ruffrecords

Re: All Tube Sidecar
« Reply #80 on: February 06, 2018, 06:31:45 PM »
http://www.neutrik.com/en/xlr/xlr-chassis-connectors/d-series/


Bri

Thanks mate. So basically NC3FD-H* and NC3MD-H*. 

I'm spoilt for choice.

Cheers

Ian
« Last Edit: February 06, 2018, 06:48:13 PM by ruffrecords »
www.customtubeconsoles.com
https://mark3vtm.blogspot.co.uk/
www.eztubemixer.blogspot.co.uk


'The only people not making mistakes are the people doing nothing'


Brian Roth

Re: All Tube Sidecar
« Reply #81 on: February 06, 2018, 06:36:42 PM »

PS. A few posts ago I said the monitor would need only to switch between the master bus and 2TK playback for A/B comparison because the Solo feature would let you set levels/check quality of individual channels. However, I forgot about the AUX sends. So a third postion on the switch is needed to accommodate these.

Cheers

Ian

On various Neve and Amek desks the monitor had a switch for "internal" and "external" sources.  Then, two banks of switches selected stereo mix, auxes, etc for internal and several " 2 track" sources for external.

Bri

Brian Roth Technical Services
Salina Kansas, home of the best vinyl on the planet!

http://www.BrianRoth.com
recordingservicesandsupply.com/
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store.acousticsounds.com

ruffrecords

Re: All Tube Sidecar
« Reply #82 on: February 06, 2018, 06:53:39 PM »
On various Neve and Amek desks the monitor had a switch for "internal" and "external" sources.  Then, two banks of switches selected stereo mix, auxes, etc for internal and several " 2 track" sources for external.

Bri

Internal or external - that's a good way of thinking about it because it will actually mean something to the guy/gal operating the desk.  Good thought.

Cheers

Ian
www.customtubeconsoles.com
https://mark3vtm.blogspot.co.uk/
www.eztubemixer.blogspot.co.uk


'The only people not making mistakes are the people doing nothing'

pvision

Re: All Tube Sidecar
« Reply #83 on: February 07, 2018, 06:17:40 AM »
To my way of thinking this is two units in one: a bunch of channel strips and a routing / monitoring module

When I think of channel strips I tend to think of the Focusrite channels you see racked up



In this case they are used just as channel amps. If you used the same approach, and created a channel amp with very little complexity, IMHO you'd open it up to a wider audience and more uses

A channel strip needs a mic / line amp, EQ and, ideally, an insert. Having the insert switchable pre/post EQ would be good. That saves all the complexity for a routing / sends / fader module

Going back to the Focusrite modules: they are racked up. If your modules are 35 wide then you'd get 12 in a 19" rack. You could use a 19" panel for the monitoring section. And a 19" rack power supply. Users who wanted to work mobile could have a rack of pres, with or without the monitoring section. Static users could have a sidecar setup

This is going away from your original concept. I don't throw the idea in to confuse, just as an idea to provoke thought & discussion. Also, separating the active parts from the switching & routing might help nail down what the proposition is, and what people want

Nick Froome

ruffrecords

Re: All Tube Sidecar
« Reply #84 on: February 07, 2018, 12:01:07 PM »
Physically separating the functions of mic pre/EQ and routing is the classic Neve format. Perhaps that is one reason the channel amps are so popular racked on their own. And of course Focusrite is (now) a distant cousin of Neve.

The API 500 series approach is different. The mic pre and EQ are separate (smaller) modules which provides added flexibility.

Both methods allow different channel strips to be created (and used alone) by keeping routing separate.

The Mark III design started from the premise of trying to fit in twice functionality per unit width compared to the EzTubeMixer project to bring it in line with current products and avoid need for one metre of width for a 12 channel console as in Holger's wonderful Krassemaschine. As a first step I designed some 6U modules of the same width as the EzTubeMixer modules but each containing two channels. This saved me having to completely redesign all the PCBs and the mechanics but meant that these modules would be line in only because I had the same number of amplifiers but twice the channels to provide for. This was deliberate because current practice seems to be often to use outboard mic pres of various sorts fed directly to a DAW and possibly use a line level mixer (LILO) for monitoring and mixdown. I am sure this is the case because because I have sold several lunch boxes containing just tube mic pres and nothing else (not even EQ) and I have an order for a LILO mixer.

I then started experimenting with half width (35mm) modules which involved mounting the tubes vertically and completely redesigning the PCBs and mechanics. This allows not only twice the modules but twice the number of amplifiers (tubes) per unit width compared to the EzTubeMixer. The problems involved in doing this I believe I have now pretty much solved so the remaining question is simply one of how to package things. I can still supply mic pres alone in a 3U lunchbox but now I can get up to twelve in a lunchbox rather than the present six. The next step would be to add EQ, possibly in a 6U unit, which would be similar to the Focusrite modules you mentioned and could be racked similarly and I have begun the design of the first of these containing my REDD EQ design.

The first problem arises when you try to fit other EQ types, like the Helios 69 or my 3 band Pultec design into a 35mm wide module. The REDD fits because it has only 4 controls total. The Helios has 6 and the Pultec has 7. It is very hard to fit these into 35mm width without resorting to expensive dual concentric knobs and/or tiny unusable (in my view) knobs. The Focusrite illustrates this perfectly. I also think it is important for all EQ controls to be stepped (for accuracy, tracking and repeatability) which only the REDD achieves at the moment. So,based on the mastering EQ which I am also developing at the moment, I have devised a simplified three band version with stepped boost/cut controls and three selectable frequencies per band which fits neatly into a 35mm wide 3U module and does not need the fingers of a pixie to operate. This is the EQ I plan to use in the tube sidecar and also can be added to a 6U channel strip version (perhaps with added features like HPF and LPF). Either of these 6U modules could then be supplied in racks or used as channel strips in mixers.

The sidecar project is at least in part defined by my desire to fit it into the Glensound and EELA frames I have purchased. Both have a 3U section at the top in which I plan to house the mi pres. The Glensound has a second less deep 3U high section that the new EQ will fit in. It then has a fade section below which can also have Solo, Mute and Direct buttons. In this instance, the only available space to put the routing is in the mic pre module. This means the routing is relatively simple (pan plus two AUXes) but it does mean the overall mixer is really compact - it is only 500mm wide and it could be configured as an 8 into 2 or even a 10 into 2 which would make is smaller than a Neve Kelso.

So, to summarise, it is what it is right now because the Glensound provides me with a framework (literally) to work on and will actually produce something useful at the end. The 'final' version of the sidecar would undoubtedly have a custom frame that would allow the channel to be either two 3U units (mic pre and separate EQ) or a single 6U channel module, and routing would be a completely separate module. Any of thes modules can be use to make rack mounted pure mic pres or channel strips.

You can see I have a lot of work to do which s the main reason I am not taking any commissions at all  this year. I really want to get the Mark III sorted.

Many thanks for your input.

Cheers

Ian
www.customtubeconsoles.com
https://mark3vtm.blogspot.co.uk/
www.eztubemixer.blogspot.co.uk


'The only people not making mistakes are the people doing nothing'

Re: All Tube Sidecar
« Reply #85 on: February 09, 2018, 03:26:34 PM »
It's a great project Ian! Any photos yet?

ruffrecords

Re: All Tube Sidecar
« Reply #86 on: February 09, 2018, 05:44:34 PM »
It's a great project Ian! Any photos yet?

It is all very much up in the air at the moment. I have got the PCBs for the little 3 band EQ which I will be building and testing in the near future. I also have a prototype front panel for that on the way so that will be the first tangible part I can take a picture of.  The mic pre is based on my Classic design which is currently in prototype as the UniVert (Universal Vertical Tube Preamp) (I think I posted a pic of that a while back in another thread). That PCB is being modified to comply with the new motherboard pin out that Holger and I devised to cater for the next generation of tube modules. The good old Twin Line Amp has been repackaged into a 35mm wide module. That PCB is ready to go and I am still working on the new 12 module motherboard. I expect to have all these ready for manufacture by the time the Chinese get back from their New Year celebrations.

I have spent a lot of time sorting out components. With such a narrow width module I wanted a scheme that a still allowed neat front panel layouts so I have standardised on MRK rotary switches and Alpha 9mm vertical mounting pots. These all mount on a PCB that sits parallel to the front panel which allow pots and switches to be lined up neatly. I wrote a post in my blog about this awhile back (and also about the Univert mic pre and the new module mechanics:

https://mark3vtm.blogspot.co.uk/

Cheers

Ian
www.customtubeconsoles.com
https://mark3vtm.blogspot.co.uk/
www.eztubemixer.blogspot.co.uk


'The only people not making mistakes are the people doing nothing'

pvision

Re: All Tube Sidecar
« Reply #87 on: February 14, 2018, 10:33:22 AM »
Just had a good read of your thoughts re the project, Ian, and have only one suggestion: put the HP filter on the mic amp module

This frees up panel space on the EQs (or allows more free space, depending whether an HPF was planned or not) and allows it to be put where it is most needed - on the mic pre

Nick Froome

ruffrecords

Re: All Tube Sidecar
« Reply #88 on: February 14, 2018, 12:41:04 PM »
Just had a good read of your thoughts re the project, Ian, and have only one suggestion: put the HP filter on the mic amp module

This frees up panel space on the EQs (or allows more free space, depending whether an HPF was planned or not) and allows it to be put where it is most needed - on the mic pre

Nick Froome

Probably a good idea. The EQ module really has no room for this. To illustrate, here are a couple of pics of it (I just received the prototype front panel today and, after a little fettling, assembled the basic module. First pic shows the front panel:



As you can see there is little if any room to spare. I need to squeeze the EQ in/out switch in right at the top centre but there is certainly no room for an HPF as well.

Second  pic shows how the two boards fit together:



The EQ is based on the new mastering EQ topology scaled down to three bands. Its advantage is it gives peaking boost and cut in all three bands. I called it the REDDPLUS because the Q in all bands and the mid frequency selections are much the same as my original REDDEQ design.

Cheers

Ian
www.customtubeconsoles.com
https://mark3vtm.blogspot.co.uk/
www.eztubemixer.blogspot.co.uk


'The only people not making mistakes are the people doing nothing'

kambo

Re: All Tube Sidecar
« Reply #89 on: February 14, 2018, 02:20:44 PM »
if i had to choose between shelving HF vs peaking HF EQ, i would pick shelving,
i dont remember using peaking eq at 9K-19K range, unless its surgical work!


pvision

Re: All Tube Sidecar
« Reply #90 on: February 14, 2018, 03:21:39 PM »
I completely concur with your dislike for cramped panels. So maybe offset the switches on the EQ from the pots so there's more finger room?

The mechanical construction is very sweet

Nick Froome

ruffrecords

Re: All Tube Sidecar
« Reply #91 on: February 14, 2018, 05:19:11 PM »
I completely concur with your dislike for cramped panels. So maybe offset the switches on the EQ from the pots so there's more finger room?
At the moment, the knobs (which are rather nice Sifam ones) are a lot taller than the toggle switches so they don't get in the way when you operate the knobs. However, they do look better when offset as in your illustration and what is more, that would make it easier the fit in the EQ in/out toggle above them. Nice idea, thanks. By the way, the knobs are 14.5mm diameter at the base so they are not the smallest available but the do nicely cover the switch nut. Now I have the panel I might try some 11mm diameter ones.

The vertical spacing is certainly fine - the rotaries are on 30mm centres.
Quote
The mechanical construction is very sweet

Nick Froome
I am mechanically challenged so it takes me absolutely ages to do this stuff. What you now see as 'sweet' is the result of several years plodding. Even then I cannot take much credit. The little die castings are the key to it and they are standard Eurorack parts made by all the sub-rack manufacturers like Schroff, Fischer and SRS and are designed specifically to connect Eurocards to front panels.

What I can claim credit for is extending this idea by making provision for two more such die casting one the right side of the front panel which allows you to attach a steel screening plate to the front panel. At the rear of the PCB you fit a pair of pillars to connect the back end of the PCB to the back end of the steel. The whole forms a very tough rigid structure. Top and bottom are open which allows free flow of air past any tubes.

The other thing I am proud of is finding a set of good quality vertical PCB mounting components (pots, rotary switches, toggles and push-buttons) that are almost exactly the same height above the PCB. This means you have great flexibility in positioning controls when designing front panel layouts.

Cheers

Ian
« Last Edit: February 14, 2018, 05:22:19 PM by ruffrecords »
www.customtubeconsoles.com
https://mark3vtm.blogspot.co.uk/
www.eztubemixer.blogspot.co.uk


'The only people not making mistakes are the people doing nothing'

pvision

Re: All Tube Sidecar
« Reply #92 on: February 14, 2018, 06:41:34 PM »
Those 14/5 mm Sifam knobs are excellent. There are some similar, cheaper ones at Rapid made by Cliff and some more expensive ones from OKW

Rapid also have some shaft joiners & flexible couplings which are esoteric but potentially useful for some projects

Have a look at this search
https://www.rapidonline.com/knobs?ra_source=tier-left-list&Attributes={%22Shaft%20Diameter%22:[%226mm%22],%22Fixing%22:[%22N%2FA%22,%22Push%20fit%22]}&Size=60&ResultsTotal=30

I've found it really difficult to find suppliers who carry a decent proportion of the Sifam range. Most have limited colours & sizes. There's a Eurorack synth module supplier close to me, Thonk, that has a good range

https://www.thonk.co.uk/product-category/parts/knobs/


Nick Froome

ruffrecords

Re: All Tube Sidecar
« Reply #93 on: February 14, 2018, 07:04:12 PM »
I use Thonk quite a bit because they also do the vertical ALPHA pots. They do a great range of knobs but unfortunately no 1/8 inch types.

Your Rapid link gave an error. I'll try again later.

I agree it is incredibly difficult to find one supplier for all your knob requirements.

Cheers

Ian
www.customtubeconsoles.com
https://mark3vtm.blogspot.co.uk/
www.eztubemixer.blogspot.co.uk


'The only people not making mistakes are the people doing nothing'