A Meter bridge too far.

I do like the clean simplicity of the aesthetics of my Mission Cyrus One amplifier.

Meter Bridge
Meter Bridge

However a nice big pair of mechanical VU meters also looks good. So, I built this.

The donor was a Technics 616 cassette deck which was a bit tatty and had a horrible electronic problem that I had grown tired of trying to trace.

Technics meters
Technics meters

I stripped it for parts, salvaging the mechanism, motor and this marvelous pair of VU meters.

The hardest thing to get right was the enclosure. I tried various plastic project cases but the right size and proportions were elusive. It was also difficult to accurately and neatly cut the required rectangular holes for the meters.

The solution is actually a £2 wooden box from the high street budget bookshop “The Works”.  The thin wood could be cut with a sharp scalpel, using the original Technics tape deck panel as a template.

Meter in the dark

The wood is protected by a couple of coats of Ronseal varnish (it does what it says on the tin) and it is also painted black on the inside using games workshop “chaos black” aerosol. This is necessary to prevent bleed through of light from the meters bulbs.

Bare light bulb
Bare light bulb

The black paint was not sufficient to prevent the bulbs from shining through the wood. I solved this with copper foil. This stuff is sold for shielding the electrics inside the wooden cavities of electric guitars.

Shielded light bulb

Here we see it stops the light and has the added bonus of reflecting back with a nice golden hue for a great vintage look.

VU meter driver module

Drive electronics are courtesy of a module, £9 off eBay. A a pair of RCA phono sockets are provided to facilitate easy insertion in the signal path, usually in the amplifier tape loop. Power is from a 12 volt plug top power supply.

Meter size compared

These meters are big. 3 inches in diameter. Even my huge Sony tc-377 open reel deck only has 2 inch meters. The unit sits on top of my system and looks the business.