Dynaco A25 / M25X Tweeter upgrade question

[TellMeWhy]

I have been using and enjoying these funny Dynaco's or Scan Dyna A25 / M25X hybrids (whatever they are) and whilst the sound is good, am toying with the idea of swapping the 2 small Peerless drivers out for a single tweeter, either the original SEAS H087 or perhaps the new equivalent Seas Prestige 27TFFC (I have read that the 27TFFC is an improvement in most respects).

My question is regarding the crossover capacitor when using a Scan Speak woofer as below. You can see at present the Peerless mid and high units are fed by 2.5 uF and 1.2 uF capacitors (not sure which is which though without checking).

If I were to simply wire in either of the above SEAS tweeters with the Scan Speak woofer, would this require the 5uF or 8uF capacitor?

Can anyone explain what's going on in the wiring of the crossover as it stands?

Anyone got any comments (good or bad) on the idea in general?

All the best from Berlin,
Jon

 

[ivandezande]

You would need crossover designing software of some sort and the T/S parameters and frequency response of both drivers to make an educated decision.

Playing with different drivers/crossovers in premade speakers is never, never worth it unless you have a lot of equipment and knowledge.

 

[TellMeWhy]

You would need crossover designing software of some sort and the T/S parameters and frequency response of both drivers to make an educated decision.

Playing with different drivers/crossovers in premade speakers is never, never worth it unless you have a lot of equipment and knowledge.

But as the original A25 only has a single capacitor crossover, my thought was this would be very simply done!

 

[WaynerN]

The A25 had a simple 5uf cap in series with the tweeter, nothing on the woofer. The A25XL had an 8uf cap in series with the tweeter and an inductor across the coils of the tweeter.

 

[SOTA]

That looks very similar to my A35s.

 

[GeirH]

The A25 and A25XL has different tweeters (Seas 87H and 86H respectively), and a different switch (5-way and 3-way), so choose your crossover accordingly. The A25 crossover schematic looks like this:

You'll find a photo of the A25XL crossover here.

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