I need some techy help in order a preamp--resistor values.

Jb, just FYI, the Modwright has a built-in remote volume control that is smooth and quiet, and raises (or lowers!) the volume in small enough increments that won't aggravate you with too large a jump in volume.

Dan

Thank you Dan!

I can’t find any specs on the Elekit’s gain. I’ll email them.

Power amp gains are often not specified, but they can be calculated from the specified maximum power capability and sensitivity numbers (assuming those numbers are reasonably accurate, of course).

Also, in the case of a tube amp having multiple output taps the gains of the different taps will not be the same.

In this case there are two taps, one designated for 4 to 6.3 ohm loads, and one designated for 8 to 16 ohm loads. The specs you provided don’t make clear where within each of those impedance ranges the 9.2 watt maximum output capability occurs. But given that the specs shown here indicate 9.2 watts into 8 ohms let’s assume it occurs at 8 ohms if the higher impedance tap is selected, and at 4 ohms if the lower impedance tap is selected.

Also, in this case it appears that sensitivity (i.e., the input voltage required to drive the amp to its rated maximum output) is being referred to as the "rated input," spec’d at 320 mv.

For the higher impedance tap:

9.2 watts into 8 ohms corresponds to about 8.58 volts.

8.58 volts/320 mv = a voltage gain of 26.8 times = 28.6 db.

For the lower impedance tap the gain would be around 3 db less than that, or about 25.6 db.

As I indicated those numbers could be a little different depending on the specific load impedance upon which the 9.2 watt figure is based. But given those results it’s safe to assume that the gain is fairly typical for a power amp (that in the majority of applications would be used with an active preamp), but is around 10 or 12 db less than is typical for an integrated amp. I would be concerned about that mainly if you are using a vinyl source.

Good luck. Regards,
-- Al

jbhiller

The Khozmo is a great passive, to mate it properly you’ll need the source that ’s feeding it’s input to be at least 500ohms or less in output impedance.
Then order a Khozmo 10kohm series/shunt, this will then also be a great match into your 50kohm input impedance Elekit amp which is as you stated 0.32v input sensitivity

BTW Elekit made good stuff, I've got one of their preamps here, and was impressed with quality of the kit and the sound. Still nowhere near as dynamic or transparent as a properly mated passive.
 
Cheers George