Peerless 10" mid/woofer for two way?

[ivanlukic]

WLM (Wiener Lautsprecher Manufaktur) use 50mm cone tweeter with great success but not with 10". Velvet model use the tweeter from the att. picture.

 

[system7]

A big bass two way is common enough in the loudspeaker repertoire:

The above Celestion Ditton 25 was a derivative of this:
Celestion Ditton 25 help needed

The supertweeter is just a bit of icing on the cake.

I had some fun at the local second-hand shop yesterday. My friend had a pair of old ScanDyna speakers for sale at £400. Why so much? Well, ScanDyna stuff is collectable, he said. The Japanese will pay huge sums for these old retro speakers, which had superb drive units.

I know a bit about this sort of stuff, and told him it likely had SEAS or Scanspeak drivers. He thought it might be a three way. We whipped the grilles off to have a look. I knew what it was straight away. Big 10" bass and a HUGE tweeter with an aperiodic vent.

Do you? Not worth £400 though, IMO.

 

[oohms]

I had the urge to make a 'poor man's A26' using that peerless woofer coupled with a Monacor DT300 + WG300 waveguide but i wasn't sure how good the midrange of the peerless was

 

[system7]

There's a very interesting article about the Dynaco A25 here:
Dynaco Speaker Component Info

How it works with bigger 8-10" cones is there is a near optimal cone damping built in quite often. So they don't have awful sounding breakup even when crossover is close to the first real breakup node, which is around 2.5kHz with a 10" and 3kHz with an 8".

I must have seen all the ways of doing crossovers with these things over the years. Impedance correction, notches around 2.5kHz and even higher to get the higher breakup nodes. Peter Comeau did a mild bass filter for the SEAS A26 (below) even if it didn't strictly need one. The BBC did electronic crossovers in some of their big two way monitors.

This 10" speaker is definitely doable. But personally I think an 8" bass is easier and less demanding on the tweeter while doing much the same thing.

 

[ivanlukic]

But personally I think an 8" bass is easier and less demanding on the tweeter while doing much the same thing.

I agree with you and anatech that 8" + 25mm dome is safe bet. With 10" problems to solve start to appear. But there were successful 10" + tweeter even with 19mm tweeter. One that I know was Tannoy Oxford. But that 19mm tweeter was compression horn bullet tweeter! That loudspeaker was not that much pleasant with every amplifier and with all kinds of music. It was good for pop and jazz, but not for classical.

If you want something inherently musical you need 8" + 25mm dome. It works with all kinds of music. One good example that I remember was Wilmslow Audio kit from the eighties Peerless 825. 8" poly cone with foam surround and 25mm textile dome KO10DT (used in big Tandberg monitors!).

 

[system7]

John DeVore apparently uses a Morel CAT378 in his Orangutan.

Seems to do the right things.

This tweeter has an impressive response on a single 5.6uF capacitor according to our own Michael Chua:

MOREL CAT 378 Soft Dome Horn Tweeter - AmpsLab

As does the SEAS DXT according to Joachim Gerhard:
H1499-06 27TBCD/GB-DXT

Whether you actually want a single capacitor is debateable. I think they might blend in on a smoother sounding 4th order with a flip of polarity.

 

[Juhazi]

I checked some AmpsLab speaker projects. Looks like distortion measurements are done with too low spl, showing practically only ambient noise unless tweeter is very stressed. No directivity measurements either.

 

[system7]

I was doing some modelling last night with Michael Chua's Morel CAT378 FRD and ZMA files, and I really didn't get anything that seemed to fall into place with woofers like the Peerless.

It's a 2kHz crossover, and I seemed to need a notch on the awkward breakup peak around 3kHz. I did get a third order electrical working on the tweeter, which is where I wanted to go. 2kHz crossover? I don't fancy it. Maybe people who listen to grunge metal like this sort of thing.

But really, I think the SEAS A26 woofer is a rather special animal, and a poor man's version is just going to frustrate. I've seen enough here to give up on the Peerless 10" plus big tweeter idea. There's just no point in grappling with the problems when an 8" is just going to work much better.

 

[anatech]

That's my point of view as well.

-Chris

 

[Bubit]

..... if we replace the tweeter with a 2 inch dome (Ciare HM500) + tweeter, the project will become more expensive but will work easy