diyAudio

diyAudio (http://www.diyaudio.com/forums/)
-   Planars & Exotics (http://www.diyaudio.com/forums/planars-exotics/)
-   -   Anyone swap 12" for dual 8" woofers on ESS AMT Heil speaker? (http://www.diyaudio.com/forums/planars-exotics/207865-anyone-swap-12-dual-8-woofers-ess-amt-heil-speaker.html)

decooney 1st March 2012 02:17 AM

Anyone swap 12" for dual 8" woofers on ESS AMT Heil speaker?
 
Has anyone here every tried swapping out a single 12" woofer for dual 8" woofers on an ESS AMT Heils speaker before?

If so, it would be great to hear from anyone here, what woofers you ended up with, and any sort of work you had to do to the crossover make it sound right. I am hoping to try running two 8s in place of the original single 12.

Background:
I've always wanted to try this with two smaller/faster woofers in a Di'Apolito arrangement with a better chance of keeping up with the Great Heil tweeter. I have seen the ess450 that runs dual 7" Seas woofers, but that's way too rich for me. I just want to see if it can be done by using some affordable mid-woofers, re-using the factory crossover and great Heil, using four new (efficient 7" or 8" eight ohm) woofers, including am all new cabinet design and resize according to the new woofers I will select.

planet10 1st March 2012 03:32 AM

In one of the AMT rebuilds we did (the cabinets are not very good) we used 2 9" Fostex (no longer available) in a bipole arrangement. Turned out very good.

http://p10hifi.net/tlinespeakers/FAL...eil-fostex.jpg

dave

decooney 1st March 2012 03:45 AM

Hey Dave,
I did see these before, however I did not realize until now that I missed something. To reconfirm, are you stating there is a 9" Fostex woofer on the front, and another woofer on the rear for each of these speakers? If two each per speaker, are the woofers in our out of phase to each other? As you can imagine, I'm very interested in one part for sure - what did you do for the crossovers? I see something on your site about a "simple first order x-over". I have a set of original (NOS) AMT Monitor crossovers I want to play with but need a good pair of crossover once I pick the woofers. I'm thinking of running two 7s or two 8s, but not sure yet. If you build the crossovers and have recommendations, it would sure take away guesswork on my part. Also, I may run these on top of my two 12" powered subs as another option, so I'm looking for these to image well, and crossing them over somewhere between 1500-2000hz.

planet10 1st March 2012 03:56 AM

1 Fostex on the front and one on the back (not really woofers, they reach up to 10k -- makes the XO easy), in phase (bipoles). We did active (PLLXO) and passive -- ended up passive at 2k 1st order.

dave

decooney 6th March 2012 02:43 AM

...still hoping to find someone who has tried it with dual 7" or dual 8" woofers?

JohnL 4th April 2012 11:30 PM

Dual 8's here. I used Dayton RS225s with a high slope crossover. I've been meaning to do something more creative for a while, but I've had these things set up for 8-9 years it seems. They sound pretty good.

John L

decooney 5th April 2012 02:05 AM

Quote:

Originally Posted by JohnL (Post 2973127)
Dual 8's here. I used Dayton RS225s with a high slope crossover. I've been meaning to do something more creative for a while, but I've had these things set up for 8-9 years it seems. They sound pretty good.

John L

John,
Can you share any photos of what you put together?

It would be fun to see what you did. I'm down to the wire probably going to go with an MTM configuration vs. TMM. In doing so, I lose some volume which requires a bigger cabinet that I was trying to avoid.

JohnL 6th April 2012 12:08 AM

I posted the schematic here a few years ago

Here's the Link

Or did you mean a picture of the loudspeaker itself? It's not much to look at, birch ply boxes with a double thick front baffle, AMT sitting on the top. I put oak laminate on the front, but stopped there because I was going to start another project. I think that was in 2006. :) The "next project" actually did get started about 6 months ago, it's still raw MDF with drivers waiting for a crossover design. I don't work fast.

John L


All times are GMT. The time now is 12:25 PM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright 1999-2014 diyAudio


Content Relevant URLs by vBSEO 3.3.2