4345 Project

[Ian Mackenzie]

Well I guess this is what makes the vintage stuff so much fun.

Yes the non foam surround is a plus! Either way they are both very fine drivers. (I can see myself getting a pair of 1500FE's sooner or later so I can fit a 4 way in my listening room with the rest of the mess!)

I was wondering about the voltage drive on the 2405 but it seems to work.

This afternoon I messed with a stock DBX analogue crossover adjusted to 340 hz (LR 24 db filters) and it was a breeze to set-up so I expect the Ashly should work fine.

[Ian Mackenzie]

Ian, that echoes my experience comparing the two as well. I find the 2123H to have the advantage of "higher res", while the 2122H offers a greater degree of smoothness.

Have you tried the 2123H with female vocals?

Casandra Wilson Blue Light...is my test Cd. Blown away.

While not wanting to topicalise the 2122H/2123H there are differences and there is a method in the madness to getting the best out of both drivers.

The 2122H from my recollection is a bit more lossy (as in self damping make) and obviously it does not have the bandwith of the 2123H. The trade off in smoothness comes at a price in cutting over to the horn and matching in terms of timbre. In that respect acquaplas on the diaphragm is a no brainer once you have heard the difference.

There is a certain magic to the way 2122H works in the 4345.

The 2123H on the other hand needs more passive Eq to smooth the response but its lighter cone and dust cap/surround profile breath life & resolving power above 1 khertz. This puts a different spin on the demands of the compression driver and horn down low.

When I heard the 4344mk11 in Tokyo I knew I was being spoilt.

As Chas hints if you play a lot of female vocal or jazz you are in for a treat. There is no mistaking why the Japanese hold these systems in such high esteem.

For years (back in the 80s) the 2123H was industry standard as the midrange driver of choice in large high powered studio monitors.

If you are wondering why? I just could not resist the challenge of setting up a 4344mk11 crossover with the 2123H when the opportunity came along...... What I thought would be a quick job has taken a bit longer (as these jobs do).

No doubt trad 4343 owners will read these posts and wonder what all the fuss is about.

Well the proof is in the listening.

Hence I am reluctant to spend a lot of my own time and people's money on tarding up a stock 4343 around the edges.

[Chas]

I thought you had two systems.

Yes for two channel, and re-capped (Hovland) 4430's, doing HT duty.

[Robh3606]

Hello Ian

I am glad you like the 2123's. They certainly are a fine driver. Lots of work in those crossovers, they look good.

Rob

[4313B]

Hey G - whats the likelihood of movement on those drivers? Think they'll be shipped any time soon?

The second coat needs to dry overnight. I did the first coat last Sunday night. I did the second coat this afternoon. I want to run curves on the two 2425H's mounted on 2307's and save the data for LEAP.

[4313B]

I want to run curves on the two 2425H's mounted on 2307's and save the data for LEAP.

Impedance curves include one with an 8 ohm L-Pad set at 4 ohms / 13 ohms and a 16 ohm L-Pad set at 8 ohms / 20.8 ohms, roughly 12 o'clock. Easy enough to see how opening an L-Pad wide open would have an effect on any intended voltage drive.

[Ian Mackenzie]

Thanks.

I wonder what the LR 1.0 mH + 7.5 ohms does to the impedance curve?

Ian

[4313B]

Red is just the 2425H (L-Pad wide open). Blue is the 2425H with the 1.0 mH 7.5 ohm LR conjugate. The other three plots are L-Pad settings with the 3-2 wiper set at 2 ohms, 3 ohms and 4 ohms along with the conjugate.

The second graph compares the 2425H and L-Pad set to 4 ohms without (red) and with conjugate (blue).

[Ian Mackenzie]

Excellent.

[4313B]

Both pairs of aquaplased diaphragms shipped via U.S. Postal Service today. The Post Office had to "repackage" the pair going to Australia with "registered" tape and stamps so that one would know if anyone opens the package before it gets to where it's supposed to go.

[richluvsound]

Gents,

I took the tads out and put in the LE85 from the summit. The seal is still intact - original ali dia

I guess I'm saying this for next person that decides they must have the next big up-grade. It really is a fine sound as is. No eq , passive xo . The Ali is much warmer IMHO.

just my 2 pence worth.

Good luck with the project .

Rich

[JBLCanuck]

Both pairs of aquaplased diaphragms shipped via U.S. Postal Service today. The Post Office had to "repackage" the pair going to Australia with "registered" tape and stamps so that one would know if anyone opens the package before it gets to where it's supposed to go.

Can't wait to hear the fruits of your & Ian's labour Giskard....thanks very much for your help with the project!

[4313B]

Gents,

I took the tads out and put in the LE85 from the summit. The seal is still intact - original ali dia

You might want to pull the backcaps off and make sure there isn't a whole bunch of rotted junk inside.

[Mannermusic]

You might want to pull the backcaps off and make sure there isn't a whole bunch of rotted junk inside.

Happened to see the post - yes, are those old foam dampers (or whatever they are called) for the vintage drivers still available? If not, what's the recommended replacement? My 30 yr. old 375s are as you describe above! Mike

[richluvsound]

You might want to pull the backcaps off and make sure there isn't a whole bunch of rotted junk inside.

thanks 4313b . Are these the drivers with foam (once foam) in ?
I wont bother asking you which is more important - foam or seals lol.

Rich