New summing mixer

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JAY X

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Hi!

Just want to share some picture of my latest summing mixer. It is a modified version of a summing mixer i did some years ago, with neaw features in the front panel. I'm looking for opinions about the features. Because some potential users may like to have this or this.... ;D Basically I want to make sure the features are useful enough for studio use.

List of features:

1. Signal present / peak indicator at the output of the summing amplifiers. -20/-2 dbu.
2. Insert Blend fader and switch. (pre-fader).
3. Added a Mono switch to convert channels 1 to 4 in mono without loosing inputs. When engaged the MONO switch, channels 5-8 remain stereo. Otherwise with MONO disengaged all channels are stereo.
4. Output type switch as in the initial version. Selects output type: Electronic balanced Line driver or Lundahl transformer.
5. Big Mix output level knob as in the initial version.
6. And finally added Mix Output level Peak leds / Vumeters.
7. 32ch in db25 balanced format. But also a 16ch input version, upgradable to 32ch.
8. Balanced Send/return insert point pre-fader TRS jacks
9. Stereo TRS jacks for expansion input.
10. Mix outputs and multed Monitor outputs (to an external monitor controller) in XLR format.

11. Sound quality: I tested the mixer against an SSL Duality Delta, and we could compare the sound with a mix session they were doing: They sounded equal!! until we engaged the Lundahl transformer output (LL2811) in the Mikrosum... then we all could hear the difference: ¡Wow!! A good and punchy low end... 8)

I would like to have some opinions, or questions, I will answer here!!

Jay x

 

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JAY X

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Hi!

Attached is a picture of the rear panel:

Db25 inputs, TRS expansion inputs, and below, th balanced insert send return jacks. More to the left, the XLR outputs for MIX out and multed monitor output. And last but not least IEC input socket with fuses.

Jay x.
 

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JAY X

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Hi!

For anyone who could ask, the front panel serigraphy was made with a Roland UV printer. It was a not a simple process... First we had to draw the panel on paper, and then, place the frontpanel over it and align it. For a one off process is ok...but not perfect. For a series, it will be necessary to build a wood pattern to fit the panels/pieces and align them to the printer head. In thiscase the printing quality and detail capable of UV printers is far better than it would have been with traditional serigraphy.

Jay x
 

JAY X

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Y
ruffrecords said:
Just one question - when you switch the four channels to mono,do you simply pan them the the centre?

Cheers

Ian


Hi Ian!

Yes, but in a manner so that the volume remains constant. No difference in level between stereo and mono.
I asked some friends, studio owners, if this would be an interesting feature to have. For the Bass drum, Snare, Bass, and Voice.

Jay X
 

ruffrecords

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JAY X said:
Y

Hi Ian!

Yes, but in a manner so that the volume remains constant. No difference in level between stereo and mono.
I asked some friends, studio owners, if this would be an interesting feature to have. For the Bass drum, Snare, Bass, and Voice.

Jay X

I know what you mean. Id is something similar to add in front of a regular input (using 10K bus feed resistors) to provide a level control and a left/centre/right switch (see attached schematic).

Cheers

ian
 

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JAY X

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Hi Ian!

Interesting!.

Another option would be to try a balanced panpot... but this would need a quad pot...

Regards,

Jay x
 

ruffrecords

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JAY X said:
Hi Ian!

Interesting!.

Another option would be to try a balanced panpot... but this would need a quad pot...

Regards,

Jay x
I think it can be done with a dual pot. I am pretty sure NYD posted a schematic for it many years ago.

Cheers

Ian
 

JAY X

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Hi!

When I published this thread, I expected to have some feedback about the summing mixer, its features, I like this, I would like that,..etc..many views but few comments... ::) Now I'm in the process of building a track to be mixed by a friend at his studio. This way we will compare the DAW mix with the summing mixer, line driver output and Lundahl transformer output. Meanwhile, please chime in!! :)

¡¡Merry christmas, stay safe, and hope a better 2021 year!!

Jay x

 

JAY X

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Hi!

Here are links to raw mixes (not mastered), done within protools and with the summing mixer.

¡There is a difference in sound! ¿what do you think?

Jay x


https://soundcloud.com/azel909/protools-mix

https://soundcloud.com/azel909/mikrosum-s-mix32-transformer-output

https://soundcloud.com/azel909/mikrosum-s-mix32-line-driver-output-raw-mix

 

JAY X

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Hi!

¡Thanks for your comments!

This is the only way to know if I'm in the right track! ;D

In my studio I have 6.5" krk v6 monitors.(black cone). I can notice the difference, but i suppose it may be more evident with larger speakers or if I add a sub. This is why i ask for opinions. :)


Jay x


 

skipwave

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Nice mix!

I agree with innercityman in that I prefer the transformer balanced mix to the others, but my reason is a consistency I perceive. This may be phase shift in the crucial speech intelligibility frequency range which results in a reduction of perceived disconnectedness between the different instrument voices.

The transformer makes the mix sound more like a band in a room, while the digital sum and electronically balanced analog mix retain too much dynamic response on the leading edge of each instrument - so much so that the instruments seem to jump out of the mix and announce themselves as separate tracks.

In my opinion that is exactly what making a mix is meant to solve, the cognitive dissonance of listening to a piece of music with instruments playing together while knowing that it those instruments were separately tracked, edited, effected, and leveled. A mix makes all these separate components into a single artistic statement. Perhaps a bit idealistic, but in pragmatic terms it just makes it easier for me to focus on the music instead of the sounds.
 

JAY X

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Nice mix!

I agree with innercityman in that I prefer the transformer balanced mix to the others, but my reason is a consistency I perceive. This may be phase shift in the crucial speech intelligibility frequency range which results in a reduction of perceived disconnectedness between the different instrument voices.

The transformer makes the mix sound more like a band in a room, while the digital sum and electronically balanced analog mix retain too much dynamic response on the leading edge of each instrument - so much so that the instruments seem to jump out of the mix and announce themselves as separate tracks.

In my opinion that is exactly what making a mix is meant to solve, the cognitive dissonance of listening to a piece of music with instruments playing together while knowing that it those instruments were separately tracked, edited, effected, and leveled. A mix makes all these separate components into a single artistic statement. Perhaps a bit idealistic, but in pragmatic terms it just makes it easier for me to focus on the music instead of the sounds.
¡Hi Skipwave!

¡¡Thanks a lot fot your opinion!!

After reading your comments, I'm starting to think to get rid of the electronic line driver output, and just leave the transformer output. Very interesting comments on instruments and mix perception. I spend more time tinkering with circuits, than composing or mixing, so opinions like yours are what give sense to what i'm trying to build. Another idea I have is that i could add a -6db function switch, for primary transformer saturation...

Jay x
 

PermO

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I prefer the mix with the summingmixer, transformer version.
I do think the mix needs more work before sending for mastering.

Really love the appearance of your box, it's like you got it from a store.

A friend of mine has this industrial printer, it could do a full color frontpanel, but it is set up to do coffee mugs, so it would need a completely different mechanical setup... just for a couple of panels.
But you could get a coffee mug to go with your compressor...

Nice job !
 

JAY X

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¡Hi Permo!

¡Thanks for your comments!

Yes, the mix is a rough mix, so can be improved a lot!. These days I'm currently simplifiying the audio circuitry, less opamp stages to do the same job...:cool:
A coffe mug is a great idea!:)

Jay x
 

JAY X

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Hi!

One thing that keeps me thinking a lot is whether to replace the mix output volume dual pot for a stepped one for precise level settings. Some people say it eases recall settings. Is it important? What do you think?

Jay x
 

ruffrecords

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Hi!

One thing that keeps me thinking a lot is whether to replace the mix output volume dual pot for a stepped one for precise level settings. Some people say it eases recall settings. Is it important? What do you think?

Jay x
Depends on whether you want to use it to do a fade out or not. Stereo pots are notorious for poor balance so a stepped control would ensure the stereo image was always centred no matter what the setting of the control.

Cheers

Ian
 

JAY X

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Depends on whether you want to use it to do a fade out or not. Stereo pots are notorious for poor balance so a stepped control would ensure the stereo image was always centred no matter what the setting of the control.

Cheers

Ian
Hi Ian!

Not for fade out, just adjusting the mix output level going back to the DAW. I have seen a picture inside an SPL Mixdream XP, and it is a high quality big square blue pot...perhaps an alps.. In my case i use a 12mm 10k linear alpha 5% dual pot.

Another solution would be to use "stepped" linear potentiometers, like those used in the dbx 266XL compressor. Every time you rotate it, you get a small click. It makes recall settings easier. I don't know where to find these ones, but they are bigger in size: 20mm diammeter...😆

Jay x.
 
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