Telefunken M5A

[Peter Ruhrberg]

I don't know how to check the azimuth (I have to look this up. I have a leader oscillopscope which I think I must use).

If your M5A is a full track machine, you would just need a VTVM or some similar.

You first playback your reference tape at the slowest speed and adjust the playback head azimuth at 1 and 10 kHz for maximum output level.

Then you adjust the recording head in the same way, using a relatively unused tape with the same speed and frequencies (or white noise, if you prefer) at about 20 dB below reference level.

That should be it.

An overview of the expected loss due to azimuth misalignment is given in Robert Morrison's "Standard Tape Manual":

When I play a tape that was recorded on the M5A on my other deck, a telefunken M15A, there is far too much treble. Could it be a worn playback head on the M5A?

This might be an option, but of yourse I cannot know that from a distance.
The first thing you need to do is to make sure first that the azimuth for both heads is correctly adjusted.
(What makes me particularly suspicious in the first place is the level fluctuation you noticed while trying to adjust the bias.)

If this is the case, do you know where I can buy a know playback head or or a all new headbridge for the Telefunken M5a?

Not offhand, but let's first see if a replacement is needed at all.
Perhaps you could take a high-res close-up of the heads?
At least this would make it somewhat easier for me to assess their condition.

Best, Peter

If your M5A is one of these rare stereo versions, the alignment procedure is somewhat different, so please let me know.