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A few Super Black units just wrapped. Two are spoken for, and one is available for now.

Custom job. Direct clone of the original Marshall Bluesbreaker pedal.

Bit more of the same with new clothes. Made a few Klon-circuit custom drives in all-white.






And this one's a little bench tool I whipped up for testing tube preamp circuits. Switchmode power supply that takes a readily available 9V source and outputs 100 - 285VDC.

Dr Tony Balls wrote: Wed Oct 06, 2021 9:41 am Bit more of the same with new clothes. Made a few Klon-circuit custom drives in all-white.

Ooh, what do those go for?

losthighway wrote: Wed Oct 06, 2021 8:02 pm

Dr Tony Balls wrote: Wed Oct 06, 2021 9:41 am Bit more of the same with new clothes. Made a few Klon-circuit custom drives in all-white.

Ooh, what do those go for?

$200 post-paid in the US.

Going over it in my head I initially thought building in a rack could be challenging, but then thought maybe it wouldnt be so bad. The two roadblocks in my mind would be 1) heat, and 2) physical layout.

Heat is a concern, but could be easily solved with the integration of a little computer fan. Probably not a big deal.

Normally for the layout you've got a metal chassis with tubes and transformers that stick out the top or bottom. All that stuff is protected by a wooden head cab. Trying to put everything in one box is problematic because of heat and because how do you actually mount the tubes? They are meant to use both sides of a surface such as the inside and outside of a chassis. Some quick googling and I found pics of a Mesa thing and it made me think that the solution would just involve rack space covers. Build an amp in a standard rack box (1U maybe? if not 2U) where the tubes and transformers protrude out the top, and then include some perforated 2U rack covers to be installed in the spaces above the amp for ventillation. Kinda like this but perforated:

I think you could use 1U 19" rack and flip it upside down so it is serviceable from the bottom side, kind of like the enclosures you use for your amps. then get a 3 or 4 U front panel made that fits the mounting holes of the 1 U rack.

I would think upright would be ideal orientation, so your cathode heaters won't be slowly cooking your passives inside the chassis.

There are a number of manufacturers of rack-mount accessories that provide slotted and perf grilles in various RU sizes for passive cooling. There are also some active solutions, but using low-noise computer fans as well as brushless centrifugal blowers (that can compress the size to 1 RU) that will provide anywhere from 25-50 or more CFM cooling. Middle Atlantic/LegrandAV and Lowell are two of my go-to's for AV, but there's lower cost alternatives out there.

If you are intending this to mount with other equipment, then a top-panel over the tubes/xfmrs is a must, with active cooling maintaining a front-to-rear airflow within the rack, just like most current SMPS/Class-D commercial amplifiers .

I think Hammond makes a bunch designed to be racked.

Got to really crank up for the first time since the pandemic started and my Balls Custom Drive sounded sick.