within reasonable sizes.

I have not used all MFRS, but Connex and Hypex. I can asure that the SMSP800RE from Connex is not bad at all...it lacks DC error sense, though.

It ended a little crowded inside. :D


Hi,
Thanks for the feedback.

At the end how would you rate the sound quality of each SMPS?
Are there any big sonic differences or is all nuances once you increase output capacitance?

Regarding the Super Power Regulator, how does it perform vs an increase of capacitance? I must confess, increasing capacitance seems to me much easier and I would have thought regulators would have been too slow or provide not enough current...

Thanks again

Claude
 
Hi guys,

What's that?

A voltage regulator for high power circuits.
There are many. I have used only one class (Power reg) and stuck with it because it works fine. Only used in "chipamps" and low voltage class A amps, including a V-FET single ended class A amp, very recently, with which it works great.

Here's the link:
Introducing the PowerReg - pink fish media

At the end how would you rate the sound quality of each SMPS?
Are there any big sonic differences or is all nuances once you increase output capacitance?

Regarding the Super Power Regulator, how does it perform vs an increase of capacitance? I must confess, increasing capacitance seems to me much easier and I would have thought regulators would have been too slow or provide not enough current...

First, about regulation v/s non-regulation, stick with the inventors recommendation, which in the case of F.O. 1.4M is non-regulated supply. ;)

I use PowerReg in lower quality amps or when I want to save on caps.
I have used it on my Hypex UCD class D amps and did not find any difference so I removed them.

Second, about SMPS differences, it is hard to say because the better connex (SMPS800RE) was used on a chinese LME49810 based bipolar class B amp. Anyway, both SMPS with increased capacitance improved a lot, with not only better bass but also better bass harmonics, more dense images, more ambient sound (and ambient noises), with the Hypex sounding more tight and precise and the Connex sounding more relaxed or romantic...but it could be well a difference in the amp modules themselves as you can understand.
I referred previously about listening to the FO as like wearing a magnifying glass; adding more capacitance is like using a more potent magnifying glass...

FO has now extra Elna 10mF//Russian polystyrene 250nF per rail. I had no space to put one extra 1uF polystyrene. :bawling:

I hope this helps.
M.
 
Hi guys,



A voltage regulator for high power circuits.
There are many. I have used only one class (Power reg) and stuck with it because it works fine. Only used in "chipamps" and low voltage class A amps, including a V-FET single ended class A amp, very recently, with which it works great.

Here's the link:
Introducing the PowerReg - pink fish media



First, about regulation v/s non-regulation, stick with the inventors recommendation, which in the case of F.O. 1.4M is non-regulated supply. ;)

I use PowerReg in lower quality amps or when I want to save on caps.
I have used it on my Hypex UCD class D amps and did not find any difference so I removed them.

Second, about SMPS differences, it is hard to say because the better connex (SMPS800RE) was used on a chinese LME49810 based bipolar class B amp. Anyway, both SMPS with increased capacitance improved a lot, with not only better bass but also better bass harmonics, more dense images, more ambient sound (and ambient noises), with the Hypex sounding more tight and precise and the Connex sounding more relaxed or romantic...but it could be well a difference in the amp modules themselves as you can understand.
I referred previously about listening to the FO as like wearing a magnifying glass; adding more capacitance is like using a more potent magnifying glass...

FO has now extra Elna 10mF//Russian polystyrene 250nF per rail. I had no space to put one extra 1uF polystyrene. :bawling:

I hope this helps.
M.

Why not just transformers and Capacitors.
 
Why not just transformers and Capacitors.

SMPS's energy/time transfer to secondary caps (read transients, natural dynamic - current on demand) is way better and as such very audible.

Yeah, sorry I could not refrain. Besides this is DIYA and we are allowed (and supposed) to try every PS-circuit-cable-connector...etc, we imagine to suit our taste or experiment. (just see my speaker connection, if you can, from the bad pics)

I plan to build a conventional linear supply powered FO (50mF per rail) just to convince me which approach is better, as I already had the parts.

Anyway, when we are building 10 different amps, we seek cheaper and more efficient power alternatives. :eek:

Cheers,
M.