This stereo step up transformer assy. is for use with low output Moving Coil phono cartridges for Vinyl playback. The box uses UTC A10 microphone input transformers. These transformers are connected for 150 ohm primary to 50k ohm secondary that is a perfect match for all normal magnetic phono pre amps 47k ohm w RIAA equalization.
A10's are manetically sheilded in a cast metal case; they are rated for +10dbm maximum input level & are rated 30 to 20khz frequency response at this level. I ran a frequency sweep w a laboratory audio generator They are ruler flat from 60hz to 135 khz with a10 millivot signal level. They are a perfect match for the Denon 103R moving coil cartridge, sound quality is very good.
The avg. output from the Denon 103R is approx. 400 micro volts or 0.0004 vac.
The transformers step that up to approx. 8 milli volts .008 vac. into a standard RIAA phono preamp. These transformers were used in many name brand vacuum tube profesional microphone preamlifiers late 40's to early 70's.
I purchased them new in the late 50's & built a 6 input stereo mixing console
for on location recording of master tapes for several small record labels in the 60's & have been in my posession the entire time.
There is also a ground lift switch to disconnect the transformer secondaries from case ground.
For Salle in U.S. & Canada. $395-
A10's are manetically sheilded in a cast metal case; they are rated for +10dbm maximum input level & are rated 30 to 20khz frequency response at this level. I ran a frequency sweep w a laboratory audio generator They are ruler flat from 60hz to 135 khz with a10 millivot signal level. They are a perfect match for the Denon 103R moving coil cartridge, sound quality is very good.
The avg. output from the Denon 103R is approx. 400 micro volts or 0.0004 vac.
The transformers step that up to approx. 8 milli volts .008 vac. into a standard RIAA phono preamp. These transformers were used in many name brand vacuum tube profesional microphone preamlifiers late 40's to early 70's.
I purchased them new in the late 50's & built a 6 input stereo mixing console
for on location recording of master tapes for several small record labels in the 60's & have been in my posession the entire time.
There is also a ground lift switch to disconnect the transformer secondaries from case ground.
For Salle in U.S. & Canada. $395-
