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First One - mosFET amplifier module

20171109_204057.jpg

Not good
 
LC or any one else can you please answer my question

Can you confirm if the FO 1.4L amplifier modules in full balanced stereo configuration would be the same as the drawing in post #95.
Would 85v be ok?
Also -neg not connected due to it being internally connected to ground ?

85 V from + to - or from + to GND or from GND to - or ...? Why 85 V? Do the math +/- 85 V would bring 2800 W rms/4 Ohm and that would vaporize the modules.
If you don't want to burn the modules do exactly what sch is telling you. I can not explain sch if you do not understand basics. Everything is marked and specified on the sch, why change it?
 
proton28

Here is a power supply for 1.4L.
Based on this thread and to be in safe zone, maximum voltage for 1.4L can be +/- 85V.
Also here is a pdf for 1.4M....for reference.

Lazy Cat....
I still wait your email.....
Hmm...I wondering if I needed to replace the modules.....how long will take ONLY to respond.....
 

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On first page is mentioned very clear:
Supply voltage for 1.4 L................................... +/-45 to +/-85 V.

Also you have (for reference only) ,previous post of mine, a complete power supply.
I would go for double mono configuration.
Shottky fast rectifiers,two x 1KW power transformers (custom made for very low noise) and 2 x 100 000 uf/100V,follow by 2 x 100uf/250V and snubbers.
At this moment you can begin measurements of the low ripple at the power supply.
 
Lazy cat,
The sch was for “Medium” modules.
What voltage do you recommend if using “Large” modules ?
I’m surprised that you recommend same voltage for ”Medium” and “Large” modules
+/-55 V is absolute max. voltage for bridging FO L modules. Output power is proper to voltage square function, so it rises exponentially, meaning at +/-55 V PSU there will be (voltage drop on power devices subtracted) 90 Vp on 4 Ohm load and that is a lot (1012 W rms/4 Ohm). SOAR of output devices should be strictly respected, not to mention thermal considerations with heatsinking, etc. All in all take great care at amp bridging.
 
It would be nice to have sonic comparisons of SMPS vs old school PS like the one mentioned... I quite like old school :)

I understand the SMPS are more efficient, smaller, lighter, possibly cheaper and more importantly also perhaps they can deliver quicker current, so that can be a big plus.

On the negative, the longevity of these seems a big question mark, no way to repair them easily, not to mention HF rubbish or what may happen if (when?) they fail...

But the big question is: can a conventional (full grown) PS equal or beat the Hypex & Co (with the already proven additional big caps)?

Has someone performed comparisons? LC perhaps?
 
The discussion on SMPS vs linear supply popped up before, for example in the NC400 thread.
The problem is that not all SMPS's are the same, and this is also the case with linear supplies.
Especially with power amps which draw alternate current from the power supply these differences can become more apparent.
For example an unregulated linear power supply with 1 ohm of DCR compared with another linear supply with 2 ohm of DCR. When the amplifier draws current peaks along with the music, the higher DCR supply will cause more voltage drop on the supply lines and the amplifier will sound more compressed.
SMPS have their own peculiarities; not all of them are regulated.
Conclusion can be that a good comparison between old and new school is not easy to do.
 
Yes I know, hence me asking :)

However, most threads I have read are indeed linear supply vs SMPS... but on class D amps (Hypex & co)

That is IMHO not relevant here as Class D pump current differently / in a different manner on the PS, hence IMHO not really "telling the answer" when it comes to trying to evaluate them for FO amps - or any Class A/B amp.

I would rather like to read reports re different PS for this FO amp... But that is all IMHO, glad to be proved wrong.

Claude
 
I have heaRD the difference WitH other modules ( Hypex Ncore) I and all the others on the room prefered " OLD SCHOOL".

Some guys from the forum managed to visit Audio Video Show 2017 - Warsaw. Today still possible to hear our system, warmly welcome.
 

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