09-16-2013, 10:51 PM
As Brenda said, there should be no problem with not having the load of the parallel field coil. In fact the set should work better without the extra load on the power supply.
Keep in mind the same tubes would operate with a 250 v supply in a transformer set, so if your DC supply voltage goes from 120V to 130V all the better as to performance. You can always run the set on a variac and confirm that the tubes are operating within ratings as you bring up the line voltage.
I would not be too concerned as to the actual match between the voice coil and output transformer. Its really not that critical. Most speakers from the mid 30's to early 60's were 3 to 4 ohms, so the replacement probably is close to the original.
Keep in mind the same tubes would operate with a 250 v supply in a transformer set, so if your DC supply voltage goes from 120V to 130V all the better as to performance. You can always run the set on a variac and confirm that the tubes are operating within ratings as you bring up the line voltage.
I would not be too concerned as to the actual match between the voice coil and output transformer. Its really not that critical. Most speakers from the mid 30's to early 60's were 3 to 4 ohms, so the replacement probably is close to the original.
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