Profet Amplifier

[Panelhead]

Saw the nice ad for the Profet amplifier in AudioXpress. Surfing around read that there is review coming.
This circuit looks extremely simple. Couple transistors, resistors, pots. The 23 dB gain is about the only downside.
Does anyone have experiance listening to this? I also read where a complete kit is available for 800.00 for the 15 watt stereo model.
This is very reasonable. But I already have everything to build one except a circuit diagram. I can build it at almost zero cost.
Saw the parts list on the Selectronic forum, wish I knew how to connect the dots.
The nice review on the website did not convert to english with babelfish. I wonder what Jean Hiraga had to say.

George

 

[nanaud]

Hi,

If you have the schemes + component list, please share.

If you would any translation from french to english, post it also, I would enjoy do it, even if my english is not so good, a human's better than a fish !!!

 

[rmgvs]

circuit diagram is no problem

It can be found at:

http://www.selectronic.fr/upload/produit/fichetechnique/4180.pdf

I also am curious about experiences with the sound of it. It can be built for reasonable costs, a pcb is not required.

Reading the instructrions I wonder what use are the use of 2 trimpots. I looks like one is for the offset regulation and the other for the current regulation. This seems not logical to me: one pot could do for the offset and the current can be set by changing the 1k resistors (like in the Le Monstre design of Jean Hiraga).

Please comment, because I am not sure.

Be aware that the instruction in pdf format is about 45 Mb!

 

[jam]

rmgvs,

Do you have the link for the Grand Mos 100w/ch amp. manual?

Regards,

Jam

 

[fab]

Profet Grand mos really Class A ?

I have read the doc on the Grand mos. It says to be "pure class A" at 16 WRMS for 8 ohms. From my calculations, it takes 1 A bias current for class A but the doc indicates to adjust it to about 260 mA. Thus, is there something I get wrong or is this false advertisement about class A?

 

[JohanH]

Grand Mos schematic

Hello Jam,

Grand Mos schematic can be found here:

http://perso.wanadoo.fr/francis.audio2/Grand_Mos.jpg

Cheers,
Johan

 

[jacco vermeulen]

All in one:

http://www.selectronic.fr/includes_selectronic/pdf/Grand_MOS_Revue_son1.pdf

or two:

http://www.selectronic.fr/includes_selectronic/pdf/Grand_MOS_Revue_son2.pdf

Very popular design in France, sounds quite good.

 

[Panelhead]

Wrong amp

All in one:

http://www.selectronic.fr/includes_selectronic/pdf/Grand_MOS_Revue_son1.pdf

or two:

http://www.selectronic.fr/includes_selectronic/pdf/Grand_MOS_Revue_son2.pdf

Very popular design in France, sounds quite good.

Jacco,
Those are the 100 watt Gran Mos. The Profet is a 25 watt, much simpler model.
The Profet uses an opamp input, a 2K170, 2SJ74 pair, and a pair of lateral mosfets. I can figure out the discrete, have no idea on the use of the opamp.

George

 

[jacco vermeulen]

afaik, the Grand Mos Profet circuitry is the same as the one for the Triphon.
The Profet kit comes with RCA and balanced XLR entry, for balanced entry you need the opamp.

 

[destroyer X]

Ufa!...i am already downloading!.... my God!

Enormous the file..... oh!

c'a marche!

regards,

Carlos

 

[JohanH]

The review is here

http://www.audioxpress.com/reviews/media/hansen2580.pdf

Cheers,
Johan

 

[gaborbela]

Hi all
I just wondering if someone has experience with these amp , or someone built already .
I'm planing to build these amp , so any advise would be good .
At the next week I will do the pc boards for it and buy the parts ..
If somebody know were I can purchase ECX10N16 or 20 & ECX10P16 or 20 please let me know .
I would like to use these type of lateral mosfets because a lot of fake 2SK1058 & 2SJ162 out there .
Thanks
Regards

 

[forr]

The Profet sounds like an amplifier with an output impedance of 6.8 Ohm. Take any standard amplifier, add a 6.8 Ohm power resistance in series with the output before attempting any comparison which could'nt be fair otherwise.

 

[Panelhead]

Read the review

It was reviewed a couple months back. The measured specs were way off from published. It fact, not very good.
I collected the parts to build a clone. But the review not not impress. Might sound great, but prefer solid state amps that measure good and sound great.

George

 

[forr]

Forr
---add a 6.8 Ohm power resistance---
Add a 6.8 Ohm power resistor, I mean.

 

[ilimzn]

I would like to use these type of lateral mosfets because a lot of fake 2SK1058 & 2SJ162 out there .

Can you tell us more about these J162/K1058 fakes? I wasn't aware they were being faked. Being lateral MOSFETs, the silicon in use is fairly unique and relatively easy to test even with a DVM that has a diode test setting (the low treshold makes this fairly easy).

 

[vizion]

just curious. Is the selectronic profet single ended or pp ?

 

[forr]

Hi Vizion,
It's a four transistor push-pull amp : complementary input pair, complementary output pair

 

[vizion]

thanks forr.

 

[jacco vermeulen]

Those with a sense of irony might name it a PF4.
Inspirational, a "trois hommes et un coffin" of audio.