Page 1 of 2

Tweeter differences

Posted: Fri Sep 03, 2021 8:22 pm
by Daniel Quinn
Now it will come as no surprise that I think most equipment differences in hifi are illusions to sell you something.

I've been looking at tweeters . In particular scan speak tweeters and what makes them different. If you look at a tweeter , there isn't a lot to it. A membrane with wire and a magnet .

I've got a pair a £79, £130 and £210. If you look at these 3 models they what appears to be the same magnet. Therefore the only difference is the membrane.

The higher up the price range , the thinner more tranlucestant the membranes becomes . I regret to say it is audible in isolation. The higher priced the better .

When you add in the bass driver and midrange the difference becomes less palpable so much so the jury is still out.

So the differences are real , worth the price , no , but what can you do.

Re: Tweeter differences

Posted: Fri Sep 03, 2021 8:50 pm
by Geoff.R.G
I would be surprised if the coils were the same, or the suspension or even the magnets but the differences may be small and subtle. Alternatively they are all identical but with different badges. I would expect, in a commercial product, the crossover to make more difference.

However, if you can hear a difference it must be there so the next question is what causes it?

Re: Tweeter differences

Posted: Fri Sep 03, 2021 9:51 pm
by Daniel Quinn
Coils are simply copper wire attached to the membrane.

Tweeters don'ts have a suspension ? Membrane with could attached fits in to the magnet. Precisely were is the suspension?

The difference is the membrane. Are you drunk? The expensive membrane is lighter and able to react faster.

Re: Tweeter differences

Posted: Fri Sep 03, 2021 10:39 pm
by r3xj0hn570n
There are differences inside.

The tweeter suspension is clearly between the top of the voice coil (where the dome is glued on) and a carrier that is screwed or clamped to the magnet. They are usually made as an extension of the dome (in soft dome tweeters, and in the case of JBL titanium dome too).

Other differences are the shape of the magnetic field, better tweeters have a more symmetric and linear field within their xmax. Some have hexagonal or ribbon wire in the voice coils to pack more copper in and make the coil more compact, so the gap can be reduced. Some have copper clad aluminium to decrease weight. Many have drill pole pieces to lower Fs and make it easier to design the crossover. Some domes are made of vapour deposited carbon (diamond-like). Eeek.

That said, scanspeak tweeters do seem very expensive for what they are. There isn't a lot to them, no matter how well they are designed.

Re: Tweeter differences

Posted: Tue Sep 07, 2021 11:12 am
by Daniel Quinn
a scanspeak tweeter is made up of two elements. the membrane with voice coil attached. The magnet.

1. where is the suspension, what is it made of?
2. are you saying the voice coils (essentially copper wire) are sufficiently different to effect the sound if so how?

Re: Tweeter differences

Posted: Tue Sep 07, 2021 9:00 pm
by Geoff.R.G
Daniel Quinn wrote: Tue Sep 07, 2021 11:12 am a scanspeak tweeter is made up of two elements. the membrane with voice coil attached. The magnet.

1. where is the suspension, what is it made of?
2. are you saying the voice coils (essentially copper wire) are sufficiently different to effect the sound if so how?
I am not familiar with the Scanspeak tweeter so I can’t comment on the suspension

The coil in any speaker will be optimised to the physical characteristics of the magnet and diaphragm. The designer may opt for copper or another material such as Aluminium, Silver or some alloy. The shape of the windings may be round, rectangular, hexagonal or some other shape. The gap between the poles of the magnet may be small and deep to allow for longer travel or wide to allow a heavier winding to generate more force to move the diaphragm. The force required will depend on the stiffness of the diaphragm and/or the suspension.

It will also be necessary to consider the frequency range that is to be covered, the desired impedance, the DC resistance and the inductance of the coil. The strength of the magnet will also affect the design of the coil.

I am not speaker designer and it has taken me only a few minutes to come up with a range of factors that may affect the designer’s thinking. I am sure someone with greater knowledge will be able to add others. He/she will have reasons why particular features have been employed and what effect various changes may have on the eventual sound.

Re: Tweeter differences

Posted: Tue Sep 07, 2021 9:05 pm
by Geoff.R.G
Daniel Quinn wrote: Fri Sep 03, 2021 9:51 pm Coils are simply copper wire attached to the membrane.

Tweeters don'ts have a suspension ? Membrane with could attached fits in to the magnet. Precisely were is the suspension?

The difference is the membrane. Are you drunk? The expensive membrane is lighter and able to react faster.
The weight (mass) of the diaphragm (membrane) may be small compared to that of the coil and former but it is the combined mass that affects how the tweeter behaves. You can’t move the diaphragm without the coil and former so they cannot be discounted.

Re: Tweeter differences

Posted: Wed Sep 08, 2021 8:56 am
by Daniel Quinn
I'm sceptical of anything I read. I prefer empirical experience.

Re: Tweeter differences

Posted: Wed Sep 08, 2021 10:39 am
by CycleCoach
I'm suffering a logical disconnect here.

Didn't you say you heard a difference?

Maybe you need to do some more research?

Re: Tweeter differences

Posted: Wed Sep 08, 2021 12:11 pm
by Daniel Quinn
Please keep up.

I put differences down to diaphragm material.

It was suggested I was wrong or mistaken

I'm exploring this possibility.