If you choose to use it - make a seperate power supply box and you will probably be OK.
Just remember - a correctly adjusted Le Monstre draws just 29Watts of constant power, with a comfortable safety margin of 4x rating that still only requires a 120VA transformer.
Shoog
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I didn't like the AX. I gave the boards to a friend on this forum and am using the heatsinks for my Slewmaster project. This amp looks interesting and wanted to compare it to my JLH and KSA50. I may take a chance on it anyway. Are there any foil patterns around for iron transfer?
Thanks, Terry
Thanks, Terry
One more here
I know many DIY-ers use these layout with out any issue
amplificateur 8W le monstre - Page 4 sur le forum Amplification du site Homecinema-fr.com - 29735872 - 1056
Also here you have a regulated PS if you would like to test that.
I prefer CRC or CLC over the regulated.
I know many DIY-ers use these layout with out any issue
amplificateur 8W le monstre - Page 4 sur le forum Amplification du site Homecinema-fr.com - 29735872 - 1056
Also here you have a regulated PS if you would like to test that.
I prefer CRC or CLC over the regulated.
Juma's cubie
Hi Terry,
The latest amp from Juma is named Cubie and it would fit good for your voltages. He is only using a 200VA for a stereo amp...but still I would give it a shot if I had your transformer
http://www.diyaudio.com/forums/pass-labs/258666-cubie-small-f5-variant-gr-grade-jfets-latfets.html
Rgds,
Eric
Hi Terry,
The latest amp from Juma is named Cubie and it would fit good for your voltages. He is only using a 200VA for a stereo amp...but still I would give it a shot if I had your transformer
http://www.diyaudio.com/forums/pass-labs/258666-cubie-small-f5-variant-gr-grade-jfets-latfets.html
Rgds,
Eric
Hi Shoog,
So a 200VA for a stereo set would be OK ?
I was thinking of using that transformer for a stereo amp. (Digikey part no. 237-1346-ND)
Invalid Request
29W / 2 is 14.5W per channel and if powered at +/- 12Vdc it would mean a bias of 0.6A...the kit I'll be using is from Jim's Audio and the bias resistor are 470ohm instead of the original 1Kohm. Should I replace these with 1Kohm ?
I was always very fond of the Hiraga sound, can't wait to hear mine
Thanks guys,
Eric
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OK, I etched some boards for the Hiraga. I'll drill them tomorrow. I have the JFETs ordered so can populate next week. I have a beefy SMPS that it +-12v I may try as well.
I'll read up on that cubie. I wasn't a fan of that AX but Nelson has fan club so there must be something to his designs.
Blessings, Terry
I'll read up on that cubie. I wasn't a fan of that AX but Nelson has fan club so there must be something to his designs.
Blessings, Terry
Attachments
Hi Shoog,
So a 200VA for a stereo set would be OK ?
I was thinking of using that transformer for a stereo amp. (Digikey part no. 237-1346-ND)
Invalid Request
29W / 2 is 14.5W per channel and if powered at +/- 12Vdc it would mean a bias of 0.6A...the kit I'll be using is from Jim's Audio and the bias resistor are 470ohm instead of the original 1Kohm. Should I replace these with 1Kohm ?
I was always very fond of the Hiraga sound, can't wait to hear mine
Thanks guys,
Eric
If I were going to buy a transformer and only need 200VA I'd probably go with Antek
AS-2212 - 200VA 12V Transformer - AnTek Products Corp
Nice work with your PCB. Can I ask you about your power supply, I guess a bench top PS could do the trick just to try this amp.
Rgds,
Eric
After thinking about it, I would do the same but would buy the AS-2215 just in case I need to use a capacitance multiplier which requires a voltage drop of 4-5V.
I'm aiming for slightly more power, around 10-12W would be ideal for my need.
Rgds,
Eric
Terry please pay att. to the transistor pin out.
Since to me one or two piece must be rotated 180 degree. Just follow the circuit that case you avoid any mistake
If you look at the solder mask where you took the layout some red marks there.
Greetings Gabor
For the Le Monstre the good PS is very important!
i would say that would be a good candidate transformer.Hi Shoog,
So a 200VA for a stereo set would be OK ?
I was thinking of using that transformer for a stereo amp. (Digikey part no. 237-1346-ND)
Invalid Request
29W / 2 is 14.5W per channel and if powered at +/- 12Vdc it would mean a bias of 0.6A...the kit I'll be using is from Jim's Audio and the bias resistor are 470ohm instead of the original 1Kohm. Should I replace these with 1Kohm ?
I was always very fond of the Hiraga sound, can't wait to hear mine
Thanks guys,
Eric
The biasing resistor will be different to the original since the gm of the jfets is different with the modern versions (unless you are using vintage ones). I found that I had to simulate the circuit to get the correct bias resistor values and even then I had to adjust them when I did the final build out.
Shoog
Hi Guys,
I drilled the boards today and began populating them. I don't have the original devices so My first plan was to follow the devices in the thread that was linked to earlier which is where I got the foil pattern from. He suggests BC550/560 for the small BJT transistors but doesn't give the grade. So that got me looking at the spec sheets. The closest devices that I could find, and that I have on hand were the KSC1845E/A992E. The other thing that he didn't mention is that the pinout is different for the BCxxx and the legs would have to be twisted to fit. So here are some questions for those of you who may have substituted parts.
1) Are the KSC1845E/KSA992E a good replacement for the small BJT devices?
2) On this board layout, there are two 47uf and two 100nf caps that aren't on the schematic. Have you guys utilized those?
3) He changed the JFET to 2SK246/J103 and the 1K resistors to 390R. IS the 1K changed because of the JFET change?
4) I have both the 2SK246/J103 and the 2SK170/J74 ordered. Is there a preference on these?
Thanks, Terry
I drilled the boards today and began populating them. I don't have the original devices so My first plan was to follow the devices in the thread that was linked to earlier which is where I got the foil pattern from. He suggests BC550/560 for the small BJT transistors but doesn't give the grade. So that got me looking at the spec sheets. The closest devices that I could find, and that I have on hand were the KSC1845E/A992E. The other thing that he didn't mention is that the pinout is different for the BCxxx and the legs would have to be twisted to fit. So here are some questions for those of you who may have substituted parts.
1) Are the KSC1845E/KSA992E a good replacement for the small BJT devices?
2) On this board layout, there are two 47uf and two 100nf caps that aren't on the schematic. Have you guys utilized those?
3) He changed the JFET to 2SK246/J103 and the 1K resistors to 390R. IS the 1K changed because of the JFET change?
4) I have both the 2SK246/J103 and the 2SK170/J74 ordered. Is there a preference on these?
Thanks, Terry
This look like a nice regulator, could this do the trick ;
LOW Noise High Current Dual Power Supply LT1083CP KIT | eBay
Thanks,
Eric
LOW Noise High Current Dual Power Supply LT1083CP KIT | eBay
Thanks,
Eric
Hi Terry.
I can tell you that compared to my (still limited) experience with this fantastic amplifier, capacitors 47uf and 100nf could serve to stabilize the circuit. (for my amplifier, the effect was that!).
I built my first version without these two small capacitors and despite all the work, once put the whole system has become more stable and it was easy to adjust the output offset REALLY close to zero. (before ranged from 0 to 40mV slowly varying, and now fixed and stable at about 2mv for channel).
With regard to the transistors, I use the configuration with the 2sk246-2sj103 and-bc550 BC560. For bias currents of 600mA on the transistors (I use TIP2955-TIP3055), the resistors are set to about 330 ohms.
Perhaps with the 2SK170 / J74 these values will vary, but I can not tell because I've never tried, (although I must admit that I'd like
). kind regards