Hi Cafe Latte,
If you have absolute pitch and you listen to records made before about the late 1920s the lack of variable speed may bug you. After the advent of electrical recording, lathes were driven with AC synchronous motors so "78s" cut in the US (60 Hz) should be 78.26 RPM and those cut in 50 Hz countries should be 78.95 RPM so your turntable should be fine for any electrically recorded 78 RPM record.
For "modern" (after the late 1930s) 78s RIAA is acceptable as they had some sort of eq. Of course the ability to select the eq is best.
Some folks insist that mono records (Lps as well as 78s) are best played with mono cartridges. I can't say that I'm a member of the converted in that belief yet but what I will say is that summing your cartridge output to a single channel makes a vast difference. It is best to do the summing before the eq to get more accurate summing.
I built a mono preamp which sums the channels, selects the high frequency rolloff, bass turnover, and switches from vertical (Edison, Pathe) to lateral recording. I'll link a photo of it.
I see that you build tube amps so I am sure you can build it for ~ $100.
If you want to build one for youself I do have an electronic copy of the schemo I can send you. If you lay out a board and want to sell them we need to talk.
Be aware that it uses solid state op-amps instead of tubes. I love my tubes, but doing this in tubes was more of a project than I was ready for at the time.
Phil
cafe latte wrote:As many know I am doing up a Commonwealth electric which will play 78s, but the 78 speed is not variable, and to be honest I did not know that it would be an issue. I started buying some 78s a few months back as I want to hear them also, when my TT is plinthed up with an arm

A few noob questions , well noob to 78s anyway

How long does the safire tip 78 stylus last?
Do you play through a regular riaa preamp, or is it better to build one for the 78s?
Part of me is wondering if it would be easier to get a gramaphone as a friend of a friend in Leeds I was once introduced to had one with doors with which you controlled the volume and it sounded amazing and the needles were cheap, but apparently they only last a couple of sides.
Regards
CL
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