Vox VBM-1 Amplifier KAT Speaker Modification

Knight Audio Technologies (KAT) has developed a “drop-in” speaker upgrade for the popular, discontinued Vox VBM-1 Brian May Special amplifier. It costs £35.00 + shipping direct.

An alternative upgrade option which some people have carried out involves buying a Dai Ichi brand DC65-30 speaker (still available from Wagner Online in Australia at the time of writing) and fitting a 390 microH 1.3A ELC16B radial inductor (choke), RS part no. 6755576 and a 2.2 microF capacitor, RS part no. 7270473.

However, this original option is ultimately more expensive and involves soldering. Check out the product on the KAT website and view the straightforward installation video on Nigel’s YouTube channel.


Text from the KAT website:

“This is a brand new speaker/filter combination enabling VBM-1 users and Deacy Amplifier-style project builders to get their amps closer in tone to the real Deacy Amp.

The KAT DSP 6.5 TC has been developed primarily as a replacement for the Celestion G6 unit that is sadly no longer in production. It has an on-board filter network that tailors the frequency response to give the full-bodied mid range tones of the real Deacy but without the HF ‘fizz’ that seems to dominate most 6.5″ twin-cone drivers.

A by-product of this development was the realisation that this unit could be dropped straight into the Vox VBM-1 giving immediate results. The Vox VBM-1 is a great amplifier, but, it is a little let-down by its stock speaker unit that tends to suck-out the precious mid range tones and enhance the unwanted high frequency ‘fizz’. The KAT DSP 6.5 TC is a straight swap-out with the stock VBM-1 unit with no soldering required to undertake the works. Just 11 screws and 6 minutes will have the works completed and the tone of the amplifier improved many-fold!

The KAT DSP 6.5 TC can also be used in your own Deacy amplifier-style projects to give your amplifier that great Deacy ‘honk’!”