Pro vs hifi drivers - pros and cons?

[thoriated]

The discussion on this thread proves it too when we have post talking about outdated processing like AC-3 thinking its the only option

I presume you refer to Marcus76 here. I have had a DTS decoder for years, not to mention my DVDA & SACD capable DVD players. Then there's my BD player.

[tinitus]

Originally Posted by 45

Its not about level it's about dynamics.

I take it that includes definition as well

But sure, if definition is lacking louder SPL usually helps getting in some of the excitement, and some beer as well
But it only lasts until ears and brain give in, turning down hearing sensitivity, or when drinking supply runs out

[kevinkr]

Originally Posted by tinitus

I take it that includes definition as well

But sure, if definition is lacking louder SPL usually helps getting in some of the excitement, and some beer as well
But it only lasts until ears and brain give in, turning down hearing sensitivity, or when drinking supply runs out

Seriously I think that largely holds true when you push the average Spl level to the point where your hearing threshold starts to reset. I hardly ever listen that loud these days... Pass the beer...

[markus76]

As 45 said, dynamics is important. But how dynamic is a driver when its voicecoil starts to glow like a toaster while playing music at 70dB SPL (listening position)?

Hope this post was on topic - don't want to be locked up alone with 45 in the Sin Bin

Best, Markus

[Andre Visser]

Originally Posted by markus76

As 45 said, dynamics is important. But how dynamic is a driver when its voicecoil starts to glow like a toaster while playing music at 70dB SPL (listening position)?

Do you have data to support that?

Voice-coil temperatures.

[gedlee]

Originally Posted by Andre Visser

Do you have data to support that?

Voice-coil temperatures.

To quote from the paper that you referenced

To be absolutely certain that it doesn't interfere in any way with subtle dynamic contrasts, it would be necessary to use the data from resistance vs time measurements to construct a thermal model of each drive-unit, then write software to apply the appropriate thermal compression to a source file (or, perhaps better, undo it) for the purposes of comparison.

I agree with this 100% and I have plans to do such a test (those who follow my posts will see that this is exactly what I have been talking about). But not having done this test, Keith is simply guessing that it is not a major factor. The only data that we have in this regard is the fact that high efficiency loudspeakers are often, if not always, described as having a more dynamic sound. It is a simple fact that they have lower thermal changes and hence resistance changes. This is very strong evidence to say that the above test would show a significant effect from thermal modulation.

[CLS]

After hundreds of posts of discussions, I found that hifi guys tend to judge drivers' quality by subjective listening 'tests', so there are comments like "good hifi drivers are smoother, have more details, better for real music... etc."

While pro guys tend to find 'objective proofs of performance' to back up their theory. There're numbers, papers, measurements... etc.

It's so funny that I found, in my own 'subjective listening tests', pro drivers win, hands down. It's a more than good enough 'proof' for me. So, actually I'm one of those hifi guys, but I choose pro drivers. Really interesting here.

[kevinkr]

Originally Posted by markus76

As 45 said, dynamics is important. But how dynamic is a driver when its voicecoil starts to glow like a toaster while playing music at 70dB SPL (listening position)?

Hope this post was on topic - don't want to be locked up alone with 45 in the Sin Bin

Best, Markus

Hope that really isn't happening at 70dBSpl I suspect this becomes an issue when the required average power exceeds a few watts on a continuous basis in a voice coil that has trouble dissipating the heat. So, I suspect that in the real world that this might start to be a real issue with Spls in the high 80s with some drivers having efficiencies a number of dB lower than this. (And small voice coils made of materials that don't conduct heat well. Ever wonder why many pro woofers have aluminum VC formers?)

I have witnessed/been involved in experiments that demonstrated this effect very clearly, in practice you need to be certain that suspension limitations are not also responsible for an unexpected non-linear amplitude response to increased input power. i.e. Put in 3dB more power and see an spl increase of only 2dB vs an spl that actually decreases by a dB or more over some noted period of time. You can also measure the voltage at the driver terminals and the current flowing through the VC - thermal compression will result in both a falling spl and a falling VC current as it heats up. Rather interesting to observe.

[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

[Brett]

Originally Posted by tinitus

Makes me wonder how paper voice coils have lasted through half a century

Makes me winder how they conduct at all. Wet them down first?