JBL Performance Series

[MJC]

So I'm cruising the Revel listings and see this:

http://cgi.ebay.com/Revel-B12-Subwoo...QQcmdZViewItem

I'm thinking, darn that cone looks familiar. It turns out that it's a 10" Aluminum cone with an SFG magnet powered by a 650W amp.
the family resemblance is uncanny.

First, his Revel B12, then one of my HTPS400 drivers.

I'm surprised that Revel decided to build a sub that small. When they closed out the Sub15, which was the JBL SUB1500 driver, they went to the Sub30, which was a dual 15" active/passive design.

[MJC]

While I was listening to Fleetwood Mac's Rumours, DVD-A style, on the PT800 system the thought came to me. What if an ultra tweeter was added to the top of the baffle just above the EOS waveguide, as is in the Studio L series?
When I had the L890s and listened to them on a daily basics, I remember getting a sensation, mentality, that I've never experienced with other speakers. Unfortunately, I've yet to hear the K2 or DD66000.
The subject as been discussed before, that even though we don't hear above 20khtz the brain reacts to frequencies above that.

But what tweeter to add? That is the main question. And of coarse, what additional parts to add to the xo? Would that make a great speaker better or what?

[Robh3606]

Can you get a part number from JBL on the supertweeter in the 890?? That might be your easiest way to add one.

Rob

[MJC]

Actually the JBL support shows that its not available.
In fact most of the parts for the L890 are not available.
And I doubt the one in the ES series is the same, completely different waveguide.
It must make a difference or they would use the same ultra in all series that have an ultra.

[mikebake]

The subject as been discussed before, that even though we don't hear above 20khtz the brain reacts to frequencies above that.

If you can't hear it, how can "the brain" react?

[ColdFyre22]

If you can't hear it, how can "the brain" react?

You can't hear it but i believe it has been proven that the inner ear can "feel" those >20khz frequencies.

[pos]

With 44.1khz sampling of nowadays CD you could not hear it anyway, they are filtred by the ADC.
22.05khz is the maximal theoritical frequency you can reproduce with a 44.1khz sampling rate:
http://en.wikipedia.org/wiki/Nyquist...mpling_theorem

[Titanium Dome]

We've touched on this before with regard to whether or not these UHFs are important. In addition to our various opinions, there is science on the subject, and it's convincing to me.

I believe that the impact of UHF is significant enough that the lack of an UHF driver is the single greatest deficit of the Performance Series. The Performance Series is an "old" design surrounded by newer designs. The Project Array Series, K2 Series, and Everest II Series all have UHF drvers, as do the Studio L Series and the upcoming ES Series.

Marketing smoke-and-mirrors or engineering triumph? Well, believe whatever the heck you want, but if you want a bit of science, try these.

http://www.cco.caltech.edu/~boyk/spectra/spectra.htm

http://jn.physiology.org/cgi/content/full/83/6/3548

http://www.nhk.or.jp/strl/publica/labnote/lab486.html

There's more where those came from.

If I could, I'd add UHF drivers in (EOS Waveguides) to the PT800s in the front stacks at a minimum.

[MJC]

If I could, I'd add UHF drivers in (EOS Waveguides) to the PT800s in the front stacks at a minimum.

That was my exact thought process. And if needed to gain enough space above the original EOS, I'd build a bubble out of Ash, that was hogged out for the ultra tweeter to set in. As has been done in various speakers of other brands.
But as I found out yesterday, the ultra for the Studio L series is not currently available. So at this time, that only leaves the beryllium compression driver of the K2 or DD66000 and those ain't cheap.
The only other series with ultras is the ES and they're still not available.

Inaudible High-Frequency Sounds Affect Brain Activity: Hypersonic Effect

With about 7 months of listening to the L890s I believe that whole heartedly.

[Titanium Dome]

Well, I have one 045Be. I suppose I could get another, but I doubt its efficacy in an EOS Waveguide. :dont-know

[Titanium Dome]

You could try to score a pair of L810 bookshelf speakers and harvest the UHF drivers. You might even benefit from some of the crossover components.

[MJC]

You could try to score a pair of L810 bookshelf speakers and harvest the UHF drivers. You might even benefit from some of the crossover components.

And use the Bi-Radial® horn, as the EOS waveguides don't seem to be available either. And it looks like there is enough space between the EOS and the top of the baffle for the horn.
Right now, there are more parts available for the PT800 than the Studio L.
The only part not available for the PT800 is the tweeter w/EOS.

[ColdFyre22]

You could try to score a pair of L810 bookshelf speakers and harvest the UHF drivers. You might even benefit from some of the crossover components.

E-Warehouse has a pair of L810's at $259.90

http://cgi.ebay.com/New-JBL-Studio-L...QQcmdZViewItem

[MJC]

If I was to buy a pair of Studio L speakers, for harvest purposes, I'd harvest more than just the ultra tweeters. I'd pull the EOS waveguides and mount them to the faces of the 066 tweeters on my CC L212s to see(hear) if they made a difference.
Ya, I saw those 810s.

[aht3]

Nothing like a Frankenspeaker