///***///---Feeler LuNcH-Box 500 Series---\\\***\\\

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Hey audiox, any idea if you could incorporate this jumper idea?

Sounds great, but if you could open yours up to higher rails without needing to get over complicated, it would be awesome!!

-Tom
 
I opened the project CAD file again and I am doing some checking. Could someone who owns a real lunchbox measure following dimensions:
- spacing of modules in lunchbox (easiest to measure distance between centres of threaded holes of two nearest modules)
- distance between the two mounting holes in a front panel
- front plate dimensions of a real api module
(as accurate measurements as possible)
 
[quote author="TomWaterman"]I have an even better idea, why not make the internal power supply with BOTH a +/-16V rails AND +/-30V rails?

You could have a small jumper on the back plane that would set the voltage at the EDAC power pins for each module. That way it would be very easy to use existing 16v designs with higher spec'd DIY types/Neve etc.[/quote]
That strikes me as a good way to blow up a pricey 500-series module at some indeterminate point in the future, when you (or your assistant) are in a hurry and forget about the jumper.

FWIW, the 500ish rack I'm working on has a backplane with two sets of connectors, regular EDAC for vanilla 500 modules and separate connectors for custom modules. For the custom connector I'm thinking DIN-41612: cheap, reliable, standardized across multiple manufacturers, no pesky hard-to-DIY edge connectors and rated for high voltages (planning a dual-MILA in two 500-slots).

JDB.
 
Yeah well it is risky, if you don't pay attention.

But for DIY where we should be capable of not messing it up, I see the jumper solution as the cheapest and easiest way to get this to work. The rest require large multilayer backplances and deeper card depths/mechanicals...

I suppose you could just use a little IDC cable with the higher rails on it coming from the backplane, and on higher rail designs ignore pins 12-14 for the +/-16V rail and plug in the little ribbon with +/-30V on it. At least that spares the need for large connectors on backplanes etc.

SCA were supposed to be working on a rack with 500 series adapters that run on PCI connectors with higher rails etc.... looks like that will never come.

-Tom
 
[quote author="TomWaterman"]The rest require large multilayer backplances and deeper card depths/mechanicals...[/quote]
What makes you think that? My preliminary case/backplane layout with mixed EDAC/DIN41612-connectors is exactly as deep as a regular 500-series case. The DIN connector has a low enough profile that it can be used in conjunction with fully-closed 500 housings like Rochey's. The PCB is double-sided, but that's because I'm lazy and love ground planes and thus almost never do anything in less than 2 layers. Without the ground plane there's no reason the board can't be single sided.

Backplane PCBs are an issue in any case, as they can get flexed a lot in normal use. That's no good for traces and solder joints, so you'd want to go for a thicker board, which is disproportionally more expensive. I'm looking into fixing that by not having one big 10-connector backplane but five smaller 2-connector PCBs instead. The downside is that you need to do more wiring, on the upside you can have a hybrid case with for example 8 regular EDAC slots and a special doublewide module slot for, say, a stereo compressor.

JDB.
 
Yeah you're right I suppose. I was specifically thinking of a few people/companies I know working on similar ideas/solutions, one of which involved elaborate daughter/adapter cards and local regulators to enable 500 series operation and the other required large multi-pin backplane connectors to hugely update the feature set with things such as 8 aux/busses for mixing, digital I/O etc.

All of which require upto 4 layer backplanes with 40+ pins.

Your plan sounds good indeed, with an extra connector on the board. Have you got rear mounted XLRs and the two connectors on a 2-layer backplane?

If I understand you correctly, the only wiring needed would be linking power between mini-backplanes across the rear of the rack?

Sounds good.
-T
 
[quote author="TomWaterman"]Yeah you're right I suppose. I was specifically thinking of a few people/companies I know working on similar ideas/solutions, one of which involved elaborate daughter/adapter cards and local regulators to enable 500 series operation and the other required large multi-pin backplane connectors to hugely update the feature set with things such as 8 aux/busses for mixing, digital I/O etc.

All of which require upto 4 layer backplanes with 40+ pins.[/quote]
I can imagine. My own plans are much more pedestrian: power, XLR in, XLR out. While I am planning to build stereo compressors in this format, I intend to make those doublewide modules with no over-the-backplane link signals or the like. The only feature I would consider adding (to the expanded 41612-connector) would be a simple unbalanced send/return-insert for sidechains.

[quote author="TomWaterman"]Your plan sounds good indeed, with an extra connector on the board. Have you got rear mounted XLRs and the two connectors on a 2-layer backplane?[/quote]
Yes, after a fashion. The EDACs are PCB-mounted. Originally I wanted to use Neutrik PCB-mount XLRs, but a few prelim tests showed quite a bit of flex stress on their solder connections. The new plan is to have regular B-series panel mount XLRs with very short (~5mm) wires running through oversized PCB holes to solder tabs. The idea is that you mount the backplane to the rear panel with standoffs connected inline with the EDAC's mounting holes. I do have to work a bit more on the mechanical side, but those Neutrik B-series XLRs mount from the inside of the panel, so you can remove a (sub)backplane PCB without desoldering anything.

[quote author="TomWaterman"]If I understand you correctly, the only wiring needed would be linking power between mini-backplanes across the rear of the rack?[/quote]
Indeed. Another thing I'm looking into is giving each PCB its own local 317/337 regulator, which would be mounted to the inside of the rear panel right above the XLRs. The idea is that it's much easier from a heat management perspective to have five regulator pairs spread across the case each supplying 260mA max than one big reg pair delivering up to 1.3A in a fully loaded rack. 317s cost nothing anyway, and this scheme won't hurt inter-module supply immunity either.

JDB.
[What you mentioned about adapters did get me thinking, though. For my own personal use I expect maybe 20% true-500 EDAC vs 80% 41612, so it may make sense to just do the backplane boards in 41612 and have small adapters to translate between the two. This would give the 'native' 41612-designs some 10mm extra space, which wouldn't hurt, at a negligible increase in main case depth. Must ponder this some more.]
 
Are you planning on manufacturing in Europe? While $500 is a bit out of range for me.. perhaps we can make it cheaper in the US? At least Cheaper for he europeans... In either case, Red, let me know when this is good to go, and I can get a quote from a friend in Chicago. It couldn't hurt anyway.
 
Yeah Mitsos , very good idea!
Just let us know what would be the average price in US!

Everyone is welcome here to perform this lunchbox and to push it cheaper!!

We also need a PCB designer for the EDAC
--->>I mean a EDAC holder , for ten of them.
--->>And a lot of "male" to put in the edac (the goal is to lay a 9k in a 500 module for example.)See this :
http://www.groupdiy.com/index.php?t...er=asc&highlight=500+series+rack+idea&start=0
Scroll down to the 312 , see "end" connector.(Gar381 work)
 
Two things I still need :

-->>Are the guides for the cards necessary??(As i do not see any in original cases)

-->>Edac fixed?Correct??So:Do you prefer just a "hat" for the top and the bottom of the case???(This depends on the answer you'll gave concerning first question!)

Take care gonna shout :
PLEASE TELL ME IF I'M NOT CLEAR !!!!I'LL DO PLANS!!!!
ahahahahahahaha.... :green:
 
Hi Rednoise,

There is a problem with the file you linked. It has the address to your C drive.


Audiox: (from the file Rednoise sene me..not official API sheet)
500 series front panels are 5.25 x 1.5 inches
Mounting screw distance is 4.938 inches
I would guess spacing between module is 1.5 inches.. there is no space between them is there? Someone please confirm...

It's easiest if you see the sheet. I'd prefer if Rednoise sent it to you just cuz he got permission from the author.

Also, your mechanical parts cost 30 euros? This is materials only right? Not to build it, right? If you can send me drawings I can get a quote from my friend who does excellent work.

Exciting times...
 
[quote author="RedNoise"]Thx Natek !![/quote]

No problem! I cam across that on some other site the other day and thought it might be helpful for this project! I am also interested in figuring out some lunch-boxes, If this gets a good plan together and we can get them made in the US for cheaper i will be happy to get some quotes locally too! Thank YOU for working on this! :):thumb:

My best,
Nate
 
I read somewhere on a french site that in the 4 slots original api box , the psu was better than in the chinese one (6 & 11 slots)
Any comments on that??The guy said it works really better in his 4 slots...But he wants 300e (!!) :evil:
Maybe someone have original (vintage) psu schems?? :grin:
 

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