Hiraga "Le Monstre" 8 W

[TIC37]

I know that there is already some threads running on this subject but I have a small question not mentioned anywhere about the caps required for the power supply.

I own a Monster that was bought many years ago from Holland and it has original components on the PCB .
At that time I was not into diy that much and even less about the electronics behind things even though I have a Master in engineering. I know my physics and some electronics but had not devoted myself into building things at that time.

Ok, problem is that I had a minor accident with the amp, cause when shipped to Sweden the capacitors had been falling from their position (glued to the bottom of the case and no other support) and I, happy for my new Monster, couldn't wait to "fire" it up so due to contact between chassi and capacitor bank I had a small "fire" and some capacitors where destroyed.

Some time after this accident I met a person who said he could fix this and so he did..... by his own head and got it working but not accordingly to the original set up (the amp that I bought was not having a correct power supply either). The amp is working but I have some hum and also some undefined cracking sounds so I have now decided to do a real check up since I have starded doing my home work about electronics. The cracking sound I have isolated to bad contact somewhere in the power supply but the hum I am absolutely shure is because of the bad construction of the existing power supply.

My idea is to build the power supply accordingly to the picture below



Now my question is, the batteries are parallelled with amongst others, a supercap 0.47 F but what voltage should be choosen??
I presume I should at least have 12 V (since I am parallelling 12 V batteries) but that is getting tricky, have problem finding those values.
Any help out there??

 

[Soundhappy]

My idea is to build the power supply accordingly to the picture below

View attachment 528769

Now my question is, the batteries are parallelled with amongst others, a supercap 0.47 F but what voltage should be choosen??
I presume I should at least have 12 V (since I am parallelling 12 V batteries) but that is getting tricky, have problem finding those values.
Any help out there??

Ahoy TIC37

Very interesting project.
This is original psu schematic for " Le Monstre " from L'Audiophile by J Hiraga.
On last photo noise figure of classic psu are much higher
if compare with noise level of battery psu Have fun !

 

[Tazzz]

the main reason for humming le monstres is the lack of signal / power gnd separation on the original amp pcbs

if you want to go crazy with the psu caps use modern parts should be easy to cram 5 -10F in the same space as the original without supercaps

 

[Soundhappy]

For your psu version 12 V battery's are smaller 6Ah version and bypassed
with Nec supercapa 0,47 F decoupled in parallel with 2,2 uF polycarbonate.

 

[TIC37]

About super or ultra caps

I have everything to sgart building the power supply except for the batteries (ordered and home in a week or so) and the super/ultra caps.
Have been looking at Mouser, Digi-key, Farnell and Elfa but I dont find 0.47 F in 12, 14, 16 volt. My question is if anyone here have a clue where to find these??

 

[Soundhappy]

3 supercapa's rated 5V connected in series = 15 V is OK
Try find 10 V so you need two connected in series = 20 V is the best solution
6 or 4 scaps for this amplifier

 

[TIC37]

ohps!

True, sometimes the answer is like the foredt you don't see because of all the trees.

So used to find everything in the shops listing that you forget obvious electronic knowledge. Thank you for the help.

 

[Soundhappy]

Some supercapa have nicer longer legs for easy & stable
series solder connections make good choice

ps. type in the center are not easy to connect imo

 

[juma]

Don't waste your money, those toy caps can supply about 1mA max.
They are intended as memory back-up in low consumption circuits.

 

[Soundhappy]

Don't waste your money, those toy caps can supply about 1mA max.
They are intended as memory back-up in low consumption circuits.

Hi Juma

This Nec Supercaps are special for psu with battery only decoupling.
After research in battery psu construction NEC is described in Audiophile article
with graph and despite his limits work in this particular use.

Supercapa (G.Chrtien)

Do you have ready build battery powered amplifier or experiment with ?

 

[juma]

Good. Enjoy them...