I dont know if this has been discussed before but its news to me. I was Just browsing the Rangemaster site and came across this on bold red print:
"We are offering a new HiFi option, here are some specs:
A standard Rangemanster will be pretty flat at the higher freq up to 20KHZ Pretty flat down to 100HZ. Below 100Hz the response drops linearly about -3DB when it gets down To 20 HZ. Not bad, that is about half voltage loss. But this can be made up in audio processing. Or there is a Bass boost on board that can be used.
Note that some Rangemasters have been shipped with some HiFi parts in The past already. In just part of the board, not a full HiFi upgrade as I am doing now. Some parts are only now available (or I have just found them).
The low freq respose will be better on these boards These board have a yellow transformer as the small transformer, not blue. Blue is the standard. The large transformer is the modulation transformer and has always been red. The new HiFi modulation Transformer is white.
The new parts: Using the new parts instead of a 3 Db los on the way down from 100HZ To 20 Hz the loss would be about half or 1.5DB I believe that is about a 18% voltage loss. At 10 Hz the loss is 1.2 Db, about 14% voltage loss.
Note that these measurement were made here in my shop with a scope and are not certified."
https://www.am1000rangemaster.com/audiochain.html
Based on the internet Archive he had added this information back in October 2019. I'm not sure which revision I have but it's at least 10 or 15 years old now. Who's familiar with these mods? Anyone with before and after versions (since 2019)?
That's interesting @richpowers. I bought my AM1000E from Keith in 2017. My modulation transformer is blue. I've been thinking about purchasing some more frequency modules from him in the New Year. I wonder if he'd let me also purchase the newer white transformer from him and any upgraded associated parts, or if he'll insist on me sending it back to him for the upgrade. I don't want my transmitter to be off the air for longer than is necessary. The difference in low frequency response doesn't sound that great though.
Sounds as if you have the older version too.
..... The difference in low frequency response doesn't sound that great though.
But Isn't that where the bass is?