24 channel mixer the "Stereotype"

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Hi, great work there, I would be interested in some boards, depending on how you decide to produce them...I would prefer screw terminals for I/O over a db25 mounted on the pcb. thanks again.
 
Cool.. I'd love this, but am working on my own summing/routing box that has an L/C/R switch for every channel for pan and a mix/through/insert switch. Mix routes the channel to the LCR buss, through routes it to a direct out, insert routes it through a direct out and switches line B input of the same channel to LCR. I was thinking about it being a passive design, but this one being active is peaking my interest.

I'd be inclined on using your solution for panning though. If you'll be stamping those out, I'd like 24 of these mini pan switch PCBs very much.
 
So since there seems to be quite a few people interested in the pan boards, I'm thinking of doing a run. the only question i have is, would everyone want them as is (7 position) or would you guys prefer a revision allowing it to be a 9 position? The switch the board uses is a 1-10 adjustable stop grayhill. You could always put jumpers in a use less positions. Obviously I think 7 positions cover things, but let me know what you guys think.

Don

also, I'm still figuring out the main boards but some kind of run will be done in the near future on those as well
 
Well, more postions can't *hurt* now can they.. seeing as the chosen switch already supports it, i vote for 9 pos.
 
so I had a "duh" moment tonight. I am going to revise the boards so that they make full use of the switches and can accommodate as large a variety of parts as you can fit on a 1x1 board. This way anything you want a grayhill switch for, here is your circuit board. I think this makes the most sense by far. I'll keep you posted
 
hakanai,
I would love to build and have one of these, but unfortunately, a CT scan of my wife Monday revealed a new growth.  She got word today.  She has survived 2 goes at breast cancer and the treatments, but I'll have to curtail my diy until we know exactly what is going on.  She is scheduled for another CT in 3 months,  I'm sorry to have to back out, but she is my top priority.
 
well sh*t, I feel somehow "don't give it another thought" doesn't quite carry enough weight here, but don't give it another thought.

And good luck with all that lies ahead.

Don
 
Thanks for your understanding, we've been together 37 years.
Please don't anyone let this slow this wonderful project.
 
And on the 'not slowing down' note, I have been working a ton on the board revision for the mixer. I am trying to incorporate a few options and make the board as easy to work with as possible. The three main changes to the board are: 1. Everything on screw terminals (no pcb db25) 2. optional fader/attenuator insertion 3. optional dc blocking caps on the inputs. Is there anything else you guys would like to see incorporated? I'm not promising anything but if it is simple, I don't mind.

The Grayhill switch boards are done and are all set to be a 10 position switch. So now you just adjust the stops and put in a few jumpers and you have anything from 10 to 2 position switch. I'm contacting the fab house today about quotes so I'll have some numbers for you guys tonight or tomorrow. The mixer should be all figured out by this weekend and I should have some quotes on those boards by monday.

Don
 
So I just received the quote for the pan boards. It looks like I can do sets of 8 for $30. It seems like a few guys are interested, but anyone who is ready to commit please email me. I'm not going to collect any money until the boards are in but I want to know exactly who will order what.

thanks
[email protected]
 
Oh and someone asked earlier what i am powering my mixer with. The answer to that is actually another new addition to the Hakanai family. I call it the DC8. It's half 500 series half 200 series and the power supply is good for over 3A with an aux out on a 5 pin xlr that pin for pin with the api power supply and racks. I'm not sure what the future of this guy is. Not such a pretty picture this time. Since it's still being finalized I haven't brought the nice camera down yet.
IMG_1052.JPG
 
hakanai said:
So I just received the quote for the pan boards. It looks like I can do sets of 8 for $30. It seems like a few guys are interested, but anyone who is ready to commit please email me. I'm not going to collect any money until the boards are in but I want to know exactly who will order what.

thanks
[email protected]

Hi,
http://www.audiomaintenance.com/acatalog/GR-03-002_extended_info.html is this the correct partner switch to the PCBs?

Cheers,
B.
 
hakanai said:
And on the 'not slowing down' note, I have been working a ton on the board revision for the mixer. I am trying to incorporate a few options and make the board as easy to work with as possible. The three main changes to the board are: 1. Everything on screw terminals (no pcb db25) 2. optional fader/attenuator insertion 3. optional dc blocking caps on the inputs. Is there anything else you guys would like to see incorporated? I'm not promising anything but if it is simple, I don't mind.

The Grayhill switch boards are done and are all set to be a 10 position switch. So now you just adjust the stops and put in a few jumpers and you have anything from 10 to 2 position switch. I'm contacting the fab house today about quotes so I'll have some numbers for you guys tonight or tomorrow. The mixer should be all figured out by this weekend and I should have some quotes on those boards by monday.

Don

Since I don't have too much of an idea as to what you've already got in each channel's path, I may be off track...

What about a per-channel insert spot?  That would give folks who want to (now or in the future) use this as the core of more of a line-level console a place to put dynamics and EQ.

 
I'm not against the idea of an insert point per se, but I have never understood why you would need one on a line level mixer. It has always just seemed to me that the input of the mixer is essentially the return of an insert loop.
 
Ok, so I wasn't about to post this, but what the hell.. maybe someone finds it interesting.

I'm designing a 4U passive line-level mixer with an integrated preamp, like this:
SumFrontPanel4UPans.png


Basically, it's 24 line ins with your pan PCBs.. with a 3p4t rotary to select a destination buss and two switches, mode and input.

Every channel has 3 "I/O" points. Input A, Input B and Direct Out. Input A is always routed to Direct Out. Toggling "Input" switch on a channel selects either Input A or Input B as the channel's input. Mode in the "up" position means use this channel for summing and applies the mixing resistors to the selected input (A or B) and "down" position disengages any mixing of the channel. Effectively, all the channel does in this mode is pass A to Direct Out without any fuss.

Buss outputs can then be preamp'd externally and another summing network sums them up to stereo with pan for each bus subchannel (L and R separate pan).

There's a preamp on the main buss already and its gain is controlled by the gain knob. Int/ext controlls whether the internal or external preamp is used. 2BUSS would route buss1-2 (without preamplification, bypassing the buss pans as well) to the inputs of the main preamp.

I know this seems a bit convoluted and weird, but regarding existing passive summing solutions I dislike several things:

-- Most have stereo inputs only
-- Some that have mono inputs, have a fixed number of them on fixed channel numbers
-- there is no bussing, i.e. I can't do analog summing to channels 1-8 where my drums are to compress them analogue before going to the 2mix
-- you can do that with a DAW (mix the drums there, put them on a stereo stem track and mix that) but I find that to be defeating the whole purpose
-- they are not easily defeatable, so if I have 24 outputs from my D/A converter fixed to the summing amp, and I want to overdub something, or use a pair of channels for headphones while doing something like that, I'll have to disconnect a number of channels I deem to need and connect them elsewhere, or buy more output channels so that I can use them independently of the summing amp
-- they have no hardware inserts or they are not defeatable (toggle with/without insert processing)

In essence, this idea of mine solves these problems when having it connected like this:
-- all output D/A channels are connected to line A input of summing channels
-- direct outs are on the patchbay
-- line B inputs are on the patchbay

Thus, in order..

-- Any channel can be mono or any channel tuple can be a stereo pair, with adjustable panning
-- there can be any number of mono/stereo combinations
-- there is bussing and a stereo busses may be treated like a mono buss pair
-- by toggling the "mode" switch, I can use a D/A output channel as a headphone feed. My headphone feed is going to appear on the patchbay on the appropriate direct out channel number, unmolested by mixing resistors
-- by toggling the "input" switch, I may patch in external gear by taking signal from "direct input" and routing it back to "line B input" of the same channel. I may defeat this "insert point" by toggling the "input" switch


So, yeah... there could be a lot of problems in doing this design passively and probably noise buildup, so I'm open to suggestions, maybe even to see it modified to an active box!
 

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