4345 Project

[4313B]

With stock network and the acquaplas damping the spectral balance is un even and the 2405/077 only adds the extension.

I haven't noticed any problem other than that the stock network sounds dead to me compared to the biased equivalent. The aquaplased diaphragm performs exactly like Greg suspected it would.

I'm extremely happy with the way the 4345 and 4355 have responded to the updates. As far as I'm concerned they've actually become viable again, so much so that I've decided to bother with building my own "best of breed" pair just for pure grins.

They are rediculously large but the updates make the size more tolerable. They have a visceral impact that the stock Everest II just doesn't have. I can see why they are still so incredibly popular, especially given that they are so inexpensive to obtain.

This is quite obvious when a Be or other driver is compared to a JBL driver substituted with the acquaplas. Some people have opted for a Be driver over the acquaplas after auditions.

That would be the TAD?

[Ian Mackenzie]

I guess size does matter.

I think having to resort the Be (Tad) kills the whole point (financially) of attempting to own or build a pair of these 4 ways.

People tend to be seen as an elite-ist once they start preaching that sort of thing as an only option which is utter bullshit (when the capacity to optimise a system properly is not available or beyond their skills level)

My coments were in reference to my own iterations and auditioning Bo's 4345 (Tad), Saemans stock crossover repo 4345 system and Rich's CC diy 4345 with acquaplas. I recall Rob also commenting regards Be - acquaplas differences when I was in NY.

If you had heard nothing else (which is essentially the case for most here) you would be quite content with a stock 4343. Then try a 4345 and things are different and so on. I prefer a stock 4343 to a 4430 (when properly set-up) but thats just me.

[boputnam]

Here is a response test.

Hi, Ian...

This is all quite interesting.

Remind me of your signal path? What is the active crossover being used, and what are your amps?

Great response curves, btw...

[Ian Mackenzie]

Ah,

Bo my friend.... it certainly is an interesting topic.

The graphs were in the room. Nothing fancy just common sense.

I guess my point was/is that a flat response does not mean you will get actual detail (remember those Eq'd out horns flat to 20,000 hertz in other threads.

The 2405 in the 4344mk11 seems more active in its role and I like the end result. On the sweeps I can hear it (sweeping from top down) at 16,000 hertz.

If the curves below were normalised in the link below you would see a net increase of +5 db at 11 khertz. The 4345 filter being -3 db down from the flat voltage amplitude and the 4344mk11 filter being +2 db up from the flat voltage amplitude. That in my book be very audible and can be seen in measured response in the second link. If you look at the 4343 voltage drives its has an even higher Q and is sounds more agressive at 8000 khertz.

http://www.audioheritage.org/vbullet...55&postcount=6

http://www.audioheritage.org/vbullet...&postcount=129

Another dimension of the analysis is the power response (off axis) of the 2307/2308 which is well documented. The power response falls of progressively at higher frequencies for this assembly. The 2405/077 on the other hand has a much wider power response in the 7-12 Khertz area.

Not wanting to be a stickler for detail but I think it worthy of some discussion aside from what are the well known and respected upgrades. If I can determine something sounds different I like to intuitively investigate why.

Amps Pass labs. Loads of resolution there.

Active Crossovers Passlabs / DBX.

If I get time I will hook up an original equivalent filter on the horn and the 2405 and compare.

[JBLCanuck]

I planned on having these done months ago but I got real busy this past Summer & so speakers had to go on the back burner
I finally got them insulated & my foilcal's, velcro & grills installed, now just a few things to get mounted & sorted with the Networks & we'll be in
business
Has anyone got an email address for Ian MaKenzie? The one I have isn't working & I have a few questions for him regarding hooking up his Networks.
Has anyone got any better ideas for the Network 9v battery? I was thinking a better idea would be remove the battery from the network & relocate it to the bottom of the speaker. There's plenty-O room under there for it & it just seems like lots & lots of work having to remove drivers to check/replace a simple battery....no :dont-know
Anyway...here's a pic of them wearing their new "Wrap On" insulation...that's an ugly job once they're all assembled but that's really the only way you can do it.
Thanks for everyone's help

[timc]

Very nice craftmanship!

When are you hoping to put sound through them?


-Tim

[Chas]

They're coming along great, for sure. Good idea, re. installing the battery underneath.

[BMWCCA]

Has anyone got any better ideas for the Network 9v battery? I was thinking a better idea would be remove the battery from the network & relocate it to the bottom of the speaker. There's plenty-O room under there for it & it just seems like lots & lots of work having to remove drivers to check/replace a simple battery....no :dont-know

When I got my 4345s from NewZenith the Dave Brink-built CC networks were external to the cabinets on an MDF plate with the 9v mounted to the board using NL8s to connect them to the bi-amps. I removed the woofer and mounted the board to the inside-bottom of the box, on rubber isolation feet, ditched the NL8 connection and cable, and used a Parts Express input cup already rigged with dual input posts for Pomona plugs mounted to a recessed MDF plate Brink had used to seal the "original" style network opening, but I painted it to match the black of the cabinet backs. The input cups look pretty JBL-ish to me and came complete with gasket:



Now I simply remove the four screws and pull out the plate to reach in and change the battery. Which I've decided to do on an annual basis, coming up. When I do, maybe I'll remember to take photos.

[Ian Mackenzie]

The battery will last its shelf like so its not like it needs to be accessable really. The whole mess is made to be connected and left alone.

Your schematic in the email looked accurate.

[BMWCCA]

The battery will last its shelf like so its not like it needs to be accessable really. The whole mess is made to be connected and left alone.

I'm using Duracell Procell 9v (same thing we use in our Shure wireless mics) which generally have about a 4-year "use before" date window. I'm still going to check them at the one-year point to see how they're holding up. Because I can, and because I've made it easy to do. I change them in my smoke detectors and CO detectors annually, too.

Especially after last week: http://www.readthehook.com/blog/inde...ny-gilmore/#at

Public service announcement: Make sure your smoke detector is not an ionizer-only type. Use only the photoelectric or dual-mode types if you want to save a life.
http://www.readthehook.com/Stories/2...ON-MAIN-D.aspx
I changed all of mine last year.

[Ian Mackenzie]

Ah,

The mid, horn and slot have the wiring polarity is reversed after the L pads per the original factory 3145 crossover schematics. Therefore don't forget to reverse the woofer polarity if you plan to use LR 24 db active filters......

Oh no not that polarity thingy again...Muhhahaha!

[BMWCCA]

Ah,

The mid, horn and slot have the wiring polarity is reversed after the L pads per the original factory 3145 crossover schematics. Therefore don't forget to reverse the woofer polarity if you plan to use LR 24 db active filters......

Oh no not that polarity thingy again...Muhhahaha!

Here we go again with that great maxim concerning the English language and its usage: "The first failure in communication is assuming any is taking place."

Heck, I can't even tell to what post you were replying! Random? Private e-mail? Problem with the network? 9v battery issue?

Reminds me of the old comic book, "Tales from the Cryptic"

[Ian Mackenzie]

I was replying to Marty's numerous pms and emails (not you..my pmbox is 100%) that I have not had an opportunity to reply to individually ..this step in assembly of the networks is easy to get wrong and advice is best sort from the builder hence its worth posting.

This is a lot taking place..its just not possible to post everything here at the moment.

[dkalsi]

I planned on having these done months ago but I got real busy this past Summer & so speakers had to go on the back burner
I finally got them insulated & my foilcal's, velcro & grills installed, now just a few things to get mounted & sorted with the Networks & we'll be in
business
Has anyone got an email a

Any update on your project?

[Ian Mackenzie]

Ditto,

I would also like to know how it turned out given the time and expense in preparing those networks.

Ian