M8ta - Listening Impressions??

[ThomasW]

Hey! Now they're beginning to look heavy....:wink:

[cjd]

Hey! Now they're beginning to look heavy....:wink:

better be careful, women usually don't like hearing that.

Or did you mean the speakers?

C

[ColoradoTom]

Word of caution.....

Hey! Now they're beginning to look heavy....:wink:

I found out what a liability the weight can be...

While working out some issues with the placement of the vent, one of the clamped cabinets dropped out of my hands and "floated" about a half foot to the ground crushing one of the corners! Had to whip up another one with some spare glued parts. Since I'm out of spare parts I won't be doing THAT again.

[ColoradoTom]

Hope I don't go too much offtopic but I saw that finish and I was wonder what do you guys say about this one?
The first picture looks better than the sample!
They say it's called Myrtle Cluster Burl! How much do you think it costs?

Thanks!

I would guess a minimum of about $3.00 US per square foot. You'll also have to deal with it not being flat and you often have to match several pieces together to cover a large area like a side panel - I'm not sure it's something I'd try my first time veneering.

[BobEllis]

OT - Daughters

Cute kid!!

Mine are growing up too fast.... I kinda wish I could skip right through the puberty/teen stuff though. My oldest is already in the hormonal stage - one minute she's an angel the next she's......... her EVIL TWIN!!!

Tom

Don't worry Tom, I have it on reliable authority that most girls regain their sanity somewhere in their mid twenties. Mine's only got 5-6 more years

[ColoradoTom]

Don't worry Tom, I have it on reliable authority that most girls regain their sanity somewhere in their mid twenties. Mine's only got 5-6 more years

I'm hoping for short term memory loss during thier upcoming teen years!! Actually 99.9% of the time they are the sweetest kids you could imagine - of course I'm not biased in my opinion at all!!!

[JonMarsh]

I found out what a liability the weight can be...

While working out some issues with the placement of the vent, one of the clamped cabinets dropped out of my hands and "floated" about a half foot to the ground crushing one of the corners! Had to whip up another one with some spare glued parts. Since I'm out of spare parts I won't be doing THAT again.

Don't feel bad- I've done the same thing with a big toe before- not very funny.

It does take some care and deliberate moves. Just wait till you get them mostly together and a veneering- that's when the real paranoia starts!

[ColoradoTom]

Question for Jon/ThomasW

Hey Guys.........

I'm not sure if either of you can answer this for me, but here goes. The crossover portion is probably going to be the hardest part of this build for me. I have a Pass Labs XVR1 crossover which is the most transparent electronic crossover I've used. It allows slopes of up to 24db as well as adjustment of the Q at the crossover point.

Question: Should I be able to get a reasonable estimate of the "sound" of the M8ta using an electronic crossover and matching the slopes of the passive crossover that was originally designed by Jon??

Thanks for the help......

Tom

[cjd]

Considering the original slopes are ~48dB/oct, ...

Though, if you can add notch filters on top of a 24dB slope it'll probably be fine since that's vaguely how the C-E filters work. Maybe not simple.

Might be able to find someone willing to assemble a passive for you if that's the worry. . .

C

[ThomasW]

Tom,

You can certainly play with the Pass, but it won't have the baffle step, zobel and other stuff Jon puts in the passive XO.

We can probably assemble the XO in an afternoon if you want to drop by...

With a little help you'll find that assembling the XO is the easiest part of this entire project....:wink:

[ColoradoTom]

Tom,

You can certainly play with the Pass, but it won't have the baffle step, zobel and other stuff Jon puts in the passive XO.

We can probably assemble the XO in an afternoon if you want to drop by...

With a little help you'll find that assembling the XO is the easiest part of this entire project....:wink:

Well, I figured I could approximate the BSC with the volume on the high pass but knew that the higher slope and zobel might be a problem.

Thanks for the offer...... I can supply sandwiches from the NY Deli News. My only concern is that you'll tell Jon that I wimped out on the North Creek Inductors and went with Solen Perfect Lay. I figured if the word got out someone may revoke my "DIY man license"!!

I'm pretty sure I've got all the parts in house - I'll run a check to be sure and then maybe we can set something up in the next month or so.

Thanks..........

Tom

[ThomasW]

My only concern is that you'll tell Jon that I wimped out on the North Creek Inductors and went with Solen Perfect Lay. I figured if the word got out someone may revoke my "DIY man license"

Oh, no! 8O

Well okay, you get a free pass since this is your first project and it's such an ambitious one. BUT when you upgrade to the Isis clones ...:wink:

The Woodcraft store on I-225 at DTC Blvd has these roller stands on sale. I picked up a pair to use in the shop. They're really cool..... :T

[ColoradoTom]

Oh, no! 8O

Well okay, you get a free pass since this is your first project and it's such an ambitious one. BUT when you upgrade to the Isis clones ...:wink:

The Woodcraft store on I-225 at DTC Blvd has these roller stands on sale. I picked up a pair to use in the shop. They're really cool..... :T

Oh Yeah..... just what I need is more woodworking crap in the garage!! I've got so much going on with this DIY project that the only car that gets regular time in the garage is my wife's car (for obvious reasons). My car and the POS minivan have been banished to the driveway for the past three weeks.

On the other hand (mind working on how to convince wife I really need this), I do work alone quite often.. and $200.00 isn't much to pay for the increased safety it would provide... and those roller stands fold up so nice and compact... yup, I think this is going to work!

[ThomasW]

FIY they weigh 90lbs ea.

If you go to buy one you're about 3 minutes from my place.

[ColoradoTom]

FIY they weigh 90lbs ea.

If you go to buy one you're about 3 minutes from my place.

90lbs... no problem - good practice for lifting these M8ta's which should end up weighing double that!! 8O

Could try to check them out this weekend if my schedule allows - but right I'm booked solid from Thursday morning through Sunday night. Normally how this works for me is my first chance to get over there is one day after the special ends!! :roll:

[ThomasW]

You can phone order with your CC. They had 3 left as of yesterday, but will order more at the sale price. They were out when I went to get my second one, my special order came in 1 week later.

I was worried that they would be flimsey, they aren't...

[BobEllis]

Well, I figured I could approximate the BSC with the volume on the high pass but knew that the higher slope and zobel might be a problem.

Thanks for the offer...... I can supply sandwiches from the NY Deli News. My only concern is that you'll tell Jon that I wimped out on the North Creek Inductors and went with Solen Perfect Lay. I figured if the word got out someone may revoke my "DIY man license"!!

I'm pretty sure I've got all the parts in house - I'll run a check to be sure and then maybe we can set something up in the next month or so.

Thanks..........

Tom

One of the advantages of the Pass XVR-1 crossover has compared to the usual commercial analog crossover is that each filter pole is individually adjustable. The gain of each 2 pole section is adjustable as well. You can get pretty close to proper baffle step compensation by setting one low pass pole near the baffle step center frequency and using the remaining poles for the crossover, as long as your crossover frequency isn't too much above the baffle step frequency. It's a lot more flexible than you'd think.

[ColoradoTom]

One of the advantages of the Pass XVR-1 crossover has compared to the usual commercial analog crossover is that each filter pole is individually adjustable. The gain of each 2 pole section is adjustable as well. You can get pretty close to proper baffle step compensation by setting one low pass pole near the baffle step center frequency and using the remaining poles for the crossover, as long as your crossover frequency isn't too much above the baffle step frequency. It's a lot more flexible than you'd think.

Thanks Bob.....

I had a little voice inside of me thinking the "ultimate" M8ta might be a version that was bi-amped. Since I already have the XVR-1 and more amps than any reasonable person should have, I thought it might be fun. I also thought that I'd probably have the cabinets done several weeks before I got around to the crossovers - this may not be the case as I may be able to bribe ThomasW into lending me some help!!!

Tom

[gimpy]

Jon, your daughter doesn't look anything like your picture. But I think that's good.

Frank

[JonMarsh]

Jon, your daughter doesn't look anything like your picture. But I think that's good.

Frank

Yes, it is. It's also good that I don't look anything like her....

She strongly resembles a great aunt on my mother's side of the family, and aside from that, pictures of her and myself when we were 5-6 look like we'd be siblings. Very similar shap at that age to forehead, nose, jawline. But she, like almost everyone else in the family on both sides, is vertically challenged, whereas I'm 6'2". Not sure how that happened, except for my maternal grandfather.

[cjd]

I had a little voice inside of me thinking the "ultimate" M8ta might be a version that was bi-amped.

You can bi-amp most passive crossovers too.

There are many discussions about active, including how to emulate the steeper slopes it takes to really get a design like this to come together. You'll also discover use of passive crossovers is intentional on Jon's part.

Have fun with it, regardless.

C

[ColoradoTom]

Facet Jig

I did some thinking and came up with a simpler version of the original jig I built. Basically, as you can see from the pictures, it's a partical board platform with a 45 degree incline. I use it in combination with a tapering jig and it allows you to cut any reasonable angle for the speaker facets. The tapering jig I have lets you to use it with either side running along a straightedge and so the same jig cuts both sides of the baffle without any modification. The nice thing is that the cuts are very accurate and your hands/fingers are nowhere near the saw blade (which is extended to full height). The final picture show the results.

Tom

[dyazdani]

Looks great Tom, I think I will be forced to try my own way. I will just have to experiment. I've got a while to wait anyhow...

[ThomasW]

Tom, you're a clever lad....

Very simple and effective design ... :T

[JoshK]

You just made this project a whole lot more accessible to the rest of us.

[JonMarsh]

Facet Jig

I did some thinking and came up with a simpler version of the original jig I built. Basically, as you can see from the pictures, it's a partical board platform with a 45 degree incline. I use it in combination with a tapering jig and it allows you to cut any reasonable angle for the speaker facets. The tapering jig I have lets you to use it with either side running along a straightedge and so the same jig cuts both sides of the baffle without any modification. The nice thing is that the cuts are very accurate and your hands/fingers are nowhere near the saw blade (which is extended to full height). The final picture show the results.

Tom

:T :yesnod: :agree:

[cjd]

Having a hand out of commission still from a table saw injury (featherboards are your friends!), I want to point out the block of wood holding the angle on the taper jig. With the amount of mass in this setup, I think this is key, since it will hold things that much more stable.

Very nice jig. I wish I has access to one of those roller tables. Slick!

C

[ThomasW]

Very nice jig. I wish I has access to one of those roller tables. Slick!

Woodcraft is a nation wide chain/franchise and they sell online. Down side to mail order is the 90lb shipping weight.

Hope your hand heals up soon...... :T

[ColoradoTom]

Having a hand out of commission still from a table saw injury (featherboards are your friends!), I want to point out the block of wood holding the angle on the taper jig. With the amount of mass in this setup, I think this is key, since it will hold things that much more stable.

Very nice jig. I wish I has access to one of those roller tables. Slick!

C

Actually, I completely forgot about mentioning that wedge. I do it all the time so I don't even think about it any more. Once you have the angle set up on the tapering jig you can easily cut a wedge out of scrap wood. I then register the wedge to the back of the taper jig so that it aligns exactly with the back edge of the jig and cut it to length. Now, as cjd stated, the tapering jig is much more stable and cannot close up from pressure. An additional side benefit is that you now have a means of creating the exact angle again by placing the wedge back into the jig and aligning the wedge to the same point on the back edge of the jig.

Another thing you need to be careful about is that you always register the piece to be cut to the same point on the sled (I use the back edge of the 45 degree angled piece of the sled). This will make the cuts on each facet match perfectly. I made the mistake of rushing things yesterday to get to a family event and didn't take the time to align the baffle to the back of the sled on one of the cuts - I was forced to create a "patch" on one baffle to repair the cut that I started in the wrong place. On complicated cuts I also draw a line where the cut will intersect each face - this is how I knew I was making a bad cut and prevented me from making an unrecoverable mistake.

Hope that all makes sense...... if it doesn't, well, it may be the margaritas I had last night talking!!

Tom

[ColoradoTom]

Things have been slow in terms of progress on the speakers, too much family & work stuff the past month! I did get a chance to meet ThomasW (great guy!) at his place over the weekend and attemped to get some work done on the crossovers, but we actually spent more time talking than getting any work done!! He did provided me with enough training to get things moving along so I hope to post some progress with text and pictures over the next few weeks. THANKS again Thomas!! ;x(

Thomas has convinced me that my path to true audio happiness is to either take the leap of faith and build an ultimate dipole or to suck up to he and Jon and co-create an Isis clone!! Now, I feel pretty confident in my "sucking up" skills.... but my speaker building/designing skills have a long ways to go before either of those options will happen! :E

Tom

[ColoradoTom]

Wasn't it John Lennon that said:

"Life is what happens while you're busy making other plans"

Well I've been planning on getting back to work on this project for what seems like forever!!

Between work, sports and family commitments thing haven't been going so well. Oh by-the-way, last time I posted I mentioned that my family was in tennis playoffs - well I didn't do so well but my girls came in second in the State!

Yesterday was the first time since about May/June that I have been able to do some work on my M8ta's. I was able to get the cabinets assembled and I'm preparing the front baffels for final glue-up this weekend. At the rate I'm going I should have them done just about the time ........ that Jon posts here again!! 8O

I have been lurking about here when I get a chance and have joined the group of Infinitly Baffeled - eyeing the possibilty of another future DIY project.

ThomasW - still hope to get you over to the house to listen to the Sound Lab M1's as things usually start to slow down in our business towards the end of the year. Will post some pictures of my progress if I get a chance this weekend.

ColoradoTom

[ThomasW]

Hi,

If all goes as planned, Jon will be posting from my house around the 5th through the 11th of Oct... :T

So perhaps we can all get together .

[ColoradoTom]

Hi,

If all goes as planned, Jon will be posting from my house around the 5th through the 11th of Oct... :T

So perhaps we can all get together .

Whoops..... I guess that means I have to have the speakers done by then!! :E

[ColoradoTom]

Update with pictures

Been doing work whenever I can squeeze it in between family and job. I tested some inserts to hold the mid/bass driver in place. There is a picture of the insert as well as a test of the implementation. They are a little different from T-Nuts as they screw into the MDF - with a little epoxy added to the insert it creates a very strong grip and requires a lot of effort to unseat allowing one to tighten the screws attaching the driver to a more than reasonable amount.

I also added pictures of the finished cabinets. I will be placing Wispermat along backs and sides, inserting the port and stuffing with polyfill this weekend! If all goes well I might even get in a test listen to them next weekend.

Tom

[ThomasW]

Interesting I have need to use something like those, and was wondering how they'd work.

If all goes well I might even get in a test listen to them next weekend.

Cool, you can get a demo room at the RMAF.... :B

[ColoradoTom]

Interesting I have need to use something like those, and was wondering how they'd work.

Cool, you can get a demo room at the RMAF.... :B

Well... as weird as this may sound I found them at Home Depot a few weeks ago and thought that they looked like they would do the job. You pre-drill the MDF and then just screw them in. The epoxy probably isn't necessary, but I like to be sure that they won't come loose. I tested them pretty hard and they didn't fail.

I'm thinking of going to RMAF... I'll be all alone for the day with no "Honey Do's". Wouldn't be too much trouble since it is on our side of town!!

Tom

[ThomasW]

Let's get together and check it out.

What's your free day?

[ColoradoTom]

Let's get together and check it out.

What's your free day?

Saturday or Sunday are good for me... probably the most crowded days, but next Friday is going to be a busy work day for me and I doubt I could get away.

Let me know if one of these days works for you.

Tom

[ColoradoTom]

Expandable Foam

Quick question - does it make sense to secure the port internally using the expandable foam used for insulation? I have some lying around and got to thinking that it might be a good idea to keep the port secured against the internal braces using expandable foam between the port and the brace. I was originally just going to stuff some polyfil around it. Thanks for any help.

Tom

[wkhanna]

Let's get together and check it out.

You get to hang with the Maestro!

I am Sooooo jealous!

[ColoradoTom]

Getting Closer!!!

Veneering underway and almost completed. Building the crossovers this week... hope to test by the weekend! ThomasW has tormented me with a new project involving Aura 12" woofer columns - four drivers per side. 8O Details to follow!!

[mmoeller]

ThomasW has tormented me with a new project involving Aura 12" woofer columns - four drivers per side. 8O Details to follow!!

:E ;x(

[ThomasW]

Veneering underway and almost completed. Building the crossovers this week... hope to test by the weekend!

We'll keep our fingers crossed, give me a holler if you need to trouble shoot anything .... :T

ThomasW has tormented me with a new project involving Aura 12" woofer columns - four drivers per side. 8O Details to follow!!

I'm always a bad influence, and proud of it...

[ColoradoTom]

We'll keep our fingers crossed, give me a holler if you need to trouble shoot anything .... :T
I'm always a bad influence, and proud of it...

Tom - thanks for the offer of help. I'll see if I can get things figured out myself and if I run into trouble I'll give you a call.

BTW - the RMAF was a bad influence on me. After hearing the Kimber/Sound Lab setup with Pass amplification I felt that it might be worth investigating. Well, Christmas came early to my audio room and I now have a pair of Pass X600's and a X350. :E I'll try to get you over to the house some time in December.

Tom

[ThomasW]

Well, Christmas came early to my audio room and I now have a pair of Pass X600's and a X350. :E I'll try to get you over to the house some time in December.

Tom

Pass Amps.....:drool:

But Hey! When are you going to stop being such a piker and step up to the plate for some Boulder 2050 Mono blocks? ...... :wedgie: