Building Your First DIY Speaker - The MB27

[fuzz092888]

Photobucket works pretty well, there's also imgur and a bunch of others. Personally I use Photobucket.

 

[Adam]

Hi, Swerd. I use Photobucket and have been happy with it.

 

[Alex2507]

If you recall, I also made a pdf file of the build text with photos, just before posting it here. Do you still have it? If you need it, I can email it.

It's an excellent build thread and worth it to me to have you spend your time ...

... I can't type that with a straight face.

If you can get the pic's put back in this thread that would be cool.

The meet's this Saturday ... no rush though.

 

[Swerd]

… and worth it to me to have you spend your time ...

... I can't type that with a straight face.

OK, what's it worth to you ? (typed with a perfectly straight face )

 

[Alex2507]

OK, what's it worth to you ? (typed with a perfectly straight face )

Another $500?

 

[Alex2507]

I took these MB27s down to a DIY GTG. During play I heard a 'smooth' comment from the back of the room and Peter Bassel from the CT Audio Society showed interest in their pedigree. A few people asked about the Seas 27TFFC tweet. It seemed like I had to look at my cheat sheet like 3 different times to make sure I got it right.

There wasn't a lot of time spent on any particular speaker due to the number of speakers there. It was about 10 minutes each and excerpts from 3 songs got played. The fast pace prevented me from fiddling with toe and trying to create a sweet spot which is where these really shine. At home I have these angled down on wall mounts and toed in to where I'm sitting completely on axis. Slipping into that sweet spot from standing changes everything. That feature wasn't within my abilities to reproduce in that room seating 20 people at any given time.

I'm almost tempted to bang out my own DM designed speaker but with a bigger budget. Oh no ... I just had an idea for a cabinet, Swerd, do you still have that spread sheet for the various Murphy Blaster designs?

 

[fuzz092888]

I'm almost tempted to bang out my own DM designed speaker but with a bigger budget. Oh no ... I just had an idea for a cabinet, Swerd, do you still have that spread sheet for the various Murphy Blaster designs?

Whatcha gonna do? MBOW? CAOW? MBOW 3-way? Maybe a Phil Slim DIY build?

 

[Alex2507]

Whatcha gonna do? MBOW? CAOW? MBOW 3-way? Maybe a Phil Slim DIY build?

Towers are out of the question. I've got these lumber core, Mahogany veneer curved drawer faces that I would love to incorporate into a bookshelf speaker. The CA15 and OWI drivers are a little pricey, unless your made of money like Swerd is. In a nearfield on axis application I suspect the diminishing return thing might be in full effect with those drivers.

Now that I'm becoming aware of different drivers and prices I need to take a closer look at what's used in the ER18s. I placed a call to Sean in regards to the ribbon and dome tweeter versions. I know there are a lot of similarities in the sound but I'm more interested in the differences.

This is crazy but I just looked for placement options in our bedroom for a couple of wall mounted bookshelves. Well, it might not be so crazy if someone other than me built them ...

 

[Swerd]

I took these MB27s down to a DIY GTG. During play I heard a 'smooth' comment from the back of the room and Peter Bassel from the CT Audio Society showed interest in their pedigree. A few people asked about the Seas 27TFFC tweet. It seemed like I had to look at my cheat sheet like 3 different times to make sure I got it right.

Thanks for taking them.

Oh no ... I just had an idea for a cabinet, Swerd, do you still have that spread sheet for the various Murphy Blaster designs?

Estimated prices (as of fall 2012) are shown for pairs (shipping is not included). I might be a bit off for the x-over prices:

	Woofers
	6½"	5¼"	Dome Tweeters
Model	Seas W18	Seas CA15RLY	GR Research M-130	Hiquphon OWI	Morel MDT-20	Seas 27TFFC	x-over & various parts	Cabinets	Total
CAOW1	–	$106	–	$219	–	–	$72	$130	$527
MBOW1	–	–	$48	$219	–	–	$72	$130	$469
MB20	–	–	$48	–	$66	–	$70	$130	$314
MB27	–	–	$48	–	–	$62	$70	$130	$310
Ellis 1801b	Kit from Ellis Audio includes W18 woofer, OW1 tweeters, premium crossover parts, all other required parts & detailed instructions for $750	$100	$850

<tbody>
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I know Dennis has a crossover design for a CAOW1 where the CA15 mid woof is replaced by an ER15.

I think he also has general plans for a larger 2-way ER18 and Fountek ribbon tweeter.

Ignore the row for the MB20 design, that tweeter is no longer made.

You should persuade ImcLoud that he needs 20 pairs of custom made speakers, so he can throw out that garbage he now has .

 

[Alex2507]

I just looked and the M-130s are $54. Seas 27 TFFC are $92 for pairs. I think you got the cabinet price wrong. Now they are $108 each. At the meet I said to Peter Bassel that the electronics was around $250 and the cabinets were around $250. Close enough. That 1801b requires a cabinet about twice the size (0.77 ft^3) so I can forget about that.

They have that NY DIY Competition. They have more room and do the curtain and blindfold thing. I'm tempted to see if anybody wants me to bring hand cuffs. Seriously, it would be fun to bring a solid performer to that. I'm also intrigued with the passive reflex idea. I don't know much about it but dlr (the usual host for the New England DIY) had some thoughts he shared on that.

 

[Adam]

They have more room and do the curtain and blindfold thing. I'm tempted to see if anybody wants me to bring hand cuffs. Seriously...

I really doubt anyone here thought that you were joking.

 

[Swerd]

I just looked and the M-130s are $54. Seas 27 TFFC are $92 for pairs. I think you got the cabinet price wrong. Now they are $108 each. At the meet I said to Peter Bassel that the electronics was around $250 and the cabinets were around $250. Close enough. That 1801b requires a cabinet about twice the size (0.77 ft^3) so I can forget about that.

The prices keep going up… and up. The prices in that table were when you were still thinking you wanted to build something that was a step up from the BR-1s. I can't remember just when we talked about that, but I made that table so you could quickly compare some 2-way designs. I did look up the prices of the various drivers, but I guestimated the prices of the crossover parts and the cabinets. Clearly, some prices have changed since then. Copper coils and woodwork have gone up a lot. If you're at all serious, I can look up present day prices.

You seem to have had a good time yesterday.

I'm also intrigued with the passive reflex idea. I don't know much about it but dlr (the usual host for the New England DIY) had some thoughts he shared on that.

What is a "passive reflex"?

I could make some guesses, but they wouldn't have anything to do with speakers .

 

[sawzalot]

Prices getting so high that the DIYers will have to buy em already put together.

 

[Adam]

Prices getting so high that the DIYers will have to buy em already put together.

How about that? I actually am a DIYer...I'm just way ahead of my time.

 

[Swerd]

Prices getting so high that the DIYers will have to buy em already put together.

Remember, those price estimates include the cost of pre-made and pre-finished cabinets. They are well made, but add a lot to the cost.

If you build your own cabinets, MDF is cheap, veneer runs widely from inexpensive to extremely expensive, and labor charges are zero.

 

[Alex2507]

What is a "passive reflex"?

I could make some guesses, but they wouldn't have anything to do with speakers .

LOL! I bet you could. Passive radiator. I asked the same thing.

Reducing the port volume from Vb is my main interest. A secondary interest is what dlr had to say about his preference for the sound of PRs.

You don't need to go looking up part costs. I'm slowly coming to my senses. Here's the breakdown. Two bedroom condo. 9 speakers. 2 active subs. 2 passive subs. 2 rec'rs. 5 external amps. In another day or two I'll be back to normal and not thinking about building something else 40 miles away from home.

I had a blast yesterday. The pic's are up on PETT. Some of these guys produce some really good sounding original designs. I was very happy going home with the MB27s. The size, look and cost are a perfect fit for my particular needs. In my application the sweet spot is like stepping into another 3 or 4 hundred dollars worth of speakers. It blows me away ... every time.

 

[Swerd]

LOL! I bet you could. Passive radiator. I asked the same thing.

Reducing the port volume from Vb is my main interest. A secondary interest is what dlr had to say about his preference for the sound of PRs.

I've never seriously thought about building a PR bass cabinet. After what I've heard with Paul Kittinger's MLTL design (a hybrid of a ported reflex and a classic TL) I've thought that was the best way to go. Of course, the devil is in the details.

I had a blast yesterday. The pic's are up on PETT. Some of these guys produce some really good sounding original designs. I was very happy going home with the MB27s. The size, look and cost are a perfect fit for my particular needs. In my application the sweet spot is like stepping into another 3 or 4 hundred dollars worth of speakers. It blows me away ... every time.

I'm really glad you had a good time. Think how crumby you'd have felt if you had gone but didn't bring the MB27s.

I'll go look at the photos right now.

http://techtalk.parts-express.com/showthread.php?240923-DIY-New-England-Feb-22-2014/page4

I have to roast coffee (takes about an hour for 3 runs) but I can spend a few minutes looking at your photos first .

 

[Alex2507]

Think how crumby you'd have felt if you had gone but didn't bring the MB27s.

Now that I think about it, one person who stayed on point was Pete Basal of the CT Audio Society. He didn't change seats and paid attention the whole time. He seemed to know about MurphyBaster Productions. Anyway he said, "The builder wanted them here?" after I informed everybody that "the MB27s are a Dennis Murphy design built by (your name) and he (you) wanted them here, so they're here ... and here they are".

I was good just bringing cherry pie.

The group had spectators, builders and designers. Owning a built design puts me squarely in the category of the guy in the know about pie. But I have something special for you in a PM ... not like the special thing you sent me in a PM. I meant to say that that was disgusting. What is wrong with you?

 

[Adam]

... not like the special thing you sent me in a PM. I meant to say that that was disgusting. What is wrong with you?

I don't think anyone can top a PM from the Deuce. Literally. Those ladies are just too large...

There's no smiley...just shivering from the memories...

 

[Alex2507]

I don't think anyone can top a PM from the Deuce. Literally. Those ladies are just too large...

There's no smiley...just shivering from the memories...

I'm afraid this was made worse by the fact that I know how to establish boundaries and he completely caught me off guard by a total indifference to something that has worked for me for my whole life. We were talking about some Salk SongCenter wall mounting that is beyond slick and he tricked me by including this completely inappropriate link to a pic that made me scream and jump a little. You wanna see?