Faced with a similar dilemma I decided to try something radically different while I arranged for a rebuild of my Proteus and ordered an SPU Royal N. My tone arm allows some flexibility of effective mass by changing the material of a sub plate on which the cartridge is mounted. I could go from 13g with aluminium to 18g with brass, with the weight of the cartridge, its adapter and screws this gives 35.5g against the cartridges compliance and it seems to be enough for decent bass performance. Ortofon’s own arms have an effective mass of between 3 and 5g without a headshell and a G series SPU weighs 30g so they would play in the same region. If you know the weight of your headshell you can work out if your Jelco will give an SPU a decent ride.
What I did find is that once aligned an SPU with a replicant stylus is a very enjoyable cartridge, to the point I’m not sure I’ll keep the Proteus, but I will send it to Ana Mighty Sound and try the result before deciding.
An SPU Royal GM is the equivalent pickup head to the Royal N, it will be at the limit of your arm’s antiskate adjustment according to the numbers but I found the the Royal N didn’t need nearly as much as the 3g VTF would suggest.
Thats only one option of course, there’s a lot of cartridges out there, If my phonostage could take the output level I’d have been tempted to try an EMT but even a standard Lyra is above optimum.
Meanwhile investigate a Lyra rebuild, I don’t know the US situation but in the UK they don’t charge as much as some other makes and they will upgrade to λ spec, you might even be able to opt for SL but that is a guess.
