Where to get chassis for monoblocks?


Hi guys,

I have been going slightly mad (hello, Freddie!) looking for chassises for my monoblock amplifiers (x4) project.
I am basically looking for a 12" (Wide) x 17" (Deep) x 8" (High), aluminium box. As I am only looking at 4 pieces to be made, most places don't give me the time of the day.

I don't mind paying as much as $200 per box if it can approach the kind of quality Mark Levinson/ Krell stuff come in. Anyone know of links?

I am not schooled in CAD, so I am going to draw up a few templates, and make an exact mock-up with (very thick (1/8" plasticized cardboard). Do you think, with this, the machine/enclosure shops would be more inclined to make the chassis?

Thank you!
atzen811
Sorry to get off topic but, have you any plans for a line stage? I have no technical ability, but a simple idea that might work?
The second time around.
Try Horace Atkinson. Nice work too.

e-mail: hatkinson@hot.rr.com

I think there is some info on Horace at the Headwize site.
Well, for the curious few... if any...
here are the dimensions (to be duplicated in quad for 4 monoblocks):

12" x 15" x 08" (W x D x H) Flat enameled steel
(Not including face plate)

Top panel thoroughly vented.
Both side panels thoroughly vented.

Faceplate: thickest aluminium panel you have got (preferably 3/8" or more), anodized black. Dimensions 10" x 14" to be mounted to chassis.

Rear panel will have 2 punch outs.
Cut-out 1: IEC connector
Cut-out 2: 3.3" x 7.9" (for heatsink)

Cheers,
For a small run (4) of custom steel & aluminium boxes with venting on the top and sides and a finished faceplate expect to pay alot more than $200 per chassis. The tooling and finishing is quite time consuming and the labor alone could cost $200. Krell/Levinson chassis are WAY more complex and expensive then what you have in mind and would probably sell for more than $1000 (with no amp of course). Your best bet would be to find a pre-fabricated chassis that is close enough to what you want and then modify that.
Hi Atzen,
I have four chassis available from an old project a few years ago that might be of interest.

I was building the Pass/Thagard A75 Class A solid state amps in monoblock versions. I have a set of detailed design drawings that I can FAX to you. The chassis are substantially strong to carry the heavy weight and look very professional like those of KRELL or Threshold. These were custom manufactured for me to my specs by a professional electronics enclosure fab shop in Toronto.

Brief description:
a) Ventilated "U" shaped chassis formed from 12 gauge steel (0.109" thk)measuring 10"W, 20"D and 8"H. Sides are drilled for mounting heatsinks and for wiring of output devices.
b) Ventilated top cover (3 rows of slots, 1/8" X 1" long at 1/4" centers made from 12 gauge steel. Appearance is similar to those on Krell "S" series amplifiers.
c) 12 gauge steel rear panel with cutouts for two 5-Way binding posts for bi-wiring of speakers, 3-pin XLR female balanced input connector, RCA input connector, two fuse holders and (20 A I think)IEC detachable line cord.
d) All steel enclosure parts are cleaned and painted with textured (spatter)satin black enamel.
e) Front panel 19" W X 8-3/4" H X 3/8" thk aluminum (Not yet anodized or machined)
f) Two heavy duty rack handles sculptured from 1" X 1-1/2" alumium bar (Also unfinished, looks like old Threshold)

Let me know if interested.
Regards and good luck.