Hi
Some time ago I started thinking about improving my Le monstre. At the same time I was convinced of the superiority of SMD tantalum resistors in audio and I decided to make a complete tantalum version including my regulators which are essentially improved Walt Jung superregulators.
Due to obligations at work, I'm quite late with the plan, so for now I've made new PCBs for the amplifier and the rectifier itself, the regulator PCBs have been made but the regulators haven't been finished or tested yet (except for the positive one). I also have to make some modifications in the box itself due to the different placement of the transformer.
So far, there is still a lot of work to do. To begin with, here are some pictures of how it looks for now.
Some time ago I started thinking about improving my Le monstre. At the same time I was convinced of the superiority of SMD tantalum resistors in audio and I decided to make a complete tantalum version including my regulators which are essentially improved Walt Jung superregulators.
Due to obligations at work, I'm quite late with the plan, so for now I've made new PCBs for the amplifier and the rectifier itself, the regulator PCBs have been made but the regulators haven't been finished or tested yet (except for the positive one). I also have to make some modifications in the box itself due to the different placement of the transformer.
So far, there is still a lot of work to do. To begin with, here are some pictures of how it looks for now.
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Here's some news, last week I managed to put together the first negative regulator. I did some quick tests just to make sure it wasn't oscillating or having any other problems and so far everything seems fine. This week I'll test it with a load and then I'll start finishing the remaining positive and negative regulators.
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Beautiful! Self etched I think? I am building a Le Monstre myself, curious if I will again appreciate it.
Yes ,self etched, I have perfected the technique without photo processing, I directly transfer the print to the PCB and into acid.
I love 100% DIY 🙂
I love 100% DIY 🙂
This is the second one for me, but in a new guise, and I'm just as interested as you are, but I'm convinced that this one will be much better.
This will not going to work... You would like to have factory ordered, 6 layer, colored and overmarked PCBs...
It is not "clean" and "pro"...
😎
What is there against "clean", "pro" and factory ordered? It is just choice. Whether it is self etched, JLCPCB, DIY or ready made: in the end it is about the level of execution and final result. Just think of putting much time & effort in 100% DIY and not a good result or 100% ready made and excellent result. Or a beautiful built ready made device but an ugly DIY device performing better. Which device would you listen to?
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I like it, looks well executed, you have mentioned those regulators before, i definitely would like to try your version.
As to home etching, i see absolutely no problem.
Perhaps you will reveal more details on parts
As to home etching, i see absolutely no problem.
Perhaps you will reveal more details on parts
Hi Jean-Paul,
I just want to make a joke 🙂 about fashion on forum about PCB design...
.
I like this hand made PCBs a lot!
Especially because they are made without photo transfer...
Excellent...
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Looking forward to read abut build and listening impressions from this legendary amp.
2SK170BL/2SJ74BL , 2SC3324/2SA1312 in a cascade, 2SC1940/2SA915 drivers, 2SC3284/2SA1303 output
The picture shows the regulators for one channel, positive and negative, the only TH components are three electrolytes, two 100uF/25V UKZ at the input of the op amp and one 820uF/35V FK for decoupling . Small PCBs with green leds are low-noise references from Walt Jung. All resistors are tantalum SMD as in the amplifiers, and each regulator has 4 depletion mosfets, 9 bipolar transistors and an op amp, which in this case is an OPA828.
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Hi
all these cascode drivers output are very close to original specs.....
did you use bypass resistor for 2SK170BL/2SJ74BL for lower idss?
@Nikos I did the same as Hiraga, listened and compared between several types, the choice fell on these in the end.
I did not add the bypass resistor for 2SK170BL/2SJ74BL for lower idss because the resistors in the output are reduced to 0.5ohm so that in LTspice there is a very small difference and only at higher power.
I did not add the bypass resistor for 2SK170BL/2SJ74BL for lower idss because the resistors in the output are reduced to 0.5ohm so that in LTspice there is a very small difference and only at higher power.
Any plans to publish schematic for the regs soon as well? Regulators are half the amp after all