Compact desktop line mixer?

[darth fader]

Front Panel designer can export an entire panel as a dxf file but I think it can only import a panel outline which may explain the errors. I have never tried importing an entire panel in dxf format into front panel designer. I posted it as dxf mainly for the benefit of @darth fader who I suspect is not familiar with front panel designer but is with dxf

When it comes to the engraving of text and so on, I no longer specify engraving because it is expensive and limited. Instead I specify UV printing which I have found to be just as durable but a lot cheaper and you can easily do graphics if you want to. I don't know if Frank can do this yet.

I am having breakfast at the moment (it is 9am here) using a laptop so I don't have access to the fpd file. I will post it later today when I get over to the workshop.

By the way, the panel thickness I chose was 2.5mm and there are no corner radii - the panel is rectangular.

Cheers

Ian

Much appreciated Mr Ian! You are correct about not being familiar with front panel designer and I can load dxf files directly into "my" Proto Trak dpm rx3 milling machine here at work

 

[darth fader]

I just need to get a dxf file on to a thumb drive and into my machine, it's not networked. then do some simple conversational programing then I can run some parts. Really just as an exercise TBH.

 

[dmp]

The tepid response here (and the apparent lack of commercial products) might indicate there is little interest.

I can imagine a DIY building block system that could be used for OTB mixers, or a sub mixer for a synth rig. I even poked around at Mouser checking out prefab wiring solutions to connect front panel parts to a PCB(s).

I would be interested. I've wondered why there hasn't been more DIY projects along these lines.
I think a pseudo 500 series version of a project like this would be great (1.75" panel width, each channel an individual PCB) that could be built into a desk with 500 pres and modules. Wouldn't necessarily need to be limited to 3U high if more controls are needed.
A fader & balance pot, switches, and some aux buses. Cost would be low. Then each channel pcb could connect through bus wiring to a mix and bus output amplifiers in a separate enclosure.
I've wanted to build a module desk for some time and this would make it possible.

 

[kags]

Purple Audio released (now discontinued?) MFTwenty5 around 2017. I demoed a modular system and found it intriguing, but expensive with all rue options- around $7,000. It might still be made to order.

It is based on 500 racks, fader pack, meter module, and a 1-RU summing mixer. Expandable and modular.

Product page:
https://purpleaudio.com/products/mf-twenty-25/

Review from TapeOp
https://tapeop.com/reviews/gear/118/mftwenty5-modular-console/

 

[JohnRoberts]

FWIW, I've been noodling around in my brain on this concept. (After a 13" snowfall here in KS, I've been house-bound since last weekend. At my age, shoveling that much snow from my driveway is just asking for a heart attack...lol!)

The tepid response here (and the apparent lack of commercial products) might indicate there is little interest.

I can imagine a DIY building block system that could be used for OTB mixers, or a sub mixer for a synth rig. I even poked around at Mouser checking out prefab wiring solutions to connect front panel parts to a PCB(s).

shrug.....

Bri

FWIW back in the 80s I evaluated offering a modular mixer kit series through my kit company.

In hindsight I'm glad that I demurred.

JR

 

[darth fader]

I would be interested. I've wondered why there hasn't been more DIY projects along these lines.
I think a pseudo 500 series version of a project like this would be great (1.75" panel width, each channel an individual PCB) that could be built into a desk with 500 pres and modules. Wouldn't necessarily need to be limited to 3U high if more controls are needed.
A fader & balance pot, switches, and some aux buses. Cost would be low. Then each channel pcb could connect through bus wiring to a mix and bus output amplifiers in a separate enclosure.
I've wanted to build a module desk for some time and this would make it possible.

This is why I joined my first forum this year... I need one of these lol

 

[darth fader]

FWIW back in the 80s I evaluated offering a modular mixer kit series through my kit company.

In hindsight I'm glad that I demurred.

JR

The 80's was like, ten years ago tho

 

[13engrsapper]

Maybe just modify or use an old broadcast board? Look at some of the Auditronics, Wheatstone, Harrison, etc., any that had removable channel strips. As Brian mentioned, stay away form things which are one giant PCB OR one giant faceplate... "pain to maintain"

 

[13engrsapper]

I was doing some graphic design work for a company that was making a small desktop line level mixer, with automation/recall. I have the entire manual here still, I created the manual. This was about a year before covid. Covid hit, and everything shut down... and um, well. I know someone bought the idea, and I don't see that they have released it yet. It also offered balancing and enough makeup gain for racked gear that was lacking the output amp section. It was a pretty cool little rig - it was set up to work with your DAW.

 

[capacitorless]

I'm doing something similar to what @13engrsapper suggests, but it probably will not be as compact as OP desires as it's based upon a live board (channels removed, center section put in a narrower enclosure/built into a desk). It will be cost effective because it was picked up for a rather good price, and is of known sonic quality. Basically the back panel needs brought up to the top for I/O, and the power supply relocated, but all doable.

 

[Newmarket]

I'm up north in Dyer Indiana Close to chicago... which makes me a "Region Rat"

fwiw imnsho this site/forum is one of the best. Much top grade knowledge, support and advice. Even from people with whom I might / have disagreed on wider ethical / political issues.
OTOH do not invoke the wrath of the "bus(s)" police . Audio Phoolery also gets short shift

 

[Newmarket]

Maybe just modify or use an old broadcast board? Look at some of the Auditronics, Wheatstone, Harrison, etc., any that had removable channel strips. As Brian mentioned, stay away form things which are one giant PCB OR one giant faceplate... "pain to maintain"

Right along the lines of what I was thinking. But I'm not clear if OP is up for a DIY solution or only a ready made commercial offering.

 

[OneRoomStudio]

90% of my gear is DIY. If there’s an affordable commercially-available product, I wouldn’t say no to it though.

But if DIY, then the trick is to determine the best path forward. I could definitely repurpose an existing mixer of some kind, but then I’d have to match the control set (or at least, the holes and labels) that already exist. Building fully from-scratch could be fun from a circuit-design perspective, but I hate metalwork.

 

[13engrsapper]

My Minneapolis guy again! @OneRoomStudio. I will be back home to Minneapolis in Spring.

 

[ruffrecords]

@MidnightArrakis I have checked the original fpd file and the dxf it exported and the outline is definitely rectangular.

It seems there are two ways to import dxf files into fpd. If you start a new panel design and and under the basic shape option you select "Free shape from dxf file) all you can import is the outpine. If you follow this through you do end up with a rectangular front panel using the dxf file I posted.

The other way is upon opening fpd go straight to the File menu and select Import and the dxf file I posted. This appears to load the entire dxf file and then gives you options about which parts (Entire front panel or panel contour only or inner contours only) to load into fpd. The errors occur when you try to load in the inner contours most if not all of which are the printing. I modified the original fpd file so it specified printing rather than engraving, exported it as a dxf and then imported it into fpd in the hope these errors would disappear. Unfortunately they do not. It seems to me that the fpd function to import an entire panel in dxf format has some issues.

Anyway, here is the fpd file (with the extension changed to txt

Cheers

Ian

 

[ruffrecords]

90% of my gear is DIY. If there’s an affordable commercially-available product, I wouldn’t say no to it though.

But if DIY, then the trick is to determine the best path forward. I could definitely repurpose an existing mixer of some kind, but then I’d have to match the control set (or at least, the holes and labels) that already exist. Building fully from-scratch could be fun from a circuit-design perspective, but I hate metalwork.

I hate metalwork too which is why I try to use as much ready made stuff as possible. I can do front panels with FrontPanelDesigner and mate them with an attached PCB but that is really my limit. I recent;y got a 3D printer, which is an amazing thing, but I am going to have to bite the bullet and try to get my head around 3DCAD before long.

Cheers

Ian

 

[Newmarket]

90% of my gear is DIY. If there’s an affordable commercially-available product, I wouldn’t say no to it though.

But if DIY, then the trick is to determine the best path forward. I could definitely repurpose an existing mixer of some kind, but then I’d have to match the control set (or at least, the holes and labels) that already exist. Building fully from-scratch could be fun from a circuit-design perspective, but I hate metalwork.

I'd say it's practicable to drill new holes in the existing panel and / or cover existing holes as required. Also enlarging holes as required. All a lot less hassle and cost than getting front face panel and chassis metalwork from scratch imo.
Meanwhile, the thing about scarcity of line only hardware mixers seems analogous to the availability of audio interfaces without mic level inputs and the issue of whether line levels signals are handled separately or via the mic pres and likely padded down.Only seem to be offered in the 'big money" bracket. Not quite the same function I know but still notable.

 

[MidnightArrakis]

@MidnightArrakis I have checked the original fpd file and the dxf it exported and the outline is definitely rectangular.

It seems there are two ways to import dxf files into fpd. If you start a new panel design and and under the basic shape option you select "Free shape from dxf file) all you can import is the outpine. If you follow this through you do end up with a rectangular front panel using the dxf file I posted.

The other way is upon opening fpd go straight to the File menu and select Import and the dxf file I posted. This appears to load the entire dxf file and then gives you options about which parts (Entire front panel or panel contour only or inner contours only) to load into fpd. The errors occur when you try to load in the inner contours most if not all of which are the printing. I modified the original fpd file so it specified printing rather than engraving, exported it as a dxf and then imported it into fpd in the hope these errors would disappear. Unfortunately they do not. It seems to me that the fpd function to import an entire panel in dxf format has some issues.

Anyway, here is the fpd file (with the extension changed to txt

Cheers

Ian

[here is the fpd file] -- THANKS!!! I'll check it out.

[with the extension changed to txt] -- There's actually -- another way -- to rename a file for attachment to this forum!!! YA-A-AY!!! And, it actually has a very slight advantage over the conventional manner that is being used on here.

Instead of -- changing -- the filename extension to something else.....you just -- add it onto -- the existing filename extension, like this (as an example):

>> BasePanel7U40mm.fpd ..... becomes: BasePanel7U40mm.fpd.pdf

The "advantage" of renaming a file this way, is that whomever is downloading this file can easily still see what the original extension is. To rename an attached file done like this, all ya gotta do is delete the second extension, hit "Enter" and yer GOOD-TO-GO!!!

TRY IT!!!

>> By the way.....is it possible for you to attach/send along a -- STP -- file of your front-panel? And, maybe you could try the renaming trick above as well!!!

/

 

[MidnightArrakis]

Anyway, here is the fpd file

[Anyway, here is the fpd file] -- OK!!!.....So, I downloaded your -- .txt -- file, renamed it to -- .fpd -- and it loaded right into FPD!!! LOOKS GOOD!!! (Sort of!!!) Then, now that I had your file into FPD as it is supposed to be, I went ahead and exported it as an -- STP -- file and then imported that into my SolidWorks program. Surprisingly, the end result was only "kind of" OK and I was quite surprised!!!

Interestingly, your graphical "zeros" (i.e., -20, -10, etc.) somehow ended up becoming a "cut extrude" feature in SolidWorks. It also then made me think if the same type of thing might/would happen when this file is being 3D-printed. Here is how the STP version of your FPD file imported into SolidWorks:

>> The "0" in your graphics became an
oblong slot in the sheet-metal:



[the outline is definitely rectangular] -- YES, INDEED.....THEY ARE!!! (Sort of). Your front-panel had very crisp 90-degree edge-angles in FPD, but they all had a radius in SolidWorks:

>> Front Panel Designer

>> SolidWorks


>> I need to take-off right now to have some dinner, but I will need to check out why this is happening later on. While I am not all that familiar with using the FPD program, I have noticed that it does seem to have some variable parameters available in both the importing and exporting routines, which probably affects how the program imports and exports its external file formats.

CHOW TIME!!!.....

/

 

[Brian Roth]

Everything you say is correct. I am not suggesting complying with the synth boys Eurorack specification for everything. In fact Eurorack is a professional standard:

https://www.srs-products.co.uk/eurorack/

which the synth boys picked up and simplified for their own purposes. They called it by the same name. What I am suggesting is we use the same basic technique but modified for our needs. For example their modules are just front panels with components and PCBs hanging off them. There is no strengthening/screening metalwork such as in 500 series modules. They have a simple backplane PCB that carries power and some simple inter-module interconnects. The backplane connects to each module by a simple ribbon cable and all inputs/outputs are on the front panel. All of these techniques simplify construction and lower cost. What I am suggesting is we create our own pro audio backplane with some buses and feed it from a low noise +-15V supply.

Cheers

Ian

Thanks, Ian....that clears up a lot for me. Doing web searches for "7RU Eurorack" only came up with the synth versions...two rows of 3u and one row of 1RU with multiple mounting rails going from left to right. That design "breaks up" the possibility of a single 7U module. The one you linked in post #36 has that configuration.

Now I can focus on DIN-standard Euroracks <g>. How much does an empty 7RU frame typically cost? Here in the Colonies <g>, I am unfamiliar with the format or who sells the frames. More searching coming up.....

Best,

Bri