MCM Aluminum cone drivers for TL ?

[nepaeric]

Happy Thanksgiving everyone. Just thought I'd mention a driver my brother bought 20 of and got an insane cheap, unit cost of $13.00 each, so I agreed to buy 3. (2 for a main pair, and 1 for a center channel) These MCM 6-1/2" woofers are aluminum cone, rubber surround units that are fully shielded, which makes them ideal for A/V use. (They are very similiar to the Dayton aluminum cone 7" ones sold by PE)
They are rated for 75 watts RMS/150W peak. Here are the specs: Sens- 88dB, Impedance- Re: 5.9 ohm, Le- 2.15mH, Freq- 45-12,000 Hz, Fs- 47 Hz, Qts- 0.35, Qes- 0.39, Qms- 3.49, Vas- 12.89 L, Xmax- 3.4 mm

I am currently discussing with one of you the possibilities of modeling a TL design around this woofer and considering using an AWO10E1 Audax shielded polymer dome tweeter I can get from my brother, who has several of these popular units, and willing to give me 3 of them. I'd like to look at a simple, decent 2 way crossover with a frequency that would work well with it, and build three timbre voice matched speakers for HT use.

I'm really interested in hearing some of your opinions and ideas out there, and whether you think these components offer a viable project that would yield a good end result. I would like to build something in the form of a narrow, tall, column style tower for aesthetic appeal and contemporary appearance for the main pair and anything that'd work for the center. I plant to "glass-over" the cabinets. (Using ordinary Dyna-Glass auto body fiberglass) I will likely construct of 3/4 MDF, and form and shape to give the appearance of the Zalytron cabinet called "Rosinante." Interested in hearing any opinions.

[johnastockman]

> Happy Thanksgiving everyone. Just thought
> I'd mention a driver my brother bought 20 of
> and got an insane cheap, unit cost of $13.00
> each, so I agreed to buy 3. (2 for a main
> pair, and 1 for a center channel) These MCM
> 6-1/2" woofers are aluminum cone,
> rubber surround units that are fully
> shielded, which makes them ideal for A/V
> use. (They are very similiar to the Dayton
> aluminum cone 7" ones sold by PE)
> They are rated for 75 watts RMS/150W peak.
> Here are the specs: Sens- 88dB, Impedance-
> Re: 5.9 ohm, Le- 2.15mH, Freq- 45-12,000 Hz,
> Fs- 47 Hz, Qts- 0.35, Qes- 0.39, Qms- 3.49,
> Vas- 12.89 L, Xmax- 3.4 mm

> I am currently discussing with one of you
> the possibilities of modeling a TL design
> around this woofer and considering using an
> AWO10E1 Audax shielded polymer dome tweeter
> I can get from my brother, who has several
> of these popular units, and willing to give
> me 3 of them. I'd like to look at a simple,
> decent 2 way crossover with a frequency that
> would work well with it, and build three
> timbre voice matched speakers for HT use.

> I'm really interested in hearing some of
> your opinions and ideas out there, and
> whether you think these components offer a
> viable project that would yield a good end
> result. I would like to build something in
> the form of a narrow, tall, column style
> tower for aesthetic appeal and contemporary
> appearance for the main pair and anything
> that'd work for the center. I plant to
> "glass-over" the cabinets. (Using
> ordinary Dyna-Glass auto body fiberglass) I
> will likely construct of 3/4 MDF, and form
> and shape to give the appearance of the
> Zalytron cabinet called
> "Rosinante." Interested in hearing
> any opinions.

Are these the MCM woofers? I know they had some different varieties of the aluminum cones. If they're the ones with a dust-cap, I used them in a center channel for a friend with a XO that wasn't optimized, but tweaked over about 2 weeks of listening. That was before I found PE and Jeff's PCD. He loves it, though, so I guess that's what is important! It replaced an expensive Infinity center.

John A.

[nepaeric]

Hi, John. Appreciate your response. Yes, these are the aluminum cone, High-Excursion versions with black center dust caps, and are MCM Electronics "Audio Select," part # 55-1862.
My brother is involved with autosound, and ordered about 20 some for stock and to try them for his own use. I believe he has designs on using them in D'Appolito configuration and building a voice matched, 4 ohm, threesome for his own, personal HT.

I am trying to figure on a good TL Design using these interesting woofers if it will model well and work. They really intrigued me when he got them, so I bought a few from him. I figured if they worked out well he still has them and I could get more, or even order them. They are certainly dirt-cheap enough, and would be a great project if they wound up being part of an inexpensive build project that sounded good. They really are attractive, to boot. I'm looking to build a pair of Transmission Lines and matching center channel if this is something that could be modeled with any promise. Is this driver a good, promising candidate for something like this ? (see link below) Just wondering, because I like this modern, contemporary styling, and could possibly build up the top with the rounded contour to somewhat match the "Rosinante" and possibly fabricate a seperate compartment for the tweeter on the top. Thanks. I truly appreciate your help and technical guidance.
<A HREF="http://www.members.tripod.com/oakleyspeakers/MAIN.html">http://www.members.tripod.com/oakleyspeakers/MAIN.html</A>

> Are these the MCM woofers? I know they had
> some different varieties of the aluminum
> cones. If they're the ones with a dust-cap,
> I used them in a center channel for a friend
> with a XO that wasn't optimized, but tweaked
> over about 2 weeks of listening. That was
> before I found PE and Jeff's PCD. He loves
> it, though, so I guess that's what is
> important! It replaced an expensive Infinity
> center.

> John A.

[nepaeric]

<A HREF="http://www.mcminone.com/product.asp?...me=MCMProducts">http://www.mcminone.com/product.asp?...me=MCMProducts</A>

> Hi, John. Appreciate your response. Yes,
> these are the aluminum cone, High-Excursion
> versions with black center dust caps, and
> are MCM Electronics "Audio
> Select," part # 55-1862.
> My brother is involved with autosound, and
> ordered about 20 some for stock and to try
> them for his own use. I believe he has
> designs on using them in D'Appolito
> configuration and building a voice matched,
> 4 ohm, threesome for his own, personal HT.

> I am trying to figure on a good TL Design
> using these interesting woofers if it will
> model well and work. They really intrigued
> me when he got them, so I bought a few from
> him. I figured if they worked out well he
> still has them and I could get more, or even
> order them. They are certainly dirt-cheap
> enough, and would be a great project if they
> wound up being part of an inexpensive build
> project that sounded good. They really are
> attractive, to boot. I'm looking to build a
> pair of Transmission Lines and matching
> center channel if this is something that
> could be modeled with any promise. Is this
> driver a good, promising candidate for
> something like this ? (see link below) Just
> wondering, because I like this modern,
> contemporary styling, and could possibly
> build up the top with the rounded contour to
> somewhat match the "Rosinante" and
> possibly fabricate a seperate compartment
> for the tweeter on the top. Thanks. I truly
> appreciate your help and technical guidance.
>
> <A HREF="http://www.members.tripod.com/oakleyspeakers/MAIN.html">http://www.members.tripod.com/oakleyspeakers/MAIN.html</A>

[nepaeric]

Oh, well. I guess the link is not working. If you go directly to MCM Electronics website, you can find this woofer by entering the part # in the "Product Search" column. Part # 55-1862

Thank You to anyone who might be able to help out.
Happy Thanksgiving and Warm Regards, Eric

[terryo]

> Hi, John. Appreciate your response. Yes,
> these are the aluminum cone, High-Excursion
> versions with black center dust caps, and
> are MCM Electronics "Audio
> Select," part # 55-1862.
> My brother is involved with autosound, and
> ordered about 20 some for stock and to try
> them for his own use. I believe he has
> designs on using them in D'Appolito
> configuration and building a voice matched,
> 4 ohm, threesome for his own, personal HT.

> I am trying to figure on a good TL Design
> using these interesting woofers if it will
> model well and work. They really intrigued
> me when he got them, so I bought a few from
> him. I figured if they worked out well he
> still has them and I could get more, or even
> order them. They are certainly dirt-cheap
> enough, and would be a great project if they
> wound up being part of an inexpensive build
> project that sounded good. They really are
> attractive, to boot. I'm looking to build a
> pair of Transmission Lines and matching
> center channel if this is something that
> could be modeled with any promise. Is this
> driver a good, promising candidate for
> something like this ? (see link below) Just
> wondering, because I like this modern,
> contemporary styling, and could possibly
> build up the top with the rounded contour to
> somewhat match the "Rosinante" and
> possibly fabricate a seperate compartment
> for the tweeter on the top. Thanks. I truly
> appreciate your help and technical guidance.
>
> <A HREF="http://www.members.tripod.com/oakleyspeakers/MAIN.html">http://www.members.tripod.com/oakleyspeakers/MAIN.html</A>

Eric,
The older #1860 MCM 6.5 inch woofer has been used in many designs over the years. Not bad for the money, and can be used to create a pretty nice speaker. How close the #1862 specs are to the #1860's I'm not sure, but I'd bet that they're somewhat similar. The link you give (oaklyspeakers) seems to be a very dated design, that is, before Augsberger and King's work. I know that it was suggested to you 4 or 5 days ago to use this software to correctly model the TL cabinet, have you done so yet?

Best Regards,
TerryO

[nepaeric]

> Eric,
> The older #1860 MCM 6.5 inch woofer has been
> used in many designs over the years. Not bad
> for the money, and can be used to create a
> pretty nice speaker. How close the #1862
> specs are to the #1860's I'm not sure, but
> I'd bet that they're somewhat similar. The
> link you give (oaklyspeakers) seems to be a
> very dated design, that is, before
> Augsberger and King's work. I know that it
> was suggested to you 4 or 5 days ago to use
> this software to correctly model the TL
> cabinet, have you done so yet?

> Best Regards,
> TerryO

Hi, Terry. I did go to quarter-wave.com ,as as result of a search on "Martin J King." I tried to download MathCad, to no avail. Being honest, I am much more confident in my building capabilities than I am in design. I have also been looking on t-linespeakers.org , and looking at the projects of which King has his own in. I don't know where to begin using the latest technology in TL design. Any suggestions ? Thanks, Eric

[nepaeric]

MathCad was the worksheets I had trouble finding. I heard alot of talk about them, and modeling a driver using them. WinISD program I heard discussed in this forum is the program I meant, that I was trying to download.

In any case, I need help, and am a bit intimidated and overwhelmed by much of this about TL design. I can build most anything as can be built with my woodworking skills and a vast array of wookworking tools and equipment. I even have a good supply of 3/4" MDF, plywood, veneers and formica, as well as a brother who can help with a pretty good supply of speaker goodies to help fill most any needs. Thanks, Eric

[terryo]

[nepaeric]

I appreciate the referral. I will check it out over the weekend, and let you know in this forum if I come up with anything. Thank You, Eric

[Paul K.]

I modeled this MCM driver in a short and fat ML-TL, a long and thin ML-TL and a tapered TL, using Martin King's MathCad software and none of them gave even reasonably good results AFAIC. However the Dayton DA175-8 gave good to very good results for all three varieties of TLs. I really liked the results for a 62-inch long, 13:1 tapered TL in a cabinet volume of right at 1.5 cubic feet; F3 was ~33 Hz. Both ML-TL versions gave comparable results, even better in some other areas. I would not recommend the MCM driver for a TL, and the extra 7 bucks the DA175 would cost you is well worth it.
Paul

> Happy Thanksgiving everyone. Just thought
> I'd mention a driver my brother bought 20 of
> and got an insane cheap, unit cost of $13.00
> each, so I agreed to buy 3. (2 for a main
> pair, and 1 for a center channel) These MCM
> 6-1/2" woofers are aluminum cone,
> rubber surround units that are fully
> shielded, which makes them ideal for A/V
> use. (They are very similiar to the Dayton
> aluminum cone 7" ones sold by PE)
> They are rated for 75 watts RMS/150W peak.
> Here are the specs: Sens- 88dB, Impedance-
> Re: 5.9 ohm, Le- 2.15mH, Freq- 45-12,000 Hz,
> Fs- 47 Hz, Qts- 0.35, Qes- 0.39, Qms- 3.49,
> Vas- 12.89 L, Xmax- 3.4 mm

> I am currently discussing with one of you
> the possibilities of modeling a TL design
> around this woofer and considering using an
> AWO10E1 Audax shielded polymer dome tweeter
> I can get from my brother, who has several
> of these popular units, and willing to give
> me 3 of them. I'd like to look at a simple,
> decent 2 way crossover with a frequency that
> would work well with it, and build three
> timbre voice matched speakers for HT use.

> I'm really interested in hearing some of
> your opinions and ideas out there, and
> whether you think these components offer a
> viable project that would yield a good end
> result. I would like to build something in
> the form of a narrow, tall, column style
> tower for aesthetic appeal and contemporary
> appearance for the main pair and anything
> that'd work for the center. I plant to
> "glass-over" the cabinets. (Using
> ordinary Dyna-Glass auto body fiberglass) I
> will likely construct of 3/4 MDF, and form
> and shape to give the appearance of the
> Zalytron cabinet called
> "Rosinante." Interested in hearing
> any opinions.

[nepaeric]

Paul, Thank you very much. I appreciate your help. Even though the MCM does not appear to model well as a candidate with promise for a TL design, looking at the results you obtained. The Dayton 7" driver seems like an attractive option. Especially being as similiar as it is to the MCM shielded driver. The 62" L, 13:1 tapered 1.5 cu ft box sounds like a plan.- Here's what I'm thinking:

As I previously mentioned, I got three of the MCM woofers and three of those Audax tweeters. I have access to the crossover components mentioned in Zaphaudio for that Dayton driver, through my brother. I have all of the cabinet building material anyone could want.

What if I just purchased 2 of the Dayton 7" drivers and two more Audax tweets? (They're not overwhelmingly expensive) I'd have 3 MCM woofs, 2 Dayton woofs, 5 Audax tweets. Then:

Build two TL's modeled around the Dayton drivers with 2 Audax tweets in keeping with your MathCad figures to use as the main pair.

Build an AS, timbre voice matched center channel using one MCM woof and one audax tweet.

Use the other two MCM drivers to build an AS surround pair ???

I'd have to assume since they are based on the same cones, (according to Zaphaudio, who highly rated both drivers) if the tweets were identical, they'd be well timbre matched, and certainly match, obviously in appearance, for aesthetic appeal.

What do you think ? Does this sound like a good plan or would you do something different ?

Also, do you have any diagrams or dimensions on that tapered line ? You have been a tremendous help! Thankyou! Regards, Eric

> I modeled this MCM driver in a short and fat
> ML-TL, a long and thin ML-TL and a tapered
> TL, using Martin King's MathCad software and
> none of them gave even reasonably good
> results AFAIC. However the Dayton DA175-8
> gave good to very good results for all three
> varieties of TLs. I really liked the results
> for a 62-inch long, 13:1 tapered TL in a
> cabinet volume of right at 1.5 cubic feet;
> F3 was ~33 Hz. Both ML-TL versions gave
> comparable results, even better in some
> other areas. I would not recommend the MCM
> driver for a TL, and the extra 7 bucks the
> DA175 would cost you is well worth it.
> Paul

[Paul K.]