Equipment Hire





Exchange and Mart


Unit 127
J C Albyn
Burton Rd
S3 8BZ
0114 270 1470



Nightingale Audio Systems Ltd


Our 32 channel Summing mixer and monitoring unit.

Update Mar 24. OOPs. I got so busy with things that I havent updated this in a while. I have 4 of the new and shiny units built. They sound amazing. They look really good. Talk to me about them. I will put up a picture real soon.
Update April 28th 2021 The new boards arrived at the end of last week. I have built one input pcb and one master. I am forcing myself to be calm and not rush into powering them up just yet ( thats for tomorrow )

new boards

Update april 8th 2021. I finally stopped tinkering with the master board and send off for the new pcb's. I need to update the feature list as I have added an extra Alt input to feed the Studio. This means that you can now feed the studio with either the full mix or the 2 track return in stereo or mono, or you can feed an Alternate mix to the studio ( like an individual cue mix ) The bare pcbs should be here by the end of April and I am very excited.

New Boards for the SMX-32.

new main mix board

new input board

Of course adding new bits means that the new front panel is in need of updating.

new dummy front panel for the SMX-32

This was the new front panel for the SMX-32.

This is a page dedicated to trying to put information about the new mixer and how it is going. It is being written sort of on the fly and isn't going to be a shiny sales page but I will try to keep it up to date.
It is also part of the learning strategy. I need to know what you want to know
If there is any information that you would like about the box please ask.
I will try to reply to you asap and also put the info on here.

I have a 16 channel version in my project studio with currently a 16 channel interface hooked up to it. If you wish to come and socially distantly demo the unit please let me know.

mix box

Here is my 16channel mix box in the rack.

Entirely handmade and tested in Sheffield

My intent is that these will be almost entirely hand built and hand tested here in sheffield.
There are no pcb manufacturers in sheffield any more so they will be coming from one of the 33 remaining pcb manufacturers in the UK and not from China.
The power supply that I am currently using is made abroad but for emc and safety testings sake it seems the best idea initially.
I may play with a linear internal supply once I have finished the the first couple of BETA units.
Apart from those things it will be pretty much done by hand. Yes it makes it more expensive but I would like to keep some skills here in the UK and some pride in our stuff.
It does have price implications though which may put some people off.

Feature list of the SMX-32

32 mono electronically balanced pan-able channels.

Stereo mix insert points.

Electronically Balanced main outputs.

Monitor the mix or a 2track input.

2 switchable balanced monitor outputs with mono, dim and mute function.

Headphone output that follows the monitor source.

Balanced Studio feed that follow the monitor with a talk back facility.

All connections on TRS Jacks with the option of putting the inputs on 25 way D connectors.

Entirely analogue technology.

Opinionated design. ( I like this phrase. That I have an opinion about my mixer is a selling point apparently.)

rear of mix box

Here is the rear my 16channel mix box in the rack.

Some of the specs.

Max input level 20dBu (though this may be due to limits of my test equipment)

Max output level 20dBu ( again see test equipment )

Frequecy range 20Hz (-0.7dB) to 20KHz (-1.5dB)

SMX-32 frequency responce input to main output

you can see that the frequency responce is quite acceptable buuuuut..........

SMX-32 enhanced frequency response

I sort of went "what happens if I change that value......".
I don't think that I need the box to have that good a response so I will let you know what I settle on.
Noise floor is below my current ability to measure - but it is quite acceptably low.

SMX-32 Things Left to do.

Here is a list of things that I need to do to make this a complete thing.

Re-spin the CAD on the main board to incorporate all the additional circuitry. I am currently on with this.
Re-spin the CAD on the input board to rectify routing / placement mistakes.
Tweak the artwork for the front.
Check that all the new metal work will fit and line up properly
Sort all the EMC and saftey certification.

Things that I would like to do.

Get a dragon worked onto the front panel somehow. Yes it is a sad fact that I like dragons, we have a local dragon legend and I don't think that it should be ignored. There are so many cool images of the Wantley Dragon that it is worth googling them.
Try an internal PSU. I dont know if people would prefer an internal or external PSU. A little feedback on this would be good.

inside the mix box

THis is what it currently looks like inside. A bit of a mess but that is why I am respinning the CAD.

SMX-32 The story so far.

A few years ago I went to a studio to do a repair to a vintage desk and the engineer showed me a summing box that they had acquired.
I pointed out that it did a lot less than his desk did so he asked me " How hard can it be to design a 'summing box' which works like a desk?"
The answer has been - quite honestly - harder and easier than I thought.

I started with a few scribbles on the back of an envelope and six months later I had a mixer that did nearly what I wanted it to do. Still something that I found fairly easy.
I called it my 'Mix Box' - I am an engineer, not a marketing guru! It was a box, it mixed things, what else should I call it.
Over the following years I used it and came up with a list of things that I would like to change but as it wasn't getting in the way of me using it I just made notes of it and added it to the to do list.
Early 2019 a band that I have done some work with for the last few years called me in a panic as their recording desk had died and they were trying to mix their album down. They were on a deadline. I installed my 'Mix Box' in their studio. They finished the album. They gave me feed back. We went on tour. I pried the box back out of their studio at Christmas with the intent of doing a Beta version. We went back on tour.

Then covid struck and everything stopped.

Over the summer I did some tinkering and worked out all and documented all the changes that I needed to do to it.
I have worked out the design for the physical box, played with artwork, found fabricators, powder coaters, screen printers.
I also changed its name to the SMX-32 as it is a Studio MiXer with 32 inputs. ( Still not a marketing Guru ) Now I have a unit that is somewhere near.
Currently I am re-working the main mix and monitor pcb.

Preaching to the converted

I could easily go on a long tangent about mixing in the digital and analogue domains but I am going to show restraint.
Digital is incredible! Analogue sounds better! combining them can take you to new heights!

0114 270 1470