rainton

Hey guys,

here's the thing: I built a couple of tube mics recently, and since I'm located in Europe I always had the problem to get a nice vintage looking Mic PSU chassis for my projects.
Twice I ordered the PSU chassis from Collective Cases, and even though it looks quite nice:

a)  it's very expensive to have it shipped over here from the states (chassis + shipping + tax = approx. 125 Euros)
b) it's a  lot of drilling and extra work
c) the quality is ok, but it could be better


And since I made my first successful steps of designing some chassis with my LA2A chassis group buy I figured why spending a lot of money on a PSU chassis I'm not completely happy with, when I can design my own one instead :)

I wanted to have a really high quality chassis, as close as possible to the vintage original Neumann PSU chassis in terms of looks, and I wanted it to be a breeze to build a tube mic PSU with it.

So before I write a novel here, I'll post some pics of my finished prototype (for a MK-U47) and thenI'll explain:

OUTSIDE:





INSIDE:

Here you can see this is not just the external chassis, but also a dividing panel inside with all cutouts, holes necessary to mount the components easily:





In the last pic you can see the dividing panel also includes an integrated mounting bracket for the voltage adjustment pot.
The way this pot is installed allows for turning the pot  with a screwdriver through a small hole in the front of the chassis.

Here's a close-up:


But not just that - there are also some holes in the bottom of the chassis where a pair of banana jacks (or something similar) can be installed. So if you want to readjust the voltage, you don't have to open up the chassis, you just flip it over, plug in your multimeter from the bottom and readjust the voltage from the front with a screwdriver:




Also there's a second mounting hole for another pot in the dividing panel if needed.
Basically, apart from the obvious cutouts on the outside(XLR, IEC, Binder, etc)  this chassis offers all holes necessary to mount:

- power transformer
- pcb(s)
- choke
- adjustment pot(s)
- cutouts for wiring/enough space for components

and most holes, (power tranny, choke, handle, feet, fastening holes for the lid...) even include high quality stainless steel nuts punched into the chassis for a smooth ride while mounting the components.  8)

The chassis itself is made from steel with a dark grey hammer finish and the material is thicker and more sturdy than e.g. the collective cases psu. The chassis is a 100% made in Germany.

Also the chassis will come with feet and a really nice & sturdy leather handle which feels great when holding the chassis. ( I always found the one on the cc-psu to be a little flimsy)

Here's my old Collective Cases chassis PSU I built for a U47 compared to the one I designed to be my new standard :)


On this picture you can see, the Collective Cases chassis definitely looks cool! And if you're located in the US it's great for the price!!

But I wanted to do something with a really authentic vintage look, that offers everything needed to make building a tube mic psu a breeze. And when I built this prototype - I'm telling you - I never had that much fun putting a mic psu together  ;D

Here's another pic without components:

The one I built is made for a U47 type mic, but actually I want this chassis to be suitable for as many tube mic projects as possible.
And I wrote above that the chassis will even include the holes for the pcb.
At the moment this includes only Zayance's MK-U47 psu pcb, but I want it to include the necessary mounting holes for all other popular tube mic projects out there.
Also my U47 pus doesn't need a pattern switch on the PSU so I didn't include it.  But I thought about a way to create a mark inside the chassis, so if you need a pattern switch, it's easy to drill a hole at that spot to install a pattern switch

So this feeler has 4 main goals:
- finding out if there's a greater interest in such a nice PSU chassis
- getting the dimensions of as many different mic PSU pcbs as possible, so I can include their correct footprints (mounting holes)
- how many want the cutout for the mic to be XLR, how many want the larger Binder/Amphenol, any of you want the original tuchel?
- should there be a hole for the pattern switch by default, or should I just leave a mark inside the chassis for the right spot to drill?

I'm aware the way I designed it is not the cheapest way to go (it will still be for European builders though), but it's definitely by far the easiest and most elegant way  :D

That said with all the above mentioned included we only reach an acceptable price range if we are as many as possible.
So including everything stated above with more than 20 chassis made we look at 119 Euros each. (excl. VAT if applicable)
If we reach more than 40 it'll come down to 105 Euros each.

And that's the 5th reason of this feeler which I want to open to discussion:

- Do you rather pay a price like this and have only high quality parts (e.g. thick leather handle) and the convenience of things like  punched in stainless steel nuts
- or do you rather save on a couple of bucks and sacrifice ease of use

Because - I'm sure it would be possible to design it a little cheaper (e.g. getting rid of the nuts, choosing a lower quality handle, no feet, etc) , but certainly not that much since the most expensive parts, are the complex dividing panel and the bottom chassis.

And I think with the Collective Cases chassis there's a great lower cost option out there - at least for US builders...

Ok, guys I'm really interested in your thoughts.

Here's THE LIST - please check if you're on it and if I got the correct number of chassis you want :)

lampas (2) PAID
DerEber PAID
Upacesky PAID
chefducuisine   (2) PAID
mrcase  PAID
dmp (4) PAID
bancho  PAID   
jafo  PAID
tskguy   PAID
Sredna (2) PAID
simonlef PAID
radiobug (2) PAID
kosi (2) PAID
craig (2)  PAID
stelin (2) PAID
CBR (6) PAID
jpharao (2) PAID
roger.unc (2) PAID
59flame PAID
olebrom PAID   
nattycee  PAID
flatresponse (2) PAID
fazeka    PAID
jackinthebox (2) PAID
Zander PAID
Mans Lundberg (2) PAID
gbruler (2)  PAID
Aaudio (2)  PAID
duantro PAID
mrerdat (2) PAID
rainton (3) PAID
poctop PAID
mellsonic (2) PAID   
« Last Edit: August 01, 2016, 12:16:42 PM by rainton »


Re: FEELER: THE ULTIMATE Mic-PSU chassis - VINTAGE NEUMANN STYLE!! OPEN!
« Reply #1 on: November 30, 2015, 12:25:44 PM »
Great work !!!

I am for two. And the price is OK for that quality !


Re: FEELER: THE ULTIMATE Mic-PSU chassis - VINTAGE NEUMANN STYLE!! OPEN!
« Reply #2 on: November 30, 2015, 12:45:12 PM »
I'm in for two as well!

Pip

Re: FEELER: THE ULTIMATE Mic-PSU chassis - VINTAGE NEUMANN STYLE!! OPEN!
« Reply #3 on: November 30, 2015, 01:21:35 PM »
You should really consider a place to mount the resistors on a heat sink. They get hot! Beautiful job!
Pip
New York City
http://geosonixlab.com

rainton

Re: FEELER: THE ULTIMATE Mic-PSU chassis - VINTAGE NEUMANN STYLE!! OPEN!
« Reply #4 on: November 30, 2015, 04:21:30 PM »
You should really consider a place to mount the resistors on a heat sink. They get hot! Beautiful job!

Thanks for your input Pip!   :)
I always used to leave about 1cm between the pcb and the resistors and it worked quite well so far.
A heatsink would be a great add-on but do you have any suggestions on how to include it into the design?

I'm afraid it's a little hard to find a universal solution that fits all possible pcbs, standoff heights etc.
Maybe it's easier to add something like a heatsink individually?

open for suggestions and ideas though

Winetree

Re: FEELER: THE ULTIMATE Mic-PSU chassis - VINTAGE NEUMANN STYLE!! OPEN!
« Reply #5 on: November 30, 2015, 05:32:01 PM »
These look great.
What do you think shipping to the U.S.A. ( 91730 ) would cost?

0dbfs

Re: FEELER: THE ULTIMATE Mic-PSU chassis - VINTAGE NEUMANN STYLE!! OPEN!
« Reply #6 on: November 30, 2015, 05:32:20 PM »
You should really consider a place to mount the resistors on a heat sink. They get hot! Beautiful job!

Thanks for your input Pip!   :)
I always used to leave about 1cm between the pcb and the resistors and it worked quite well so far.
A heatsink would be a great add-on but do you have any suggestions on how to include it into the design?

I'm afraid it's a little hard to find a universal solution that fits all possible pcbs, standoff heights etc.
Maybe it's easier to add something like a heatsink individually?

open for suggestions and ideas though
If the dividing panel was cheese-grater style you could mount all kinds of PCB's, heatsinks, etc without drilling....

I also like the idea of the tweaker pot(s) and test points being behind a screw-out access panel for safety.

I might make the IEC inlet hole the style that allows the fuse to be swapped out without opening the unit.

Cheers,
jb
Music is everything!
Audio is everything else!

rainton

Re: FEELER: THE ULTIMATE Mic-PSU chassis - VINTAGE NEUMANN STYLE!! OPEN!
« Reply #7 on: November 30, 2015, 05:54:11 PM »
These look great.
What do you think shipping to the U.S.A. ( 91730 ) would cost?

The cheapest rate for 1 chassis is a small package which is 19 Euros, but this includes insurance for up to 50 Euros.
For up to 4 chassis it will be 35 Euros including insurance for up to 500 Euros and tracking number.

If there's more interest from several people in the US it might be worth considering to combine shipping from Germany to the US to keep the costs down :)

rainton

Re: FEELER: THE ULTIMATE Mic-PSU chassis - VINTAGE NEUMANN STYLE!! OPEN!
« Reply #8 on: November 30, 2015, 06:26:14 PM »
If the dividing panel was cheese-grater style you could mount all kinds of PCB's, heatsinks, etc without drilling....

I also like the idea of the tweaker pot(s) and test points being behind a screw-out access panel for safety.

I might make the IEC inlet hole the style that allows the fuse to be swapped out without opening the unit.

Cheers,
jb

Thanks jb - good point!
I get your idea :)
But  the dividing panel being made from solid steel is considerably  responsible for the overall sturdiness of the chassis. And adding several different footprints for pcbs is not the problem - it doesn't really affect the manufacturing expenses.
I just need to know the measurement beforehand, so I can include them in the design.
Also -  if going the cheese grater route it's very hard to tell which width of the gaps would be compatible of all kinds of tube mic PSU pcbs...chances are a screw hole sits exactly on one of the "ribs" and then it all becomes a little complicated and less elegant ;)


Regarding the fuse: You actually don't have to open the unit to change the fuse. As you can see in my prototype unit theres a dedicated fuse holder with a small plastic cap which says "fuse". You can just turn the cap and pull it out to swap fuses.
I thought about an IEC inlet hole with integrated fuse holder. That's what I'd usually do in a modern design, but I wanted it to be as close to the original as possible.
The way I did it is exactly how Neumann did it back in the days(same spot, same design).



Phrazemaster

Re: FEELER: THE ULTIMATE Mic-PSU chassis - VINTAGE NEUMANN STYLE!! OPEN!
« Reply #9 on: November 30, 2015, 11:48:45 PM »
Wow this looks absolutely fantastic! If I didn't already have my cases sorted, I would certainly be tempted to join your party!

Nice work!!

Mike
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DerEber

Re: FEELER: THE ULTIMATE Mic-PSU chassis - VINTAGE NEUMANN STYLE!! OPEN!
« Reply #10 on: December 01, 2015, 05:02:45 AM »
I want one :)

I´d take it just as it is. No need for more mounting holes etc. on my side. One could easily drill oneself.
Also Mic PSU is definitely a PTP project for me.

best Stephan

Upacesky

Re: FEELER: THE ULTIMATE Mic-PSU chassis - VINTAGE NEUMANN STYLE!! OPEN!
« Reply #11 on: December 01, 2015, 10:54:02 AM »
I'm in for one

chefducuisine

Re: FEELER: THE ULTIMATE Mic-PSU chassis - VINTAGE NEUMANN STYLE!! OPEN!
« Reply #12 on: December 01, 2015, 12:47:21 PM »
interested in two

Phrazemaster

Re: FEELER: THE ULTIMATE Mic-PSU chassis - VINTAGE NEUMANN STYLE!! OPEN!
« Reply #13 on: December 01, 2015, 01:52:20 PM »
Geez, the quality of items on offer around here just keeps getting better, and better, and better!!!!

Keep this up and we'll have to change the name to GroupDIFY (Do It For You)! ;)

Way to go Rainton. :)
« Last Edit: December 01, 2015, 03:54:46 PM by Phrazemaster »
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mrcase

Re: FEELER: THE ULTIMATE Mic-PSU chassis - VINTAGE NEUMANN STYLE!! OPEN!
« Reply #14 on: December 02, 2015, 08:16:09 AM »
Looking great!
I´m in for one at least. I´d like the binder connector option! btw which amphenol connector were you thinking of? could also work for me... Not so keen on the neutrik one though.

great work!
best,
M

mrclunk

Re: FEELER: THE ULTIMATE Mic-PSU chassis - VINTAGE NEUMANN STYLE!! OPEN!
« Reply #15 on: December 02, 2015, 10:09:34 AM »
Really nice, would be in for two.
 
Btw, i really like the way the collective cases box has the over hang to protect knobs and switches. 
This would make it perfect!

rainton

Re: FEELER: THE ULTIMATE Mic-PSU chassis - VINTAGE NEUMANN STYLE!! OPEN!
« Reply #16 on: December 02, 2015, 05:21:31 PM »
Looking great!
I´m in for one at least. I´d like the binder connector option! btw which amphenol connector were you thinking of? could also work for me... Not so keen on the neutrik one though.

great work!
best,
M

Thanks!
Well I meant the Binder 961 series/the older Amphenol-Tuchel - they both look exactly the same.
Then there's the big old Tuchel connectors like the U47 used it for example. I still have a couple of them here.

My newly designed PSU pictured above houses a 5-pin Binder 961 Series and the Collective Cases PSU next to it houses one of those big 6-pin vintage Tuchel connectors. But they've gotten so very expensive lately...

So I would offer the PSU chassis with Binder 961series cutout on the Mic input side by default, but if there's enough request for an XLR in this spot or even a vintage Tuchel, I would try to figure something out :)

mrcase

Re: FEELER: THE ULTIMATE Mic-PSU chassis - VINTAGE NEUMANN STYLE!! OPEN!
« Reply #17 on: December 02, 2015, 05:34:42 PM »
So I would offer the PSU chassis with Binder 961series cutout on the Mic input side by default, but if there's enough request for an XLR in this spot or even a vintage Tuchel, I would try to figure something out :)

Great! I´m all for the binder connector. It´s the 691 series though, right?

rainton

Re: FEELER: THE ULTIMATE Mic-PSU chassis - VINTAGE NEUMANN STYLE!! OPEN!
« Reply #18 on: December 02, 2015, 05:41:35 PM »
So I would offer the PSU chassis with Binder 961series cutout on the Mic input side by default, but if there's enough request for an XLR in this spot or even a vintage Tuchel, I would try to figure something out :)

Great! I´m all for the binder connector. It´s the 691 series though, right?

oh yes of course - the 691series

edit: if I correct it now, both of our last posts look extremely weird  hahaha  ;D

rainton

Re: FEELER: THE ULTIMATE Mic-PSU chassis - VINTAGE NEUMANN STYLE!! OPEN!
« Reply #19 on: December 02, 2015, 05:45:50 PM »
Really nice, would be in for two.
 
Btw, i really like the way the collective cases box has the over hang to protect knobs and switches. 
This would make it perfect!

Funny - and I always found the Neumann PSU to look far more solid and compact because it doesn't have that over hang ;)