Pro vs hifi drivers - pros and cons?

[Pano]

Altec used to list the dynamic range for some of their speakers. A rare thing to see.

Rob. A Farscape & Python fan, I see. Good man!

[mattpwill]

Like here Subwoofer testit - DVD Plaza Forums

Do pro drivers tend to have much lower hysteresis than hifi company (eg Seas, Peerless) drivers? I assume they do, but just thought I'd ask. Thanks

[Andre Visser]

Originally Posted by Robh3606

If you take a 85db speaker move back 12 ft you would be lucky to get 105db from the pair with 100 watts where you listen. That sounds like a rather high SPL level but it's not with a well recorded music where the dynamics are properly recorded. A snare drum rim shot could get you there in a heart beat, even playing at a more modest 85db average.
Rob

I agree but there are also hi-fi drivers with efficiency of 90dB and more. Apart from that, most high SPL's in music are of an impulse nature so the average power on the voice-coil isn't nearly as high as suggested.

[gedlee]

Originally Posted by Robh3606

I think Earls right we need a Dynamic Linearity test to really see what's happening.

Rob

I think that the test protocal is not too hard to develop, I've done that, and I've taken some data. I just need to get the time to analyze it.

Originally Posted by mattpwill

Like here Subwoofer testit - DVD Plaza Forums

Do pro drivers tend to have much lower hysteresis than hifi company (eg Seas, Peerless) drivers? I assume they do, but just thought I'd ask. Thanks

I don't think subs are part of the "dynamics" issue.

What do you mean bu "hysteresis"? in a loudspeaker?

[kevinkr]

Originally Posted by tinitus

Makes me wonder how paper voice coils have lasted through half a century, and are also said to result in very good sound, especially with silver wire

I've had more than a few, none with silver wire, and these particular ones did sound quite good. Most have been rather efficient types with relatively low rated continuous power - within reason I have not noticed thermal compression to be a major issue with them either - but it is easily measurable if you push one of these drivers close to its rated power. I've also burned up a few as well quite unfortunately.. (The saddest of which were some very nice Coral full range drivers that I bought new in my teens - they did not long survive my first 30W per channel stereo receiver purchased a couple of years later.)

[mattpwill]

I posted the link to subs only as an example, because they measure power compression

I'll quote something that explains hysteresis distortion:
Hysteresis distortion implies that the system transfer characteristic is not always singlevalued for a given instantaneous input and will vary with both the change of direction and the level of the input and that it will therefore produce distortion that has a different phase to that produced by harmonic distortion.

Hifi drivers tend to use very lossy surrounds compared to most pro drivers, which I assume introduces hysteresis distortion.

[tinitus]

Originally Posted by kevinkr

but it is easily measurable if you push one of these drivers close to its rated power. I've also burned up a few as well quite unfortunately

Ofcourse they have the low power limits
High sensitivity is essential
Sure, low sensitivity combined with low power handling might be a real problem
Even so, some of those seem to make many people happy nonetheless
Expectations to SPL would be a major player

btw, In my youth I accidentally put full supply power into my Lowther fullranges, due to some amp malfunction
ALL of the voice coil wire was literally thrown out of the gap, in a messed up bundle hanging in front of the drivers
Funny "picture", but it wasnt much fun when it happened
I cant bare the thought of owning the exstremely expencive Feastrex drivers, and always have to fear the moments(rare) with alcohol on the table

[CLS]

Originally Posted by tinitus

...

In my youth I accidentally put full supply power into my Lowther fullranges, due to some amp malfunction ALL of the voice coil wire was literally thrown out of the gap, in a messed up bundle hanging in front of the drivers
...

What kind of amp, and what kind of malfuction?

I've experienced blown tweeter by old leaky filter caps in ancient tube amp. I was in another room and heard suspicious noises, like some muffled fireworks. It was odd that the noise was not loud, and there're output transformer and series cap before the tweeter. One of the tweeter was still blown.

[tinitus]

Originally Posted by CLS

What kind of amp, and what kind of malfuction?

Amp was old SS amp
Malfunction was nothing but a failing fuse, nothing else wrong with amp

[gedlee]

Originally Posted by mattpwill

I posted the link to subs only as an example, because they measure power compression

I'll quote something that explains hysteresis distortion:
Hysteresis distortion implies that the system transfer characteristic is not always singlevalued for a given instantaneous input and will vary with both the change of direction and the level of the input and that it will therefore produce distortion that has a different phase to that produced by harmonic distortion.

Hifi drivers tend to use very lossy surrounds compared to most pro drivers, which I assume introduces hysteresis distortion.

I knew what hysteresis was, I was questioning why you thought such a thing existed. To the best of my knowledge this is not a significant factor in any loudspeaker that I have ever seen.

I am not even sure that I could design one that had significant amounts of hysteresis let alone it happening naturally.