Philips speaker nomenclature, AD and ADZ

[jamesjung21]

Hi all

I noticed that a few vintage Philips full range speakers have part numbers starting with ADZ instead of usual AD (e.g. ADZ XXXX AM).

Does anyone know what the prefix letter Z mean?

Kind regards,
James

[jakeb2]

Text in a Dutch paper: "luidspreker met verhoogde gevoeligheid in het frequentiegebied met 3000 Hz als middelpunt". I Will try to translate to English...

Drivers with higher sensitivity in the frequency around 3000 Hz (3000 Hz as center)

[jamesjung21]

Thank you jakeb2.

I wonder what the significance of that is? For comparison, I have seen a 9710/M8 response curve and it has higher sensitivity at 8kHz.

Kind regards,
James

[Steerpike]

According to my Philips databook, Z as a suffix denotes a notably higher response around 3kHz (such as used in portable equipment for voice reproduction), while M denotes a smooth and extended frequency response (typically dual cone full range).

Z in the prefix area is not described.

[InclinedPlane]

3khz? Aha! That would be the model with 'more cone breakup'.

[jakeb2]

@Steerpike, you're right. 'Z' as a suffix. Sorry topicstarter.

According to the paper useful for smaller amplifiers, small radios, intercoms and car radios. There's also a 'Y' which Philips recommends for these applications. A higher sensitivity at 2000...6000.

Here's the paper I downloaded from Internet a while ago. I think from mfbfreaks : Official Site, but I'm not sure.