Completely Passive Stepped Monitor Controller

[HKD126]

I've been looking for something along the lines of this.

2 XLR inputs
1 aux RCA input (Or just a third XLR input)
3 XLR monitor outputs
L/R and main mute
Mono
Dim
Stepped Volume Control with 1db increments
Headphone amp with 1 output

I have been searching these forums religiously in hopes I may come across something. I am just curious as if to anyone has found anything along these lines? It seems there are very few options out there and none of which are quite what I am looking for. I have contacted several people that do custom work and have built great units for others... The general response I am getting is that they no longer do the custom units, projects have been put aside for other work, etc. Any insight would be greatly appreciated. Thank you very much.

[acorneau]

I think Coleman M3PH MKII has everything but the "dim".

Coleman Audio | Monitor Controllers

[HKD126]

I've considered it plenty but its not 1db stepped and the dim feature is a must have for me.

[Franco]

I don't know a lot about electronics (am teaching myself and currently reading books & I've build a couple of simple switchers) but I think you need power for an attenuator and the dim circuit. I think the switching can be done passively, but I believe stepped attenuators require resistors for the steps, and the dim will probably need a basic circuit as well.

Sent from my Droid using Gearslutz.com App

[MAzevedo]

Some things to think about:

First, obviously, the headphone amp can't be passive.
Second, does it have to be balanced throughout? A passive, stereo, balanced attenuator is going to be very expensive. Can the whole thing be unbalanced?
How many steps do you expect on the attenuator? Without getting into relays you are going to have 24 steps at best.

With those points made, this wouldn't be a hard thing to build, just rather expensive (for good switches and the attenuator) and some tedious wiring.

[Rob Murray]

What Matt said...

If you need it, build it. If not look at similar marketplace options like the coleman.

[sameal]

i scored a Coleman m3ph awhile back. really nice unit. the only thing it's missing is subwoofer management. that's really my only complaint. it's a good solid built unit otherwise.

i think you'd do well with this unit and not miss the dim or the 1db. but i don't know what your using those for so my opinion is moot.

maybe you could build a dim switch to put in the path? probably easier then hunting a unit with one.

[acorneau]

Originally Posted by HKD126

I've considered it plenty but its not 1db stepped and the dim feature is a must have for me.

Have you contacted the Coleman folks about making some modifications for you?

The "dim" function can't be more than a few resisters and could use the "phase" button since you don't need it.

The volume pot could probably be replaced by a 1dB stepped attenuator, like one from Goldpoint. (Not sure about physical dimensions though.)

Hell, if Coleman won't do it I'm sure you could buy the unit and then find a good tech that would do the modifications for you.

[Red Mastering]

I am at the end of the road, almost done
someone is building for me a monitor controller based on ldr (lightspeed attenuator) - so no stepped, but fully passive (google it, it's well known on diy forum)
it's not balanced (as my power amp is hifi tube amp) so I don't need it
all cables very short
I got 3 switchable inputs, connected to 1 output via (ldr)
it's not only passive, but also does not contain any electronic part (sorry but I'm knob in this area)
plus an option to switch in sub out (it's not passive this out) but it's for sub only so who cares?
also headphone class a amp (JLH amp), active (you could buy a ready made pcb off ebay, and then build power supply)
controller has a hand built power supply, in separate box;

as for a dim/mono - I use rme interface and use it's totalmix for those functions (actually bnc44 midi controller)
I was told that dim/mono, l/r has to be active and it's not pure audiophile approach, so I use midi controller for it

my point is - if you need something so custom - build it yourself, or find someone who can do it for you,
balance could double the cost, as someone mentioned, so maybe it's not worthy ?
also evey additional output has to either be another ldr circuit or active - big no no for audio purists,
I haven't tested mine yet, as it should be with me in few days (hope so),
but in theory ldr idea should sound better then any high end attenuator...
I'll test it and share with you guys,
also maybe some Londoner (South London is the best as I am lazy to travel) who own avocet or other high end attenuator is happy to do some test to compare it

peace

[sameal]

^ just grabbed one of those corded trackman units after using them at work all day.

very nice mouse. i made the mistake of going wireless. never again. just got back on the corded track.


totally off - topic. whatever.

[HKD126]

That is a really good idea to contact Coleman about doing the mod. Does anyone know of any other people that does custom work like this? So far everyone I contacted about this and has done it in the past no longer does custom work.

24 steps is all I need. I also realize the headphone amp would not be passive. I've considered doing this project myself, but the only experience I have with building gear is prefab'd kits. If I was going to sink a decent amount of money into this I'd like something a little more professional and better quality than I'd be able to come up with. Thanks for all the input.

[Waltz Mastering]

Originally Posted by HKD126

I have been searching these forums religiously in hopes I may come across something. I am just curious as if to anyone has found anything along these lines?

Found this guy who builds custom controllers:
Gallery | NF Audio

Dangerous ST here.

[Ben F]

Originally Posted by Waltz Mastering

Found this guy who builds custom controllers:
Gallery | NF Audio

Dangerous ST here.

NF audio is your best bet, or Igors from prodigy pro DIY has kits available. Just looking at the second hand section I've seen one by SPL and Cranesong I would just buy a used one, it's going to cost around the same money.

[Electrode]

Originally Posted by Franco

I don't know a lot about electronics (am teaching myself and currently reading books & I've build a couple of simple switchers) but I think you need power for an attenuator and the dim circuit. I think the switching can be done passively, but I believe stepped attenuators require resistors for the steps, and the dim will probably need a basic circuit as well.

Sent from my Droid using Gearslutz.com App

Dim & Attenuation is done via Resistors. These are passive components because they don't require power beyond the AC signal itself (the audio). An IC like a 5534 is active, because in addition to the input audio signal it requires DC power.

[sameal]

Originally Posted by Waltz Mastering

Found this guy who builds custom controllers:
Gallery | NF Audio

Dangerous ST here.

I really want a dangerous st. but i can't afford it. i couldn't Huck the Coleman for enough scratch. maybe in a few years the price might drop?

[HKD126]

NF doesn't do custom work anymore

[Radiance]

Originally Posted by HKD126

I also realize the headphone amp would not be passive.

If you want a totally passive audio path than the headphone amp will require his own feed. You can't split the audio signal into speaker and headphone feed without compromising audio quality.
Same goes for a mono switch although that's less of a compromise.

So, if you want a headphone amp and a mono switch, go active...

[spectrasound]

Goldpoint Level Controls

Top notch calibrated stepped switches. I bought one and built a passive panel with it...adding some sexy old API VU meters to compliment my Dorroughs.

[p-fort]

hi there,

I have this all passive monitor controller with three stereo balanced outs (2 variable, 1 fixed) / three balanced ins built by Dodocus

Includes a 41-step attenuator from Acoustic Dimension.

separate headphone amp required.

[Franco]

Originally Posted by Electrode

Dim & Attenuation is done via Resistors. These are passive components because they don't require power beyond the AC signal itself (the audio). An IC like a 5534 is active, because in addition to the input audio signal it requires DC power.

Thank you for explaining this!

[Bobine]

I built one of Igor's passive monitor controllers using relays.
1 db steps, accurate to .1db; down to -55db. Programmable Dim. I'm very happy with it.

Not an easy build, however.

[Electrode]

Originally Posted by Franco

Thank you for explaining this!

You are welcome. I should have been clearer though, Dim and Attenuation can be done successfully via passive electronics (resistors)... but it is possible to do it actively as well.

[8inthemorning]

Worth a check:
Stereo balanced monitor controller - QES Labs

[HKD126]

Interesting indeed.

[HKD126]

Anyone else have any ideas? After playing phone tag and emailing several more companies about something custom it looks like most are too busy right now for the project.

[Jerry Tubb]

Seems like the Coleman would be a good choice for passive.

Manley, Dangerous, etc. Or the Crookwood active Unit.

Going with an available unit, then adjusting your workflow to fit.

Or you can commission a custom unit, if you wanna go the expensive route.

I'm quite happy with a simple Goldpoint attenuator.

My DAW apps handle the other functions; mute, dim, solo, mono, etc.

And headphones come from the Benchmark DAC1.

JT

[HKD126]

Wow. The c3-2as looks amazing. Where can you get these? I tried finding prices but couldn't find them. About how much do they run? It really seems dead on for what I want other than being active. Any other recommendations for a quality active analog controller? Thank you very much!

[Lehmman]

Originally Posted by MAzevedo

...Without getting into relays you are going to have 24 steps at best...

Originally Posted by 8inthemorning

Worth a check:
Stereo balanced monitor controller - QES Labs

It seems they do custom works.
On the page they state having a special order unit with the 41-step control.

[Canopus]

Originally Posted by Jerry Tubb

I'm quite happy with a simple Goldpoint attenuator.

JT

the acoustic dimension switches should get into deeper detail:
acoustic-dimension attenuators

[M.o.T.s]

Originally Posted by spectrasound

Goldpoint Level Controls

Top notch calibrated stepped switches. I bought one and built a passive panel with it...adding some sexy old API VU meters to compliment my Dorroughs.

Really nice