About the Transfers
Transferring a transcription disc is a bit more involved than recording a more modern lp record to digital.
The records themselves are 16" across (rather than 12", like an lp) and require a turntable with an arm long enough to accommodate the disc. I used to own a Gates turntable with a 16" Rek-O-Cut arm originally made for radio stations in the 1950s. The table was hefty and an interesting conversation piece, but had a lot of rumble and required some tweaking to get decent results.
For all the transfers you'll hear on the blog, I'm using a Transcriptor II turntable from KAB. It's a modern stock Vestax BDT-2600 that's been modified with a longer arm. The BDT-2600 is a good mid-priced audiophile belt-drive table, so it's capable of very good audio reproduction.
Next, after you've got the right turntable, you need to reproduce the transcriptions with the original equalization curves. Records, due to their very nature, produce scratch and distortion, so, when they're recorded, an equalization curve is used to emphasize and demphasize certain frequencies to minimize noise. The RIAA, in the 1950s when they were a standards body and not hunting down music pirates, developed the curve that we still use on records today.
Before the 1950s, however, it was "anything goes". Record manufacturers had their own curves for 78 recordings, each with advantages and disadvantages. To reproduce 78s or broadcast recordings from the pre-lp RIAA curve era, you need a parametric equalizer that can reproduce the curve used when the disc was made. The most common are called "NAB", developed by the National Association of Broadcasters, and Orthacoustic, developed by RCA, but there are others and some discs, such as those from the Armed Forces Radio Service, include segments with different eq curves.
For equalization, I use a vintage 1970s SAE parametric equalizer on the signal as it is recorded to an audio cd, which I use as my "master" digital copy to create mp3 files for the site.
Oh, and lets not forget needles. Transcriptions were recorded before the lp era and use a wide groove, similar to those used for 78s, so they require a larger needle to properly ride the groove. There were variances in how discs were cut over time and some have damage, so you need to find the right size of stylus that best fits the groove and reproduces the least amount of surface noise. Currently, I have over a half-dozen different styli in my arsenal, with some used for discs with different types of groove damage or odd discs (such as metal based recordings or vertically recorded material) that were only used for brief periods. I use a mix of Grado and Stanton 500 series carts on my turntable; the Stanton can track a little heavier and is useful for warped discs.
After a master is made on audio cd, the material is ripped at full quality to a computer and I use Audacity for minor editing - taking out "skips" or "stuck" grooves, joining sides, trimming the beginning and end of shows, and sometimes minimizing more aggravating pops and ticks. I don't do much filtering on the files - often digital filters can introduce their own problems to the audio - but do use click reduction on some records if they're heavily scratched.
A full quality .wav file of the edited versions of the shows is donated to the Old Time Radio Researchers group for their collections, with many of their shows available at archive.org. For the blog, the files are reduced to 32 kHz mp3 files - this bumps down the quality a bit, but allows for a balance between download times and available server space for the blog.
Transferring one 15 minute show (one side of a 16" transcription) to digital, editing it, and prepping it for the site can take about an hour, particularly if you have to play with different styli, do speed adjustments on the turntable before recording, or have to heavily edit because of skips or stuck grooves.
And that's how the shows are resurrected for streaming through the ether of the Internet...