Maurbacs NS6 MTM

[donradick]

Re: Maurbacs NS6 MTM

Don, and eveveryone,
What is your thoughts/opinions on the front baffle of the Maurbac being widened to around 13.5". I know this may change the BSC. The reason for the change is to allow for more volume to accomodate the subwoofer. I have ports for the NS6s, but was really thinging of leaving them sealed. I am trying to keep the sub in the tower due to room layout. I really have no where esle to place the sub.

I totally understand about space issues!!!
You're right, changing BSC would mean a total crossover rework. There are a couple of alternatives:

Build a sub "bin" or speaker stand, and put the Maurbacs (as a separate build) on top.
For one thing, they will be easier to move.

Build a tower with the same width as the original Maurbacs, but mount the sub on the side, and
make them about 15 inches deep or so, and you can put a side-firing 12 inch sub there.

In either case, I'd def make them sealed. You can probably drop the volume down to about 28 Liters
if that form factor works for you.

Have fun!

[Zayne]

Re: Maurbacs NS6 MTM

Don, and eveveryone,
What is your thoughts/opinions on the front baffle of the Maurbac being widened to around 13.5". I know this may change the BSC. The reason for the change is to allow for more volume to accomodate the subwoofer. I have ports for the NS6s, but was really thinging of leaving them sealed. I am trying to keep the sub in the tower due to room layout. I really have no where esle to place the sub.

[donradick]

Re: Maurbacs NS6 MTM

So all the parts have arrived! I went with two SD-270 10" subs, one for each side. They will each have their own plate amp.

So my next question, I am assuming it would be best to go ahead and go with the sealed cabinet. With this in mind, do I need to do any low end cutoff on the NS6's or let the natural 70ish F3 be? The plate amp does not have a high pass built in.

I'd make them ported and stuff the ports with a t-shirt - in the future, you could use them ported somewhere, and use the SD-270s with another speaker - but it's totally your choice. You don't need a high pass filter, the natural rolloff of a sealed box will be fine.

[Zayne]

Re: Maurbacs NS6 MTM

So all the parts have arrived! I went with two SD-270 10" subs, one for each side. They will each have their own plate amp.

So my next question, I am assuming it would be best to go ahead and go with the sealed cabinet. With this in mind, do I need to do any low end cutoff on the NS6's or let the natural 70ish F3 be? The plate amp does not have a high pass built in.

[donradick]

Re: Maurbacs NS6 MTM

Hello All,
I realize this is an older thread, but I am looking at building a pair of the Maurbacs since I got a deal on some NOS NS6s. My question to you all is, what are your thoughts of incorporating a woofer or subwoofer into the cabinets, I wanted to raise the listening position as well, to handle the bottom end. My thoughts are to utilize a 8" or 10" per cabinet. Originally i was leaning towards the SD125 DVC 8", but I an concerned about the Maurbacs being a 4 ohm load and then adding another 4 ohm load to the amp's B side. The crossover could be adjusted to cut off the NS6s, and possibly adjust the impedance, but it still seams like a heavy load. My other thought is the DC200-8 8" Classic Woofer or possibly the DC250-8 10" Classic Woofer. Since I have not actually heard the Maurbacs, does anyone have an opinion, suggestion, or idea as to how to approach this endeavor.

Good idea!

I never really looked at the closed box sims in Unibox.
In 34 L closed box, I get an F3 of 73, and it can handle peaks will into the 100 dB range.


As discussed, you will not be able to cross them passively, you'll need a plate amp for the bottom end driver,
because the MTM is so efficient:




I"m not a great woofer authority, but I've been looking at this woofer for a few projects:
grs-12sw-4-12-poly--sub-292-484

Looks a bit better than many of the alternatives, and at a great price.
Have fun and post some pics!

[Adam_G]

Re: Maurbacs NS6 MTM

If I were to build them again, I would put in an active subwoofer in the base of the cabinets for home theater, either with a plate amp or with an external subwoofer amp. I wouldn't try to passively cross them over to a subwoofer driver due to the efficiency difference.

[Zayne]

Re: Maurbacs NS6 MTM

Hello All,
I realize this is an older thread, but I am looking at building a pair of the Maurbacs since I got a deal on some NOS NS6s. My question to you all is, what are your thoughts of incorporating a woofer or subwoofer into the cabinets, I wanted to raise the listening position as well, to handle the bottom end. My thoughts are to utilize a 8" or 10" per cabinet. Originally i was leaning towards the SD125 DVC 8", but I an concerned about the Maurbacs being a 4 ohm load and then adding another 4 ohm load to the amp's B side. The crossover could be adjusted to cut off the NS6s, and possibly adjust the impedance, but it still seams like a heavy load. My other thought is the DC200-8 8" Classic Woofer or possibly the DC250-8 10" Classic Woofer. Since I have not actually heard the Maurbacs, does anyone have an opinion, suggestion, or idea as to how to approach this endeavor.

[WernerM]

Re: Maurbacs NS6 MTM

I just wanted to take a moment to say how impressed I am with this 2-way design Don. You did an excellent job with the crossover. I too think the tweeter may be a little hot, but it isn't fatiguing. I hooked up a CD player to them Saturday, and sat down to do some critical listening to tracks I am familiar with. I honestly feel these are just as good as many 3-ways, only lacking in the chest thump that a larger woofer provides. To me the downfall of most commercial 2-ways is definitely the lack of presence of the midrange around the crossover. These without a doubt do NOT fail in that category. The dcr tower really brings out the low bass, but it doesn't over power the midrange or highs. Yesterday I had them turned up to around 85-90dB (guesstimate), and I couldn't hear any stress in the woofers. Hell I had walls vibrating! Very nice job, and to anybody whom has these drivers, I highly recommend the dcr tower. You can find the details of my build in my Sig.

Don thank you for a wonderful design. Keep em' coming!

[rdv]

Re: Maurbacs NS6 MTM

Yes, it is a dangerous thing to start listening to a good design with the drivers mounted in an unfinished box! Sometimes it takes years for the finishing to occur.;)

I know! I do hear some resonance from my cabinet so thats some incentive for me to open them up to add bracing then finish them.

By the way, my friend gave them a listen and was hooked. he wants to build one for his house. I just posted a WTB in the classifieds.

[thekorvers]

Re: Maurbacs NS6 MTM

couldnt stop myself from grinning. i cant wait to get home from work to listen to them again. now my problem is that i have to take them apart to finish the box! i dont think that will be anytime soon!

Yes, it is a dangerous thing to start listening to a good design with the drivers mounted in an unfinished box! Sometimes it takes years for the finishing to occur.;)

[rdv]

Re: Maurbacs NS6 MTM

well with or without break in they sounded really good as soon as i turned them on. one thing i did notice was vocalists were not as defined as i expected so that may improve with break in. the speakers were also pretty far apart so that may be another reason. still overall they are a pleasure to listen to.

oh yes, one thing that came to my mind while i was listening to them, i thought they sounded like the fostex folded horn kit that i demoed at madisound's scratch and dent sale a while back. that kit impressed me but was just too pricey, specially if you include the cost of their tube amp. i can now say i have that sound for much less and diy at that.

i dont think i will be lowering the tweeter level, at least based on my listening last night. ill try some other genres later.

as for pics, im afraid my cabinets are not very pretty, specially after seeing the other builds here. i will post a pic but it wont be a detailed close-up hehe

thanks!

[donradick]

Re: Maurbacs NS6 MTM

so i finally assembled my maurbacs last night, i couldnt wait to finish the box so i just mounted the drivers and powered them up. you really did good Don, the speakers sound fantastic! they sound really open and with plenty of air. the bass is good and i am getting good bass drum thump. i initially found the tweeters 'hot' when i was testing my crossovers but once installed they are fine. they could be lowered a teeny bit but its not really necessary as they sound smooth enough for me. my enclosure is still the oversized one i mentioned earlier - 2.7cu.ft. with a 3"X3" port. drivers are not flush mounted. i am still listening for mudiness but so far i dont hear anything offensive.

have them connected to my jolida with cds playing off a really old teac. i couldn't get past half the volume control as i was afraid of waking up the wife and kids. i played some chesky albums, norah jones, rickie lee jones and some other pop albums and couldnt stop myself from grinning. i cant wait to get home from work to listen to them again. now my problem is that i have to take them apart to finish the box! i dont think that will be anytime soon!

thanks again Don for this great design!

I'm so happy you're enjoying them!
The woofers will tkae several hours of playing to break in, and yu will find the bass getting fuller
and the mid range getting a bit more clear. If you still find them a bit too bright, you can change the
tweeter resistor to a 3 ohm. The NS6s paper cones reproduce bass, piano and voices beautifully.
Be sure to post some pics of your build sometime.

[rdv]

Re: Maurbacs NS6 MTM

so i finally assembled my maurbacs last night, i couldnt wait to finish the box so i just mounted the drivers and powered them up. you really did good Don, the speakers sound fantastic! they sound really open and with plenty of air. the bass is good and i am getting good bass drum thump. i initially found the tweeters 'hot' when i was testing my crossovers but once installed they are fine. they could be lowered a teeny bit but its not really necessary as they sound smooth enough for me. my enclosure is still the oversized one i mentioned earlier - 2.7cu.ft. with a 3"X3" port. drivers are not flush mounted. i am still listening for mudiness but so far i dont hear anything offensive.

have them connected to my jolida with cds playing off a really old teac. i couldn't get past half the volume control as i was afraid of waking up the wife and kids. i played some chesky albums, norah jones, rickie lee jones and some other pop albums and couldnt stop myself from grinning. i cant wait to get home from work to listen to them again. now my problem is that i have to take them apart to finish the box! i dont think that will be anytime soon!

thanks again Don for this great design!

[donradick]

Re: Maurbacs NS6 MTM

@Werner -

Man, that looks like a sweet package. Bryan is due for some instant (good) karma.
Take your time on the build. Hopefully you learned a bit on your first one.

[WernerM]

Re: Maurbacs NS6 MTM

Well looky, looky, looky at what just came in the mail today! Thanks to Bryan, I am going to be able to attempt a DCR Maurbacs tower after all!!! :D



Progress will be a little slow, but it should be well worth it!