It seems to be 3RU 400 deep chassis. Old DIY Store was 300 deep.
https://diyaudiostore.com/products/universal-psu
This is the new 2025 3U Deluxe. All the new 2025 ones are 400 deep and the overall quality is better also.
Very nice! Saw the big package diodes on the psu pcb and assumed it was a fancy regulated PSU. Build looks great.
I will probably move the Toroid to the back and the PSU to the front for the heck of it anyway and see what happens once I finish with the Honey Badger I’m starting this weekend.Looks neat.
Consider swapping the toroid and PS PCB... that will vastly reduce the mains AC wiring loom, and will shorten the DC cabling length as well.
The stand-offs are very cute... but the mains wiring loom, if left long, should definitely be placed as close to the metal bottom plate as possible.... the reduction in noise could be as high as 10dB... easily visible if you look for it/measure it.
If you get the 400 mm deep version (all the new Deluxe 2U, 3U, 4U or 5U are 400mm deep) it is the same floor space as the big 5U case. I used 3U 400mm deep chassis for F5m, dual mono two transformers, two power supply boards, plenty of room and dead silent. Height was plenty, don't know about 2U, check transformer height.
Russellc
You can use a 2u for dual mono with a pair of 200va, but there won’t be enough clearance for the shields. Also will need to keep the bias at 1.1amps or else it will get too hot.
The 3U with 400mm deep, has more heatsink than the old 4U 300 version. Mine gets toasty, but can keep hands on it, no problem. Like original F5, it is DEAD SILENT.Thanks! And the 3u 400mm chassis is perfect for this amp if you want to bias it to 1.4a. At 72F room temp, the heat sinks are at 49-50C.
, just like you said. When youroving things around, convert to dual mono.
Russellc
I was Leary of 3U, but I believe it was 6l6 who pointed out the heatsink advantage over old 4U 300 deep. Since I had built both M2 and AlephJ in those, I had modushop custom make me a 3U 400mm "Deluxe" chassis. Within 2 days of delivery, store had new 400 mm deep deluxe versions! No biggie.You can use a 2u for dual mono with a pair of 200va, but there won’t be enough clearance for the shields. Also will need to keep the bias at 1.1amps or else it will get too hot.
Plenty of sink and I like the deep and low look. I've got assembled extra AlephJ and M2 boards I would like to build into the low and deep look
Also, you can now select custom "PASS DIY" face plate. Other face plates will be available later.
Hi all
Any suggestions for a SPST round shank switch for power that will fit the deluxe chassis 10mm front plate and be long enough to have enough threads to tighten securely
Cheers
Jody
Any suggestions for a SPST round shank switch for power that will fit the deluxe chassis 10mm front plate and be long enough to have enough threads to tighten securely
Cheers
Jody
Yeah that checks out… things happen when you are lazy and forget to read the announcements.If you get the 400 mm deep version (all the new Deluxe 2U, 3U, 4U or 5U are 400mm deep) it is the same floor space as the big 5U case.
It helps that there’s a great community here to reiterate info for dummies like me.

If you use a soft start board (such as H9KPXG) then a DC rated switch works. Many options at Bezos bookstore for that. If you want an AC rated switch, there are still possible options, just not nearly as many, and you will want to be sure it's truly rated for 120VAC (in US) at an appropriate amp rating. I've only used DC switches, so I can't vouch for AC options.suggestions for a SPST round shank switch for power that will fit the deluxe chassis 10mm front plate
For clarity, it's not the 'soft start' per se in the H9XPXG that allows the use of a (relatively low voltage rated) "DC" switch. 🙂 Folks interested in that circuit can review Mark's incredible application notes. The block diagram is wonderful.If you use a soft start board (such as H9KPXG) then a DC rated switch works.
I say this not for 'correction', but to alert others that may interpret it to mean that using another type of soft start would allow them to use the commonly seen 'low-voltage' anti-vandal switches sold for a few dollars on various platforms. Using that type of switch with (as an example) simple thermistor-type "soft starts" may result in an unsafe project at worst, or one that will cease to operate after a random number of on-off cycles at best.
I'm the guy that custom ordered one from modushop, next day store has it, yes in 400mm deep!Yeah that checks out… things happen when you are lazy and forget to read the announcements.
It helps that there’s a great community here to reiterate info for dummies like me.
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I've ordered a few from modushop while store has been out. Surprisingly quick, no longer than from store....but I wanted special 3U, 400mm deep....oh well, all's good in the end!
Russellc
well, ook, what I'm preaching all these years - Modushop 4U/400 is Swiss Knife product for our needs
just right chunk of Al, just right space inside

just right chunk of Al, just right space inside

Good correction. My choice of the term soft start was a dodohead poor choice. I never learn my lesson to just have patience and let the experts respond. At least when I do chime in, I always appreciate that my oogups are quickly clarified to help avoid confusion. Thank you!Using that type of switch with (as an example) simple thermistor-type "soft starts"
Luckily, anyone who looks up "H9KPXG" from @birdbox 's post #2,873, will discover the full and complete name is: Low voltage On-Off switch drives AC mains relay \ includes soft start .. H9KPXG
That single board allows for a 5 volt, 0.01 ampere on/off switch (momentary or toggle) , AND also happens to include soft start .
That single board allows for a 5 volt, 0.01 ampere on/off switch (momentary or toggle) , AND also happens to include soft start .
Still haven’t learned my lesson on proper size of cable, tend to be over generous with lenght. Making sure I have enough, which I knew I did. Anyways, this one should be singing very soon, fingers crossed.
Just sharing… not porn per se but some modest foreplay!

Have a great week!
Best,
Jose
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