Pictures of your diy Pass amplifier

...sorry...i hope it is no secret...

it looks very similar to yours ]

Yep that's the one, there are different sellers on ebay and aliexpress.
I bought from ebay. Only 126 euro a piece. but with 60 euro shipping.
When the chassis arrived I had to pay an additional 65 Euro taxes :mad:
So almost 250 Euros for this chassis.

It's a very good looking chassis, but quite a lot more than the equivalent modushop chassis. it looks so much better though...
 
...sorry...i hope it is no secret...

it looks very similar to yours ]

Yep that's the one, there are different sellers on ebay and aliexpress.
I bought from ebay. Only 126 euro a piece. but with 60 euro shipping.
When the chassis arrived I had to pay an additional 65 Euro taxes :mad:
So almost 250 Euros for this chassis.

Sorry for you Walter...but i know...... i paid for my caps delivery (3xSMPS and some audio caps) 35 euro extra tax fee ...so i know the tax fee is a horror.:mad:
 
A go at BA-3b + BA2 (nicknamed Overkill)

I started already in 2012 doing some calculations, drawing the pcbs and ordered the Toshiba FETs and heatsinks. However the build has stood still for most of the time due to other activities since then.
Late 2016 i started again with renewed enthusiasm and got to listen to the sweet sounds of this combo the first time in beginning of June 2017. I have only adjusted the gain in the BA-3b after that. Added a switch last week to have a low and high setting, high is now at about 33dB. Did not measure low but it is a lot lower.

The two BA-3b shares a box with the volume pot, a 4 gang motorized ALPS RK27, remote control card (cheap ebay thingie), relay card for inputs (2rca, 1 xlr, 1 phono) and a Salas simplistic riia. In the box under is the powersupply for the previously mentioned equipment. There are 6pcs simplistic Salas shunt regulators v1.2R packed into the box. 2x +30V, 2x-30V for the BA-3b, 2x +24V for the riia and just a rectifier and some capacitors for the controlboard. There is also a slowstart included for the two transformers. The boxes are from Modushop with 10mm front panel and sheet metal lid and bottom. Power supply box has heatsinks along the sides for the shunts and upper box is just plain sheetmetal.

The BA2s weigh in at 59.5kg each with 22kg of heatsinking, 10mm aluminium lid, mid platform and bottom and a sturdy frame of 20mm solid aluminium. Everything tapped and bolted together with 6mm screws. Three sides are made of plexiglass to show off the inside. Everything is on wheels so it is easy to move around when necessary.
Transformers are 2x21V 2000VA from toroidy.pl, Epcos 40V 100000uF capacitors in a CRC configuration giving 27V rails. 12xIRF240 and 12xIRFP9240 per monoblock biased at 600mA a piece.
Temperature on mosfets are around 60 degrees celsius. Slowstart is included, limited to 6A now if I remember correctly.

Finish is still open, would be fun to anodize the aluminium parts some time.


Hope I got this in the right thread this time :)
 

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Thanks!

I was first thinking about real glass but it was kind of expensive so I went for the acrylic.

Air flow inside the box is very limited, there is a small gap between the top and bottom and the sinks/acrylic but I do not think it does much for the airflow. during the build I was thinking that I can cut some holes in the bottom plate and increase the gap a little on top in case the temperature rises too high to get some airflow.