Jean Hiraga Super 30 - The Beginning

Lionx

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This is the build log of a Jean Hiraga 30W class A amp which is my first attempt to make DIY product without the normal characteristics of a DIY Build. The word DIY usually associates with low cost, functional design with less importance given to aesthetics but I wanted to challenge myself to a design which can compete with professional units in terms of build quality.

I ventured into audio DIY very recently (2018) and was looking for a perfect amp for myself, that was the time I got introduced to Hifivision and stumbled upon this particular thread of Sadik’s. Sadik's JH30.
As most of you know, he is a master craftsman and I always envied his engineering skills. I was a first-time builder neither equipped for such extensive build but didn’t hesitate to grab couple of his pcbs when he listed them for sale in the forum. It was designed by Aniket whos is very well known in DIY space for his DD amps, I didn't have any doubt on the build quality and design of these boards.

IMG_20180423_234448.jpg

The real challenge was that I had no clue where to start but gained confidence after reading about various JH builds around the world and started ordering parts from RS components. All these were happening in 2019 and there were many others discussing about group building JH in various WhatsApp groups. A friend has asked my help in building one for him during one such casual talk which I tried to discourage as I was not confident myself as a builder. But he was very persistent and had more confidence on me, I didn’t have any choice other than to accept the challenge. We had discussed an estimate and delivery deadline of January 2021, with this I started planning activities backwards (I am in to IT and the project management experience really came handy here ).

Below were my to-do lists,

~~ Populate amp boards with high quality components
I believe in quality and was not ready to compromise on component quality, which includes audio grade caps (ELNA, Denon, Wima), Precision Resistors (Vishay Dale) and original active devices from ON Semi.

IMG-20201223-WA0022.jpg

~~Heatsinks
As with any of the Class A amps, this is the most significant component which defines how ‘cool’ is your amp and how “heavy” it is. Usual trend is to have a 250-300mm heatsink for each channel with both transistors mounted on it. I decided to take it a bit further and ordered 4, one for each transistors, each of these weighting 2KGs and the amp already grown to 8Kgs . The below picture is after a failed attempt to anodize it in gold color, the final finish is different.

IMG-20201223-WA0008.jpg

~~Transformer
The original design uses a 500VA and I decided to go with the same. I went with R-Core as it is supposed to have the least flux leakage and the cost difference was not that much compared to torroid. The spec is 24V – 0 – 24V and 12V – 0, 512VA, weighs about 7kg.

The cassette is to get a reference for understanding the size.
IMG-20201223-WA0012.jpg

~~Capacitor bank
This is the most dreaded part in a JH build as the design is very sensitive to power supply noises. The original design uses about 1F of capacitance to smoothens the DC which uses massive capacitors and eventually adds to the cost. I didn’t want to go with those beer can capacitors mainly due to cost and lack of availability hence opt for 2 separate boards each comprising of 16 4700uf capacitors.

IMG-20201223-WA0015.jpg

~~Chassis Design
I started with a clean state and my design evolved around the heatsinks, like how to make them look symmetric, what is the best placement for effective heat dissipation etc. Since I am illiterate with CAD and similar software; my only option was the same old pencil and paper. It took me almost 3-4 months to get the complete design after numerus iterations evaluating pros and cons. I decided to build it with 8mm aluminum plates for all sides which will also act as heatsinks.
IMG-20201223-WA0006.jpg

8mm Plates
IMG-20201223-WA0021.jpg
 
Continuation....
Finding the right guy for each job was the most difficult part in these kind of builds as most of the vendors are not interested and ready to take up one off project. I had to run around quite a lot in Bangalore checking out vendors listed in JustDial and similar sites. I will be listing down all these at the end so that it will be much easier for guys like me in future.

Since my sketch has so many design elements, CAD design became very important and that took me weeks to get the right person, the corona lockdown was not helping either. Had to have multiple sessions with the CAD guy to tweak the design and after 3 weeks of constant follow ups I received milled panels. It was an ecstatic moment seeing the design which was there only in your brain right in front of you.

IMG_20201014_124937.jpg
IMG_20201014_124931.jpg
IMG_20201014_125005.jpg
IMG_20201017_183112.jpg

I had ordered all the necessary parts in the meantime and was ready to kick-start test assembling the chassis. I followed the automobile way of wiring and created separate wiring looms for each boards terminated with lugs and spades. The power wires are 2.5sqmm and 1.5sqmm, the input signal wires are shielded Canare microphone cables. Learnt the braiding technique from YouTube ;).
IMG-20201223-WA0002.jpg

The PCBS are arranged for marking the mount holes, all the 3mm threads are manually done at home using hand drill and tapping kit. The transformer is mounted using M5 bolts like all the chassis panels.
IMG_20201019_203346.jpg

The small board is a soft start to avoid current surge.
IMG_20201019_203319.jpg

I had to go for double layer arrangement as the chassis was compact and most of the space was eaten by transformer itself. The wiring layout has been finalized after multiple trials to avoid any ground loop and hum.
IMG-20201223-WA0009.jpg

PCBs are mounted on Aluminum square tube cut into half.
IMG_20201020_192006.jpg

Test assembled,
IMG-20201223-WA0016.jpg

I ran it like this for couple of weeks to understand the heating effect and bias adjustment. Temperature was hovering around 53 degree after 2 hours of operation.
IMG-20201223-WA0003.jpg
IMG-20201026-WA0045.jpg
 
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Once I was satisfied with the performance, the amp has been dismantled again for final finish. Each panels were sanded off and drill holes were counter sunk for a sleek finish. I have decided to go with Black and Copper theme which usually gel very well and looks premium. I had my logo designed and cut using waterjet on 1mm brass sheet and also provisioned the space on the top and front panels.
IMG-20200601-WA0032.jpg

I went for hard anodizing which is gives more durability and also scratch proof compared for normal finish. The panels were buffed as well post anodizing to give a brushed finish.
IMG-20201104-WA0026.jpg

The name has been laser printed on front plate, this was an experiment but it turned out to be really nice.
IMG-20201104-WA0010.jpg

IMG-20201104-WA0013.jpg
IMG-20201104-WA0024.jpg

I went a bit overboard with this build; wanted matching copper bolts for a uniform look. The hurdle was that off-the-shelf copper bolts were too flashy and spoils the entire theme; I started my research on the DIY route and there were many videos available in YouTube on this subject.

Nickel plating the bolts as its the first step of the process and then repeat the same process for copper.
IMG-20201107-WA0025.jpg

The results were more than satisfactory, I wanted this vintage copper look.
IMG-20201108-WA0027.jpg

The corner stand mounts are milled out of 1” copper tube and the spikes are made out of steel. The design is such that the spikes are threaded to the corner rods so that the amplifier can be aligned even on an uneven surface.
IMG-20201223-WA0001.jpg

The rods are polished and coated with epoxy to retain the shine, even the spikes are epoxy coated for keeping them rust free.
IMG-20201223-WA0000.jpg
 
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Started final assembly once all these individual design elements are in place.
int.jpeg

Clean bottom plate.
IMG-20201120-WA0027.jpg

The internals are fixed and wiring sorted. I have used star grounding method to remove amplifier hum.
internal.jpg

Note the slots on front and rear plates, the top plate will flush mount on those and same with the bottom plate, there wont be any seam visible in the elevation. The front panel is insulated from the heatsinks using thermal insulator hence it wont get hot. Also the bolts are thread locked with gasket sealant even the capacitors and other tall components are sealed using hot glue to make it safe for transportation.

As promised, below are my sources,
1. Electronic Components - Element 14, RS components
2. The AudioCrafts - VU Meters, Protection boards, Connectors
3. ProjectPoint - Wires, Wire lugs
4. CNC - Sainath Industries, Begur road, Bangalore
5. Anodizing - Anodik Solutions
6. Laster printing - AdLife, HSR Layout, Bangalore
 
Time for the unveil :)
PicsArt_12-18-08.29.11.jpg

The cat eyes,
cat.jpg
The Neutrik Powercon connectors,
DSC_5192.jpg

With 2.5sqmmx3 custom power cable,
power.jpg

Rhodium RCAs,
RCA.jpg

Binding Posts
Binding.jpg

Rear panel
rear.jpg

You may see the Logos are placed with Epoxy and has a shine which enhance the contrast.
full.jpg

The spikes has a shine due to epoxy but retains the natural look.
DSC_5234.jpg

The top plate logo has a subtle background color.
DSC_5172.jpg

That's how I look when playing.
DSC_5171.jpg

This is designed to be kept on the floor for smooth air circulation, the amp gets only warm (below 40) now even after hours of operation. The massive heatsinks and black anodizing must be helping, you wont feel that its a Class A in operation. There is no need to explicitly mention how the amp sounds as JH design is well known for the warm sound and butter smooth mids. It has a real nice control on the low notes and has plenty of power to drive most of the speaker units, we had paired it with Tannoys towers and the result was mesmerizing.

The amp has been delivered last week, a month earlier than the target date and well within the budget.

The signoff pic,
final.jpg


Thanks for viewing, please let the comments flows.
 

Attachments

  • DSC_5175.jpg
    1,019.4 KB · Views: 55
Time for the unveil :)
View attachment 53247

The cat eyes,
View attachment 53262
The Neutrik Powercon connectors,
View attachment 53249

With 2.5sqmmx3 custom power cable,
View attachment 53250

Rhodium RCAs,
View attachment 53252

Binding Posts
View attachment 53253

Rear panel
View attachment 53254

You may see the Logos are placed with Epoxy and has a shine which enhance the contrast.
View attachment 53255

The spikes has a shine due to epoxy but retains the natural look.
View attachment 53256

The top plate logo has a subtle background color.
View attachment 53257

That's how I look when playing.
View attachment 53258

This is designed to be kept on the floor for smooth air circulation, the amp gets only warm (below 40) now even after hours of operation. The massive heatsinks and black anodizing must be helping, you wont feel that its a Class A in operation. There is no need to explicitly mention how the amp sounds as JH design is well known for the warm sound and butter smooth mids. It has a real nice control on the low notes and has plenty of power to drive most of the speaker units, we had paired it with Tannoys towers and the result was mesmerizing.

The amp has been delivered last week, a month earlier than the target date and well within the budget.

The signoff pic,
View attachment 53260


Thanks for viewing, please let the comments flows.
Thanks for building an amazing JEAN HIRAHA SUPER 30 for me SUMITH...i love the sound and design tooo much...just cant pay off your efforts... it's just marvelous ❤️❤️
 
Wow that's one of the best builds on the forum. Really well presented and detailed.

Do try posting a sound demo. Also, could you monitor the power consumed by it in an hour or two of running?

MaSh
 
Wow that's one of the best builds on the forum. Really well presented and detailed.

Do try posting a sound demo. Also, could you monitor the power consumed by it in an hour or two of running?

MaSh
Its been delivered, the new owner is part of the forum. I will ask him to post one.

I didn't monitor the power consumption but the biasing is 1.35A and DC voltage is 33V.
 
Started final assembly once all these individual design elements are in place.
View attachment 53242

Clean bottom plate.
View attachment 53243

The internals are fixed and wiring sorted. I have used star grounding method to remove amplifier hum.
View attachment 53244

Note the slots on front and rear plates, the top plate will flush mount on those and same with the bottom plate, there wont be any seam visible in the elevation. The front panel is insulated from the heatsinks using thermal insulator hence it wont get hot. Also the bolts are thread locked with gasket sealant even the capacitors and other tall components are sealed using hot glue to make it safe for transportation.

As promised, below are my sources,
1. Electronic Components - Element 14, RS components
2. The AudioCrafts - VU Meters, Protection boards, Connectors
3. ProjectPoint - Wires, Wire lugs
4. CNC - Sainath Industries, Begur road, Bangalore
5. Anodizing - Anodik Solutions
6. Laster printing - AdLife, HSR Layout, Bangalore
Fantastic, lovely build!
 
Continuation....
Finding the right guy for each job was the most difficult part in these kind of builds as most of the vendors are not interested and ready to take up one off project. I had to run around quite a lot in Bangalore checking out vendors listed in JustDial and similar sites. I will be listing down all these at the end so that it will be much easier for guys like me in future.

Since my sketch has so many design elements, CAD design became very important and that took me weeks to get the right person, the corona lockdown was not helping either. Had to have multiple sessions with the CAD guy to tweak the design and after 3 weeks of constant follow ups I received milled panels. It was an ecstatic moment seeing the design which was there only in your brain right in front of you.

View attachment 53219
View attachment 53220
View attachment 53221
View attachment 53222

I had ordered all the necessary parts in the meantime and was ready to kick-start test assembling the chassis. I followed the automobile way of wiring and created separate wiring looms for each boards terminated with lugs and spades. The power wires are 2.5sqmm and 1.5sqmm, the input signal wires are shielded Canare microphone cables. Learnt the braiding technique from YouTube ;).
View attachment 53223

The PCBS are arranged for marking the mount holes, all the 3mm threads are manually done at home using hand drill and tapping kit. The transformer is mounted using M5 bolts like all the chassis panels.
View attachment 53224

The small board is a soft start to avoid current surge.
View attachment 53225

I had to go for double layer arrangement as the chassis was compact and most of the space was eaten by transformer itself. The wiring layout has been finalized after multiple trials to avoid any ground loop and hum.
View attachment 53226

PCBs are mounted on Aluminum square tube cut into half.
View attachment 53227

Test assembled,
View attachment 53229

I ran it like this for couple of weeks to understand the heating effect and bias adjustment. Temperature was hovering around 53 degree after 2 hours of operation.
View attachment 53230
View attachment 53231
Great work Sumith! so what you shared with me earlier was only a preview then... :)

...
 
Great work Sumith! so what you shared with me earlier was only a preview then... :)

...
Yes, the final design was still cooking in my mind then. As I said the the design was not frozen and I was adapting to the assembly challenges.
 
Purchase the Audiolab 6000A Integrated Amplifier at a special offer price.
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