Coming to InDIYana 2009, the Marcato...

[Paul K.]

I finished the new pair of speakers that I will take to Wolf and Brian's event in Auburn on April 18 (these will also go the the Iowa DIY event in October and to PE's DIY event if they have one again this summer). The name I chose is Marcato, which is a musical term that defines a specific way to play a note. This name isn't particularly descriptive of the speakers, I just liked the way it sounds.

This is an ML-TL (please, let's not get into any more "discussions" about what is or is not a TL ). The 7-inch midwoofers are Usher 8945Ps and cross to the tweeter, a BG Neo3PDR, at about 2400 Hz. Dan Neubecker designed the crossover from the first of the two cabinets I finished building. Dan's design is a model of elegant simplicity needing just 8 components (thanks a bunch, Dan). I modeled the ML-TL using Martin King's MathCad-based TL worksheets, of course, and the modeled F3 is 32-33 Hz, with the response down about 1/2 dB at 40 Hz.

The cabinet itself is 45" tall, 10" wide and 12-1/2" deep with the base adding 3/4" to the height and 1" to both width and depth. The baffle and top are 3/4" solid red oak, the sides are a sandwich of 1/2" solid red oak on the outside to 1/2" MDF on the inside, and the back is 3/4" oak-veenered plywood. The cabinet is extensively braced and the inside of the rear has a layer of VE-1 damping sheets. The mass-loading port has a slot shape and is located on the back near the bottom.

I applied 4 coats of oil-based Minwax gloss, "clear" polyurethane to the exterior (it isn't really clear because it has a slight orange tint). The sides and back were stained first with walnut and the baffle and top were left unstained. The first 3 coats were applied with a brush, sanding with very fine sandpaper after the first two coats, then using fine steel wool after the third coat. The 4th coat of poly was wiped on to get a really thin and smooth surface (I took a page out of Dan's book and took one photo to show the reflection of a vase in a side panel).

Dan did a super job on the crossover. I've been burning them in this week and tweaking the tweeter's attenuation (Dan and I thought they sounded a bit bright or forward when we listened to the pair a couple of weekends ago). I think I've settled on the tweeter's setup at this point. The bass is quite good, as expected (there's 3-dB of BSC incorporated), and the Usher midwoofers are excellent drivers and well worth their costs. I'm not yet able to say if or that the Marcatos come close to sounding as good as the canTiLenas because those are a really tough act to follow!

I'll attach 4 photos to this post and 3 more in another post.

[Paul K.]

Three more photos are attached. I forgot to mention what parts I used in the crossover. Resistors (2) are Mills', two of the capacitors are Jantzen Standard Z and the other cap is a Dayton Poly. The three inductors are Meniscus air-cores.

[brianpowers27]

That design looks great! I can always appreciate a speaker with a large stature. The finishing work also is a good style. It has a classic and timeless look to it. I am looking forward to hearing them soon.

[jkim]

Paul,

What a coincidence! A person plans on bringing to Iowa DIY an MT speaker with the Usher 8945P and the BG Neo3PDR. I designed a crossover for him a couple of months ago and he's in the process of building it. I believe this driver combination is very cost-effective and can rival in their performance a speaker with higher priced drive units.

-jAy

[Paul K.]

Paul,

What a coincidence! A person plans on bringing to Iowa DIY an MT speaker with the Usher 8945P and the BG Neo3PDR. I designed a crossover for him a couple of months ago and he's in the process of building it. I believe this driver combination is very cost-effective and can rival in their performance a speaker with higher priced drive units.

-jAy

It will be interesting to compare the designs to each other and unless your crossover design is super simple and the crossover parts costs are really low, we're likely to end up in the same Midrange Class as direct competitors.
Paul

[jkim]

It will be interesting to compare the designs to each other and unless your crossover design is super simple and the crossover parts costs are really low, we're likely to end up in the same Midrange Class as direct competitors.
Paul

I believe that it will also belong to the Midrange Class. A crossover for the 8945P can't be super simple due to its breakup at 3 - 4 kHz. According to your pics, Dan used very asymmetric slopes for phase matching. A first order electrical filter on the midwoofers, combined with a notch at the driver's breakup, and a third order electrical on the tweeter. The BG Neo3PDR has a steep natural rolloff below 2 kHz. So if you use a 3rd order electrical filter on the Neo3, you should use a very shallow rolloff on the woofer to obtain good phase tracking. That's what Dan did. My approach was a bit different. Still a bit asymmetric acoustic filter, but uses a 2nd order electrical with a notch filter on the midwoofer, and also a 2nd order electrical on the tweeter. Xover point is 2.1 kHz. I expect overall tonal quality will be very similar between these two designs. Your MTM will have higher power handling, of course.

[nordhaven]

Paul,

What a coincidence! A person plans on bringing to Iowa DIY an MT speaker with the Usher 8945P and the BG Neo3PDR. I designed a crossover for him a couple of months ago and he's in the process of building it. I believe this driver combination is very cost-effective and can rival in their performance a speaker with higher priced drive units.

-jAy

Paul.
I'm the guy Jay Kim is talking about bringing the 8945P & BG Neo3PDR TM to Iowa. That might help explain all the interest/questions I have had about the marcatos. It should be fun to hear the two. I have been holding off on starting the build because the parts were back ordered and my spring sinus's have my ears all messed up. I should get going here in a few weeks and will post a build thread.

[Paul K.]

That design looks great! I can always appreciate a speaker with a large stature. The finishing work also is a good style. It has a classic and timeless look to it. I am looking forward to hearing them soon.

Thanks, Brian, the photos don't really do them justice.
Paul

[Paul Carmody]

Mmm, nice name. I like it. I'm looking forward to hearing them.

This is gonna be weird at InDIYana if both you and Jay bring 8945P/Neo3 designs. Does this mean I'm supposed to bring my Scan-Speak 8545K/Neo3 too? Or will this cause us all to start having slurred vision and speech?

[Paul K.]

Mmm, nice name. I like it. I'm looking forward to hearing them.

This is gonna be weird at InDIYana if both you and Jay bring 8945P/Neo3 designs. Does this mean I'm supposed to bring my Scan-Speak 8545K/Neo3 too? Or will this cause us all to start having slurred vision and speech?

I had a really difficult time choosing a name and finally, with the help of my wife, came up with Marcato.

The similar design Jay referenced is going to the Iowa event, and Jay isn't bringing it. It's being presented by another builder for which Jay did the crossover design.

[Wolf]

I'm sure the pictures don't do them justice!

[Hmmm.... I might have to step-up on the "Propensity" (Airborne/Morel) to compete in the Midrange class this year! I'm just uncertain the "Vijon" will do well enough, but I'll let you judge that at InDIYana...]

I bet those sound fantastic, and I've been wanting to hear that driver in comparison to the SS 8545K I heard in Paul's floor-stander. I bet there isn't much lacking in the Usher drivers from the SS 7". Plus, the satin phase-plug looks neat-o!
Later,
Wolf

[jkim]

I've been wanting to hear that driver in comparison to the SS 8545K I heard in Paul's floor-stander. I bet there isn't much lacking in the Usher drivers from the SS 7". Plus, the satin phase-plug looks neat-o!

I'd compare the 8945P to the SS Revelator rather than the SS classic 7". Though the 8945P's cone and soft parts may not be up to the level of the Revelator, its motor is nothing short of high-end. It has a full length copper sleeve that runs through the entire motor gap (on a T shaped pole piece), extended to the phase plug. It's not like shorting ring(s) just above and/or below the gap like some other high-end drivers. Indeed, according to Zaph's test, the 8945P's nonlinear distortion performance is on par with or even slightly better than the 7" SS Revelator. Though not a sole indicator, the SS 8545K's impedance being higher than 16 ohms already at 10 kHz suggests that it should have even less copper/aluminum in the motor than the "A" version of the Usher.

Another nice thing about the 8945P is that despite its phase plug design, there is virtually no air leak even at very high excursion in a sealed box. Very different from what I experienced with the RS180.

For more detailed info about Usher drivers, see this:

http://www.htguide.com/forum/showpos...8&postcount=31

-jAy

[edlafontaine]

This is going to be another breakout event...

Paul Carmody posted:

Or will this cause us all to start having slurred vision and speech?

After remaining on your toes with your students for so long, you deserve some relaxation...Bring It!

[Thezeek]

Realy sweet!

[dlneubec]

Paul,

Glad to pay you back a little for all the TL help you have given me! You selected a great pairing of drivers and the bass tuning was spot on, I thought.

Just to point out what may be less than obvious here. The Neo3pdr Paul used has the rectangular mount and sits at the surface, not the round mount that has a bit of a waveguide. It has a peak in its FR on axis that is quite a bit higher at around 1800hz than what I've seen for the standard waveguide-like mount and then a very steep low end roll off. My guess is that it is due to the differences in the mounts. Attenuating that large peak in the high pass was a significant concern for the crossover design and the main reason for the higher order slope and higher crossover point used on the tweeter. Attached are my raw measurments in Pauls box on axis (pinkish) and 15º off axis (blue). For comparison, I've attached Zaphs measurments with the standard faceplate. Also of note is that Paul's crossover was designed for 15 degrees off axis listening.

Guys, this is one excellent performer, IMO and will have many builders wanting to do this one when they hear it.

BTW, where did you end up on the tweeter resistor?

[Paul K.]

I'm glad you decided to elaborate on this tweeter faceplate issue as it's better for the description to come straight from the horse's mouth, as it were, than to get a mangled description from a go-between (me). I forgot to mention in my original post that you optimized the design for the speakers to be firing straight ahead with me listening at 15 degrees or so off-axis.

Assuming I don't change it, the tweeter's attenuation resistor is at 1.5 ohms. We both heard them with the original 0.5 ohms, and I listened to them fairly extensively with 1.0 ohms, but I'm really liking them with 1.5 ohms. Nothing is missing in the highs with this value and the brightness or forwardness we heard is gone (although that one CD I played at your house that was pretty bright is instead of a crossover issue).

Paul,

Glad to pay you back a little for all the TL help you have given me! You selected a great pairing of drivers and the bass tuning was spot on, I thought.

Just to point out what may be less than obvious here. The Neo3pdr Paul used has the rectangular mount and sits at the surface, not the round mount that has a bit of a waveguide. It has a peak in its FR on axis that is quite a bit higher at around 1800hz than what I've seen for the standard waveguide-like mount and then a very steep low end roll off. My guess is that it is due to the differences in the mounts. Attenuating that large peak in the high pass was a significant concern for the crossover design and the main reason for the higher order slope and higher crossover point used on the tweeter. Attached are my raw measurments in Pauls box on axis (pinkish) and 15º off axis (blue). For comparison, I've attached Zaphs measurments with the standard faceplate. Also of note is that Paul's crossover was designed for 15 degrees off axis listening.

Guys, this is one excellent performer, IMO and will have many builders wanting to do this one when they hear it.

BTW, where did you end up on the tweeter resistor?

[Paul K.]

I appreciate all of the compliments and I'm looking forward with great anticipation of bringing the Marcato to InDIYana 2009 and hearing everyone else's creations.
Paul

[Paul K.]

The 1/2" solid red oak side claddings were sourced from Ed LaFontaine. Ed is an excellent wordworker (remember his entries at PE's event last year?). For the Marcato, he cut strips of the oak, planing them to their 1/2" thickness somewhere in the process, squared their edges, glued them together, cut them to the final size I needed, and sanded one side down to almost its final needed finish. All I had to do was round over 3 edges on each piece, do a little final sanding, then proceeded with staining and applying polyurethane before gluing them to the 1/2" MDF inner side panels. Ed charged me for materials and shipping, donating his time for making them, and I thank Ed for this because it would have been very difficult for me to do the same thing, and I certainly couldn't have done as good as a job. Ed's contribution to the Marcato is just another of many examples sharing we all have opportunities for in this hobby. Mucho thanks, Ed!
Paul

[robert]

Paul, they look great (very traditional) and I am looking forward to hearing them at Iowa! I still have 2 of the 9.5" Audax woofers left and may try and knock out that ML-TQWT you designed for me when I get back from this endless trip.

Sadly my HiVi Seas design is topping out in the bottom of the mid category (around 300.00) so I'll be in that group. And the F8 is going to require some fairly serious inductance...

Robert

[Paul K.]

Thanks, Robert, for the compliments. BTW, the bottom end of the Midrange Class at Iowa is $350 and if you can keep the cost of your HiVi/Seas design under that, they'll be in the Budget Class. Does that make you feel any better?
Paul

Paul, they look great (very traditional) and I am looking forward to hearing them at Iowa! I still have 2 of the 9.5" Audax woofers left and may try and knock out that ML-TQWT you designed for me when I get back from this endless trip.

Sadly my HiVi Seas design is topping out in the bottom of the mid category (around 300.00) so I'll be in that group. And the F8 is going to require some fairly serious inductance...

Robert