Mix bus transformer and summing box with Filtek DV1175 with demo #2

This is the listing for mix bus transformer which is in essence the passive summing mixer built with fine 1% precision metal film 10 kOhm resistors and followed by classic transformer balanced amplifier in eurocard format.

Summing amplifier card is Filtek DV1175 with Haufe transformers and firm SSL sound. The amplifier was recapped in 2024.

You can use it as:

- mix bus transformer to imprint transformer sound in your mix and reduce the amount of compression you want to put on the final mix. Perfect for digital recordings made ITB to process it through analog gear at the end after DA converter.

- summing box to sum up to 8 busses (drum bus, bass, vocals, synths, guitars, orchestra, what else... 8 balanced stereo busses is probably enough in most situations). It is not 16 channel mixer, it is 8 stereo busses summing.

Modern ITB workflow is the perfect source of stems to sum them up and master then.

Chassis donor is Digidesign888.

Outputs are transformer balanced.

The gain of the channels can be set internally up to the level you expect to gain stage the whole mix further (see photos).

The "stompbox" button at the right is for engaging meters built around LM3915, which are considered more as "for fun" rather than real level metering, for two reasons:

- meters are connected to the outputs when the button is engaged and that can influence the sound, even adding some noise while using not properly filtered external PSUs.

- you can calibrate them internally and switch indicator mode with the jumper (see photos), but their visibility is rather limited anyways.

So using "stompbox" button is exactly where it fits - as an effect, added to make these processors less black boring boxes, which I really recommend disengage during mixdown sessions!

Works perfectly from linear PSU at min 15 - max 24 DC Volts. There is standard 5.5/2.1 PSU plug input at the back, so you can find the PSU you need with the voltage you want. Voltage is practically a headroom here.

You can find the demo comparison of similar boxes including listed on youtube @HappinessMastering.

There are boxes, built around different summing amplifiers like Filtek DV1175, Delta V1072D-0, Hensmann CH2242, and so on. I rarely see this kind of comparisons, so highly recommended to watch!

The eurocard 31 pin connector description added, just in case you want to modify something (see photos).

Enjoy!

ATTENTION!

I would like to not ship to far from Netherlands, to countries: Hungary, Romania and Bulgaria as this is expensive and provided addresses are usually not reachable. Please, consider this on order!

No returns.