The Talking Machine Forum — For All Antique Phonographs & Recordings

I have an HMV5 with oxidized cover (a dull grey). I don't know about the reasons for HMV to abandon it, but the one I have is identical to the orthophonic Victor in all external aspects. I have not opened it because it works well. I am sure it has the same pot metal fragility as Victor's, but it does not appear to be any worse, and certainly not more fragile than the 5a and 5b are today. If it was already fragile 80 years ago one cannot tell, but if it were just a case of error in the fabrication of the amalgam, HMV could have corrected it without changing the design to something different. The HMV 4 was made before the HMV5, and most of the production was pot metal with a smaller quantity made in brass (like the Victor 4/4a), so HMV had already experience in producing pot metal soundboxes when it undertook to make the nr 5.

Soundwise my HMV5 is better than all the other HMVs I have (exhibition, 2, 4, 5a and 5b). Evidently the sonic assessment needs to be put in perspective, since all I can say pertains to the particular soundboxes I own, and I would not generalize to say that all HMV5s sound better. I have two 5b soundboxes that look externally identical, but one has a much reduced frequency response in both ends of the spectrum than the other. Why is that I cannot tell.

i have the model HMV 158 with number 16 bronze soundbox and the sound is as good as the 5a and 5b

I like the 16, it is certainly a good soundbox in good condition. This is my video. https://youtu.be/JMn4Vgj3ySk

The 5a was also made in Florentine bronze, for the Automatic models. This was also used on the 152 and 153. The 153 replaced the 158 in 1934, which was also when the No 16 disappeared on the 102.
I have never found any evidence for the reason for (or exact timing of) the replacement of the No 5 by the 5a, but it was clearly very early on in 1928. As the 194 and 203 were not introduced until January 1928, the number of gilt No 5s in existence can only ever have been tiny.

Merry Christmas!