Absolutely!

I doubt that the horn has much to do with it, it just limits frequency response at the top and bottom end due to limitation in throat size and acoustic impedance coupling between the horn mouth and the cutter. When bandwidth limited the spectral responses of instruments and voices on electrical recordings show very little difference compared to their acoustic counterparts. Time-dependent effects in systems such as this are relatively trivial to resolve by means of deconvolution; division of the signal by the transfer function (a mathematical model of the horn and cutter) of the system in the frequency domain (within sensible bandwidth limits of course) and inverse Fourier transformation (to recover the signal minus the effect of the recording system) would accomplish this to a reasonable extent and give a good indication of any spurious effect that the horn has. It would be impossible to recover any recording equipment of the time used in these sessions; recording companies were extremely protective of their equipment, you never see a cutter in photos of old studios, only the horn. When they switched to electric recording systems, the cutters would most likely have been adapted for electrical use or destroyed.

Undoubtedly the bandwidth limiting of the horn #markboyle9941 affects our perception of the voice - just as with AM radios etc. Finite horns, however, have quite uneven impedance and the phase-frequency response can have severe anomalies (kind of like a comb filter in appearance). That is, I guess quite easy to reproduce nowadays digitally and compare the sound with and without it. I agree with what you wrote regarding the time-domain but I am not sure whether the back wave introduced by the horn does not create some sort of standing wave which in combination with the impedance anomalies would make it harder to undo. We must also not forget that the original sound from the orchestra was not limited in bandwidth. If we knew the original horns dimensions though, things would be simpler. The other thing to remember is that the wave front of the sound reaching the horn when recording is curved the opposite way than that of the sound coming out of the horn when the horn is reproducing. I have no idea of what the horn model is when driven by sound coming from a point source and going into its mouth although I guess this could be modelled as some sort of time-dependent effect, at least for the singer who I think was always sitting in front of the horn's mouth. Maybe the orchestra, sitting a bit further back could be approximated as a plane wave. That would probably be a gross approximation as I think the instrument players were also huddled together as close to the mouth as possible although I'm not sure what the process was when recording large orchestras.

It's an ARB 12" unipivot (rigid carbon fibre armwand). The "bit too much" between the cartridge and the headshell (although it isn't really a headshell) is a Deccapod (Decca made them). It *is* a custom cartridge housing that is designed to absorb excess vibration that would normally be damped by a cantilever in an ordinary pickup. Decca cartridges need mass as well, hence the heavy steel cartridge carrier. There is no compromise in geometry here, the VTA/SRA (critical for Decca alignment) are correct as is the alignment geometry (Baerwald is used in this case). The cartridge sounds fine, I never have problems with poor tracking using this setup as long as the records are clean and in good condition.

I'll have to check this out #markboyle9941 - I have never heard of ARB before. It looks very well made though. I always wondered about the soft plastic used in the Deccapod and the cantilever-type construction of the contraption which seems to give it a lot of compliance. Thanks for clearing this up. The geometry I was referring to was not to do with alignment but with the dynamic behaviour (stability) of the arm on the vertical axis when balanced. Effectively the stuff between the cartridge and the headshell makes the arm slightly longer. I guess that's trivial. That the weight of the cartridge sits lower than it would with a normal cartridge I guess is compensated by the arm's counterweight already sitting quite low itself. It also decouples the cartridge and introduces more compliance but I guess that, in the case of the Decca, this is rather desired although t cannot help thinking it would introduce smearing. Anyway, I have never used my modern Decca so I cannot know. I have a couple of older Deccas but there is something wrong either with the cartridges themselves or the adapter because I get only mono (one channel) out of them so I have not listened to them much. I hope to fix this one day.

I cannot find anything about the unipivot on the internet #markboyle9941 . He currently has a dual pivot on ebay though which looks interesting. I cannot find an ARB website either.