B&W speaker project from parts

[BilboBaggins]

I had a good day at the thrifts today, and even got my French Tutor a Citation 605 acoustic guitar!

It was when I got home that things got interesting. I’m looking into Facebook to mark one of my items as sold, and I see an ad for speaker parts for free. The location is in the country about 35 minutes from home, so I ask my wife if she wants to come with me, and we can grab a bite to eat on the way home. Sure!

So I drive out to Dunrobin, and pick up 4 x B&W BN-2001 mid/woofers, 2 MG DMT-100, and a pair of B&W DM-580 crossovers.

I suspect the cabinets were roached and the guy saved the drivers. In researching these, it seems the DM-580 has dual woofer BN2001, and the DM-560 uses a single bn2001 in the bookshelf cabinet.

So here is what I’m thinking of doing, just for fun. I have a pair of EPI M110 cabinets with no drivers, and I have a pair of Ohm E cabinets with just a single woofer and tweeter. Since these are all 8 inch woofer cabinets, I thought I would try a pair of the B&W woofers in them, and use the DMT-100 tweeters with them. Then I might try them in the Ohm cabinets. The Ohm cabinets are nice walnut veneer cabs in pretty good condition, and the EPIs have vinyl veneer.

Who knows, I might end up with some nice sounding speakers and put a pair of these cabinets to good use!

Hers a picture of one pair of the woofers.

 

[BilboBaggins]

It was easier to get to the Ohm cabinets. Here are my two options.



I realize the B&W DM-560 and 580 are ported Speakers. I’m thinking I’ll try them like this first with the 580 crossover, and if I like them like that, leave them. If I don’t like them, I’ll move over to the EPI cabinets, try them like that, and then try them ported. That should give me an idea if I want to port the Ohm cabinets.

Does anyone have a picture of the dm-560 crossovers? I’ll probably find one on eBay...

I want to compare them and see if it is a drastic job to modify the 580s.

 

[BilboBaggins]

Tonight, I spent some time deciding on an approach. Just for fun and giggles, I used the white and blue wire from the LF part of the crossover for the woofer and I did a direct connect of the MG tweeter to the HF out of the crossover, laid the speaker flat, raised the woofer cavity of the cabinet so it was flush and sealed, and tested it out. It is definitely better than Philips Spectron cabinet that was connected to the other channel.

I think this is going to work, with a little tweaking.

The MG tweeter is a direct pop in and looks great! Unfortunately, the B&W woofer is slightly too large to fit in the cavity. This was why I raised the woofer cavity. This was purely experimental. I think I’m going to start researching the parameters to use for a crossover. I won’t be able to use the B&W crossover. I’m thinking I would either have to modify it to be equivalent to the DM-560, in which case the crossover is still wrong because I’m not using a B&W tweeter, and I don’t want to port the speaker cabinet, or make one from scratch. I could do a point to point crossover build. Just need to figure out the best crossover to build.

 

[BilboBaggins]

Now, the problem I’m facing is I don’t know what the Fs value is on either the woofer or the tweeter, so I’m missing an important parameter to use the crossover calculator.

Aside from that, I want to build a second order point to point crossover. I may have to dig out my old college testing board, and build the crossover on that outside of the cabinet. Then I can easily change components and hear the difference right away.

Now where did I put that thing?

 

[BilboBaggins]

So I found my prototype board (had to remember that name as it has been so long since I last used one), and while I was looking for it, I found a set of Advent/1 crossovers I have. Then I had a duh moment and decided to use the Ohm L crossover. Why didn’t I think of that before!

Got the two speakers all wired up and sealed. They sound good, but I find the highs are too bright, and the bass is muffled. That makes sense considering the woofers are for ported speakers, and these are sealed cabinets. Also, I realized the tweeters may need breaking in, so I have been playing them a lot this week to hopefully do that. They are sounding better, and I’ve oiled the walnut veneer and they are starting to look good.

This was just to try them out. I may put a port in each of the vinyl veneer covered EPI cabinets I have and see how they sound in there. I just remembered I have some Paisly speakers in which the cabinets are trashed. Too bad because they were nice speaker boxes. Maybe I’ll try those drivers in the Ohm cabinets.

 

[Ramseybella]

Seems you're talking to yourself...
Get yourself a meter so you can check Ohms.
Nice looking speakers by the way.

 

[BilboBaggins]

Yeah, that happens here sometimes.

The Ohms are now FrankenOhms. But I’ve more experimenting to do. I want to try some different drivers in these cabinets. I’ve also got some drivers in the roached Paisley cabinets that are designed for a non ported cabinet. Should be a better fit.

I do have a meter and everything driver wise measures as it should. There’s nothing wrong electrically except I’m using crossovers designed for different drivers.

 

[Bynem]

Good luck with the experimentation. I am not adventurous enough for this kind of work.
All I've done with my B&W speakers (three pair) is recap one set.

 

[BilboBaggins]

Good luck with the experimentation. I am not adventurous enough for this kind of work.
All I've done with my B&W speakers (three pair) is recap one set.

Thanks! I wasn’t either when I first got back into Audio, but over the years, I’ve accumulated all kinds of spares. I also lucked out getting four free B&W woofers, which makes it easier to play around. I’m not affecting any of my treasures.