Hi-Vi F series V.S. MN series (1 Viewer)

[Brian Bunge]

Darren,

Would you mind sharing with us what tweeter you're using?

 

[David Giesbrecht]

The M6N is a good driver, though it has its first breakup rather low for a 6" driver, hence making it more difficult to use in a two-way. The first breakup in the M8 series of drivers is at almost the same frequency, so if you're going to go through the trouble of making a lower XO point, you probably ought to just use the 8".

Actually I have been looking at the D8 driver and it looks promising other than the sharp peak @ 500 hz, but my plan was to mount it in a test box and test in room before making any jumps to use baffle step correction or notch filters Because who knows the response in room might be flatter without them because in the end the room messes with the response so much such attemps to make the driver perfectly flat in a test chamber may become completly null and void anyway. (my opinion but your welcome to your own)

As far as breakup modes go I was planning to cross the woofer over to a DMN dome mid @ 800 hz so that shouldn't be a problem (I hope)

When it comes to alligning voice coils and phase. I was planning to build test box's first and simply adjust the distances of the driver for max output @ the XO frequency maybe I might end up purposly misaligning the VC's to adjust for phase I figure if it works go for it.

PS my current plan is for a 3 way design using a D8 driver (5 ohm model) a DMN dome midrange and an RT1C-A Planar tweeter. Crossed over @ 800 hz and 5000 hz Powered by Hypex active home 3 way amps. (the wonderful thing about these amps is that its easy to swopp crossover frequencies.)

 

[Michael R Price]

But don't you need more than just flat response with adjustable gain between the drivers? How steep are those crossovers?

 

[Andrew Pratt]

We've have more than 1/2 dozen operational M8a variants in the pipline for almost 18 months and no one has commented that they have a metalic sound. Perhaps it's Jon's 48dB/octave XO.

Of the numerous people that have heard my M8a's no one has ever said they round it metalic sounding...in fact the work they most often use is "smooth". I had a serious audiophile over yesterday to listen to them as he was strongly considering some $4K Totems but he's now going to build a set of M8a's instead.

 

[ThomasW]

Micheal

Yeap, you're right there's a lot more to it than that.

David

The DMN is a marginal quality mid at best.

Trying to integrate point source drivers (dome mid and cone woofer) with a line source tweeter (Hi-Vi planar) is a task that baffles even the best speaker builders. And trying to do that with an off the shelf generic XO is pretty much a recipe for problems.

IMO you'd be MUCH better off making a 2-way using somewhat more expensive drivers than a 3-way with low buck drives.

I do wish you luck

Cheers,
ThomasW

 

[Brian Bunge]

Andrew,

I was looking at your site a week or so ago and couldn't find any construction pics of your towers. All I remember seeing were the original bookshelf pics.

I'd really like to see the tower construction pics if you have them. I'm considering these vs. the MTM towers that Thomas built for Tibor. Can you give me the tower dimensions as well?

 

[David Giesbrecht]

Trying to integrate point source drivers (dome mid and cone woofer) with a line source tweeter (Hi-Vi planar) is a task that baffles even the best speaker builders. And trying to do that with an off the shelf generic XO is pretty much a recipe for problems.

The only difference between the Point source and line source drivers is the fact that they disperse differently and the line source drivers only lose 3db for every doubling of the distance instead of 6db from what I understand this problem can be adjusted for with the adjustible gain on the Active Home amps.

I would become far less sceptical and more understanding if you gave me more detailed reasons why I should'nt or should do something rather than simply telling me "theres more to it than that".

 

[Brian Bunge]

David,

Thomas and his pal, Jon, have been at this longer than you and I have been alive (almost collectively). What most people may consider quality drivers doesn't necessarily mesh with their higher than usual standards. Also, you have a habit of oversimplifying things that you obviously haven't even tried yet. In this regard, I'd highly suggest you at least heed their warnings and take them into consideration. After doing so, if you still think they're full of it then take whatever course of action you want.

 

[Michael R Price]

David,

This is awfully complicated. The "textbook" active crossover in those plate amps isn't enough to make the drivers sound right, and it's pointless to use them if you'd have to also make most of a passive crossover too.

2-ways are hard enough! (They can sound pretty good, too.)

 

[ThomasW]

David

This will be my last post on the subject.

When there is a mix of line source and point source drivers the 'sweet spot' is limited to ONE fixed distance from the listener. So you can focus the drivers at 10' or 15' or 20' and the speaker will sound good at that ONE distance. It's performance will be sub optimal at all other distances. This is a function of the performance characteristics of line source vs point source speakers.

For far less than the cost in components listed; you could build the M8aMKIV, and have a proven design that is performance competitive with some pretty high dollar speakers.

The M8aMKIV as designed to provide ~80% of the performance of this $5600 Avalon Acoustics Eclipse loudspeaker when built in the stock Woodstyle rectangular box. If built in the cabinet configuration shown below, it's basically it's equal.



Please note I have no 'vested' interest in people building the speaker other than (+) feedback we have received from ALL who have built them.

Anyway whatever you build have fun

Regards
Thomas

 

[Michael R Price]

David, I know designing your own speaker is fun... but why not build the M8a design first, and then experiment with your own stuff? I mean, your first attempt is almost guaranteed to sound worse, and it would cost more too. Jon's design is the real deal.

I will soon be trying to build an active crossover for my Kit281s, and even though I am trying to suit the drivers' responses with the filters (more than standard high/low pass: nonstandard Q/frequencies, bafflestep shelving, and notch filters), I expect that I will still prefer the sound of the Adire passive version. It's just very hard to get active crossovers right (probably, equally hard as with passive crossovers). And with any custom design, you'll need to experiment with different parts a lot - takes a lot of time and costs a lot of money.

 

[David Giesbrecht]

Your right mike one of my designs probably would'nt sound as good as jon's design but then I don't get to tweek stuff I mean I don't think I would have that much fun at all building someone elses speaker. It just doesn't seem like DIY any more because all you would be building is the box and I've built plenty of speaker cabnets before. It wouldn't really be my speaker now would it, it's just exploiting somebody elses design efforts as far as I'm concerened.

 

[Michael R Price]

Well, I am just suggesting that you could perhaps build a proven design to function as your main speakers (good quality) and then maybe start cooking up your own designs.