An E2 inspired loudspeaker: Quick but not dirty

[Ian Mackenzie]

Hi Rich,

Thanks for the insight.

Why not come out for a summer vacation, blonde's, rock concerts its all here.

Mr Widgets horns are no doubt nice but far to heavy for shipping.

Shipping those wood horns on ebay is $400. If they keep relisting them I might get excited.

The woofers are on the immediate agenda.

Following several emails from Yuichi in Japan I think it is quite doable to make a wood horn out of suitable lumber.

I am no woody but we have hardwoods available locally and some imported timber specialist

This link is one way of doing it.

http://www.geocities.jp/arai401204/H.../A290-S90.html

From viewing another local forum is would seem at least a few guys have carved these horns here and in NZ. I need to talk to them about their experiences.

Ian

[Ian Mackenzie]

There is a possibilty I might acquire some Tad 4001 drivers.

If the deal happens it will mean I have have at least a means of verifying the performance of the 290 horns by Yuichi as those particular horns were designed to match the Tad 4001.

Pending how it all comes out I may end up running two Tad 1601a woofers per box. Alternatively I may run a Tad 1603 actively as an optional modular helper woofer for movies. I am not mad keen on using large iron core chokes for creating passive filters for helper woofers. Such are the restrains of the marketing department.

There are several commercial offering including this monitor by G.A in the lower image. Its actually quite clever.

These are just ideas but by extending the concept beyond a simple two way the system has more universal performance.

[Hoerninger]

Ian, as you are thinking in public, just some added brainstorming:

... a Tad 1603 actively as an optional modular helper woofer for movies.

Formerly I was always affiliated with the concept of one speaker system for each channel - fullrange passiv, plug and play. Today I reconcile with the idea of one (to four) subs, Harman has a paper on the subject. Main speakers and sub placements demand apparently different approaches.
This can make the mains smaller, although the G.A. monitor is quite nice I admit.

I am not mad keen on using large iron core chokes for creating passive filters for helper woofers.

Running active I do not see the need for large chokes, active filter design should be straight forward (class D?).
____________
Peter

[Ian Mackenzie]

The E 2 is active and it runs chokes but as I said that was probably influenced by other than technical input.

I agree the sub low frequencies are better distributed. One company over here VAS makes an AV widescreen support that is in effect a sub with distributed output.

However what my mind was toying with is in essence an Everest type layout but running the two woofers with several possible modes of operation as in parrallel up to the first crossover point of 650 hertz side by side, or as one woofer or as one helper woofer tuned to B6 alignment.

For movies the last option would perhaps have appeal for ELF extension while for heavy rock the first option would be interesting.

In its purist form of the 2nd option running one woofer unassisted would my taste in using smaller very hi quality amps where an 8 ohm load is preferred.

Ian

[Ian Mackenzie]

Still trying to sort out sourcing and purchase of drivers..difficult.

I have however been in contact wth DDS horns and discussed the use of the JBL 2435 be driver on their horns. I am going to try one of their fibre glass 110 x 40 horns and see how it goes..

The wood horns are a work in progress and will fabricated a bit later in the year

[Ian Mackenzie]

A useful inspiration C/- Nelson Pass

Thanks to TimG for the links.

http://www.diyaudio.com/forums/showt...32#post1359032

http://www.diyaudio.com/forums/showt...36#post1359036

http://www.diyaudio.com/forums/attac...amp=1195870329

[Ian Mackenzie]

Here are images of the Emilar horn (thanks to Joe)

[Joe Alesi]

Hello Ian,

DId you score the Emilar horns?????

Best
JA

[Ian Mackenzie]

Work in progress.....

[Ian Mackenzie]

While waiting for part to arrive here are two interesting links;

http://www.studiomaudio.info/onken.html

http://www.geocities.jp/arai401204/E...E170/E170.html

There are many interesting enclosures for this style of woofer including a TQWT.

The response of the woofer as seen in the above link is remarkably smooth.

In another forum the distortion of the Tad system was measured and the woofer has very lower distortion down into the bass region.

[Ian Mackenzie]

Below are actual modelling simulations of the proposed system.

The data was collected empirically and edited into SE.

Based on hard data from the designer (courtesy of Nelson Pass c/- Passlabs CA ) the voltage drives of crossover network have been carefully tailored allowing for the 3d location of the drivers and acoustic response of the raw horn/compression driver.

http://www.diyaudio.com/forums/attac...amp=1195870046

http://www.diyaudio.com/forums/attac...amp=1195870329


The actual transition from the woofer to the horn is quite sensitive to Z axis (lateral) movements.

Despite the simplicity of the network the actual measured response is very smooth within +- 2.5 db from 60-18000 hertz and the simulations support this data.

If you follow the above links Nelson mentions the design was put together for a business partner. As the story goes the system was put together in diy fashion from available drivers found in Nelson's barn one afternoon. Using a switchable crossover tool box it was found from measured response data that a simple 2nd order high pass network would enable equalization of the Emilar EH-500 horn and the Tad -4001. The rolloff of the driver starts at about 2.5 kertz and allowing for the raw response of the horn / driver the acoustical crossover point is about 750 hertz. More complex networks were attempted to obtain an even smoother response but subjectively they were not as sucessful as the simple network shown. Fortunately the Tad drivers allow relatively straight forward crossover networks and this is perhaps a legacy of the brilliant Bart Locanthi.

http://www.aracnet.com/~bart/bnl2/aesobit.html

http://www.audioholics.com/education...-enough-part-1

[richluvsound]

Hi Ian,

I cant but admire your horn in the avatar . Could post some info on here please.

Rich

[Ian Mackenzie]

Whatever turns you on.

Someone in NZ made it. I'll see if I can get more details.

If you came out here we could go over there and have closer look.

[richluvsound]

Hey Mate,

I'm just in the process of negotiating my contract at work - Paid holidays and all that. When can you get time off ? We could build those boxes in a week !

Build a Jig for the horns and bring it with me

Rich

[Ian Mackenzie]

Difficult question to answer