OSCAR - Open Source Console for Analogue Recording

[pvision]

The Eurorack standard is 84 TE x 5.08 = 426.72mm = 16.8" so that is a good starting point for the width of a bucket

So long as the side panels or trims are >1.1" wide then a 19" panel will fit across the back of the bucket

I also like the idea that you could mount Eurorack synth modules into the same unit...

http://www.verotec.co.uk/web_book/03/03-%20Km6-1_16.pdf
http://www.doepfer.de/a100_man/a100m_e.htm


Nick Froome

 

[john12ax7]

A 2" channel adds up quick when doing many channels. It's good if using big pots and switches, but wastes space imo when using 9mm pots.

CAPI has a nice solution using a bracket that mounts into the buckets. A similar approach using interchangeable brackets at 1.5", 2" etc centers would add versatility.

 

[ruffrecords]

A 2" channel adds up quick when doing many channels. It's good if using big pots and switches, but wastes space imo when using 9mm pots.

The trouble with 9mm pots is it encourages you to place controls too close together. Then you need a tiny knob and tiny legend and the fingers of a pixie to operate them.

Cheers

Ian

 

[Rocinante]

Take a look at this:

http://www.schertler.com/en_US/arthur

I suppose none of us should be surprised.

 

[ruffrecords]

I know you keep being drawn back to the 500 format and I can understand why. However, as you said yourself, the mechanics of this project is key. The problem with the 500 series is there is no mass produced , available everywhere, low cost  metalwork for making the buckets. I know because I spent a lot of time trying to find it for the EZTubeMixer project.  I f I had found it then the EZTube Mixer project would be 500 compatible. That's why I ended up using Eurorack sub-racks. The components are available worldwide from many manufacturers. The system uses tapped strips in extrusions to attach modules. The strips have taps on 0.2 inch centres which means you cannot make 1.5 inch 500 series compatible modules. However, you could make 1.4 inch wide modules. exactly 12 of which would fit in a rack.

I am just wondering if there is a smart way to use this system but make 1.5 inch modules. If each module had two alternative top and bottom pairs of fixing holes, for example 0.9 inches apart horizontally,  then there would always be one pair that would mate with the tapped strip. Just a thought.

Cheers

Ian

 

[pvision]

I have had the tapped strips in extrusions in mind from the beginning. If a standard Eurorack is 16.8" then extrusions of that length must be easily available. If you standardise on those, constructing a bucket might only require pre-drilled side cheeks to complete

My thought on catering for the differing pitches of the mounting holes (which I imagine is 5.08 mm), 1.5" modules and 50.8mm (2" equivalent as 10 TE) modules is easy: use a slot on each front panel, rather than a hole

The attraction of the 500 Series is that it's a standard. I imagine the main reason for having a standard panel width is so that modules mate predictably with the edge connectors

I have been looking at an Audient ASP 8024 recently. It has 12-channel buckets which are near-as-dammit 19" wide. It seems to be wired with ribbon cable and I have a strong suspicion there are no channel edge connectors (each bucket is a 1-board setup)

So why have edge connectors? Why not ribbon cables and sockets on the boards? Eurorack synth modules don't have edge connectors, they have flying leads to connect to a power busbar and in/out connections on the front panel

Why not adopt that approach? A power busbar and an audio ribbon cable - or just a ribbon cable. That way the pitch of each channel / module can be anything you like

An attraction of a 1.5" pitch is that it will align vertically with 500-Series modules. It's not relevant for everyone

Nick Froome

 

[pvision]

I just dredged from my memory that the extrusion & tapped insert is called ISEP rail

http://www.srs-products.co.uk/isep.htm

I don't know if this is the same as the Eurocard standard in every detail. But SRS also carries Eurorack standard parts

Here's the Eurorack front mounting rail standard

http://www.srs-products.co.uk/PDF/extrusions/65605X.pdf

Nick Froome

 

[zamproject]

ISEP is fine !!! but it's an old German (Telecom/Deutsch post?) standard...
For audio I only saw them used by old Midas and 60' 70' Studer, like my beloved studer 289
By the time I think it was a high standard, gold plated, spring contact, but the max is 33 pin (fit in 3U i think), only single raw

Euro is a great industry standard, and the  first time I saw the Ian tube modular desk design, I say myself, FINALY !!! someone that use a nice standard, IMO way better than 500... mechanical and modularity speaking

with DIN 41612 connector you can go up to 96 pin per card, card have rail guide, and you can have sub enclosure with KM6  system

I don't think anything can beat this industry standard used since decade...

That way the pitch of each channel / module can be anything you like

An attraction of a 1.5" pitch is that it will align vertically with 500-Series modules. It's not relevant for everyone

And yes, wild is modular too you can also find rail longer than 84HP 19' (I saw some 1 meter 190HP !)
Bus board can have 2HP pitch for connector, you solder where you need

Best
Zam

 

[ruffrecords]

I have had the tapped strips in extrusions in mind from the beginning. If a standard Eurorack is 16.8" then extrusions of that length must be easily available. If you standardise on those, constructing a bucket might only require pre-drilled side cheeks to complete.

In best Blue Peter tradition, here's one I made earlier. Shape designed in a 2D CAD package, dxf imported into Front Panel Designer where the mounting holes for the extrusions were added. File sent to Frank Rollen who made them. Note, although this is 8 modules wide, it is not 19 inches wide; it uses custom length extrusions 112HP wide. I later discovered that making your own custom length extrusions is not difficult. You can buy 1 metre lengths but the fixing holes are not tapped. Once again Frank Rollen came to my aid and sent me a video showing how easy it is to tap pre-drilled holes using a drill, a tap and the right lubricant.

Cheers

Ian

 

[abbey road d enfer]

I know you keep being drawn back to the 500 format and I can understand why. However, as you said yourself, the mechanics of this project is key. The problem with the 500 series is there is no mass produced , available everywhere, low cost  metalwork for making the buckets. I know because I spent a lot of time trying to find it for the EZTubeMixer project.  I f I had found it then the EZTube Mixer project would be 500 compatible. That's why I ended up using Eurorack sub-racks. The components are available worldwide from many manufacturers. The system uses tapped strips in extrusions to attach modules. The strips have taps on 0.2 inch centres which means you cannot make 1.5 inch 500 series compatible modules. However, you could make 1.4 inch wide modules. exactly 12 of which would fit in a rack.

I am just wondering if there is a smart way to use this system but make 1.5 inch modules. If each module had two alternative top and bottom pairs of fixing holes, for example 0.9 inches apart horizontally,  then there would always be one pair that would mate with the tapped strip. Just a thought.

Cheers

Ian

Ian, when I made mixers in a previous life, I used standard extrusions and chose a 40.64 mm pitch, which allowed me to make the modules out of standard L-shaped 40mm extrusion. I had the chassis made by a specialist company, and they had 3-hole tapped strips that were held in place with plastic rings, which allowed them any spacing. My choice of 40.64 allowed me to use standard strips that were about 80cm long.
40mm width allows the use of 12mm pots, even 16mm that are easier to source.
40.64 pitch would allow the use of 1.5" modules with the simple addition of a gasket...

 

[ruffrecords]

I know you keep being drawn back to the 500 format and I can understand why. However, as you said yourself, the mechanics of this project is key. The problem with the 500 series is there is no mass produced , available everywhere, low cost  metalwork for making the buckets. I know because I spent a lot of time trying to find it for the EZTubeMixer project.  I f I had found it then the EZTube Mixer project would be 500 compatible. That's why I ended up using Eurorack sub-racks. The components are available worldwide from many manufacturers. The system uses tapped strips in extrusions to attach modules. The strips have taps on 0.2 inch centres which means you cannot make 1.5 inch 500 series compatible modules. However, you could make 1.4 inch wide modules. exactly 12 of which would fit in a rack.

I am just wondering if there is a smart way to use this system but make 1.5 inch modules. If each module had two alternative top and bottom pairs of fixing holes, for example 0.9 inches apart horizontally,  then there would always be one pair that would mate with the tapped strip. Just a thought.

Cheers

Ian

Ian, when I made mixers in a previous life, I used standard extrusions and chose a 40.64 mm pitch, which allowed me to make the modules out of standard L-shaped 40mm extrusion. I had the chassis made by a specialist company, and they had 3-hole tapped strips that were held in place with plastic rings, which allowed them any spacing. My choice of 40.64 allowed me to use standard strips that were about 80cm long.
40mm width allows the use of 12mm pots, even 16mm that are easier to source.
40.64 pitch would allow the use of 1.5" modules with the simple addition of a gasket...

There is a lot to be said for using standard parts wherever possible if for no other reason than continuity of supply and reasonable cost. I have seen plenty of professional modules that use extrusions top and bottom - Calrec comes to mind - so this can be a powerful technique. The whole question of how to construct a module in a standard but flexible manner is extremely difficult. A key objective must be to ensure the front panel controls and the PCB they are attached to are not part of the structural integrity of the modules. Easy to say, much harder to do. Attached is a pic of a 7HP (1.4" or 35mm) module I am working on right now. The only special part is the 1mm steel sides plate I had cut to size. Everything else is standard. At the front from left to tight we have 25mm M2.5 screw, 1mm steel, 3mm spacer, 1,6mm PCB, 7.1mm Schroff standard front panel fixing diecasting, 20mm spacer, 1mm steel sheet and M2.5 screw. The space between the top surface of the PCB and the bottom surface of the right hand steel sheet is 27mm, so as you say, 16mm pots can be accommodated.

Cheers

Ian

 

[pvision]

Ian

You are designing your mixer from the inside out, whereas I am designing it from the outside in. That's because I haven't built a mixer before and you have...

Your concept of standard parts extends to nuts, bolts standoffs & etc. That makes huge amount of sense as "5-minute jobs" like cutting down screws, etc, take up a disproportionate amount of time. I know from working on cars that ten, 10-minute jobs will take all day!

One tiny detail I thought of: when cutting aluminium by hand it's really easy to end up with angles ≠ 90 degrees or some doming of the end of a part after filing it "flat". So if the bucket could be made with pre-cut extrusions it would be closer to square and a lot more rigid. The addition of a lower panel that sits inside the side panels would help as well

Nick Froome

 

[abbey road d enfer]

One tiny detail I thought of: when cutting aluminium by hand it's really easy to end up with angles ≠ 90 degrees or some doming of the end of a part after filing it "flat". So if the bucket could be made with pre-cut extrusions it would be closer to square and a lot more rigid.

I think you need to accept the fact that you need some tools; a miter saw is a blessing when working with extrusions. On ecan be had for about $100, new. It's noisy and generates a lot of filings though; you can't just use it in teh kitchen...

 

[john12ax7]

The eurorack seems nice but aren't they expensive, like $250 or $300 for a 3U?

Another option would be turning a normal rack panel vertical and using 1.75" spacing.

 

[ruffrecords]

The eurorack seems nice but aren't they expensive, like $250 or $300 for a 3U?

Another option would be turning a normal rack panel vertical and using 1.75" spacing.

A basic 3U sub-rack is less than $50:

http://uk.farnell.com/schroff/24563-191/subrack-3u-175mm-84hp/dp/1455794

Cheers

Ian

 

[john12ax7]

The eurorack seems nice but aren't they expensive, like $250 or $300 for a 3U?

Another option would be turning a normal rack panel vertical and using 1.75" spacing.

A basic 3U sub-rack is less than $50:

http://uk.farnell.com/schroff/24563-191/subrack-3u-175mm-84hp/dp/1455794

Cheers

Ian

Seems I've been looking in the wrong places.

Thanks Ian

 

[ruffrecords]

A basic 3U sub-rack is less than $50:

http://uk.farnell.com/schroff/24563-191/subrack-3u-175mm-84hp/dp/1455794

Cheers

Ian

Seems I've been looking in the wrong places.

Thanks Ian

There are umpteen variations and  if you buy the tough versions designed to be used on railway trains plus the EMC package and screens all built into a nice desktop case then the price does rocket into the hundreds. The basic one is very basic; it's just four extrusions and two side plates but that is all you need really. At one point I was planning to build a 1 metre wide console similar to Holger's. I bought all the extrusions and standard side plates for it for under £200.

Cheers

Ian

 

[anjing]

It took me a while to find 1000mm rails....the only ones i found that were affordable and would ship to north america is GieTech
http://www.gie-tec.com/housings---profiles/aluminum-housing-profiles/index.html
Mounting profile 1 and 2.

 

[Dylan W]

I've spent some time thinking about this and one solution that I don't think has been mentioned is using aluminum extrusion with slidable nut plates, so the modules can be fixed on whatever center spacing you like.

http://microrax.com will cut to order and they're quite inexpensive. You can build just about anything out of them, taking into account the load-bearing limitations of the extrusion thickness. Thoughts?

 

[abbey road d enfer]

I've spent some time thinking about this and one solution that I don't think has been mentioned is using aluminum extrusion with slidable nut plates, so the modules can be fixed on whatever center spacing you like.

I mentioned that in post #29. It gives a lot of flexibilty for specific modules like spacers, 1.5 wide or any random width.