Voltage multiplier vs transformer for preamp HV power supply

[frickecello]

Hi forum,

I am deciding between using a voltage multiplier or a small transformer for a tube preamp's HV power supply, the preamp uses four ECC83's and require less than 5 milliamps to operate at about 300V.

The circuit features some op-amps so apart from HV it requires a bipolar supply for them and proper voltage for heaters. I plan to use an AC wall-wart which voltage I can select to use with both the heaters and op-amps (and for the voltage multiplier as well in case I decide to use it).

I'm not sure what to use to get HV, space is a limitation, so what would be the best solution a transformer or a voltage multiplier? Talking objectively is there a difference in sound quality between them?

Thanks in advance,

Mark F.

[Matt.B.H.]

I guess you want to use something like a 9V wallwart type thing and rectify and regulate for DC heaters and positive op amp supply. Negative supply for the op amps could be from a charge pump IC like the MAX1044 and the HT could be from something like this:

http://www.ledsales.com.au/kits/nixie_supply.pdf

You can up the voltage fairly easily by using a UF4007 and a slightly larger choke and play with the switching frequency to compensate. Will have to play with the voltage divider on the output to get you there and also make sure the caps and mosfet can take it.

Here is another one using the MAX1771, better performance but way pricier:

Nixie HV Switching PSU

Also try searching nixie supply on ebay.

Cheers Matt.