Speakers around the £3.5k mark

Joel, excellent post. I've personally never tried an array of 6" cones but, given both the cost and cabinet required to house them, I cannot really see the point.

And as Joel says, it's not really about extension at all, it's about giving instruments lifelike weight and presence. Most musical energy is centred between 100hz and 400hz. In this area, a big 15" will perform with an ease and authenicity that leaves modern speakers breathless.

 

Havent macintosh gone this route?

I imagine the main advantage comes from improved linearity.

 

I heard the Mac line array's at the heathrow show.

An amazing number of drive units, and a truly vast speaker.

It would be great to hear them in a more reasonable sized room (if they could fit through the door!)

 

From 4- or 6-inch drivers?
The reasoning behind these super line arrays seems to have to do with ideas about phase and wide dispersion.
I've heard line arrays from the Japanese company Taguchi many times, and they do sound quite good over a large area. Realistically, they need subs for output below about 120Hz, though.

 

With such a huge number of drivers they barely need to move so they should be operating within a more linear regime. Even with 6" drivers if you have enough of them. Line arrays bring benefits of their own of course.

 

I understand the McIn speakers are optimised for flat power delivery rather than strictly flat in-room response, but apparently the point of the array is to get speakers that take the room out of the equation to a great extent by controlling vertical dispersion (Ihave no idea how this is achieved, but the measurements speak for themseleves ) and do away with phase issues at least until the tweeter xover point. Or something like that.
But they are very large and very expensive and vastly impractical for most people. The Rey Audio Vertical Twins Merlin linked to above seem almost practical in comparison - and you can squeeze them into a surpprisingly small space (as one Japanese audio reviewer / jazz bassist does).

 

I think a good analogy here would be "why buy shoes that are bigger than your feet?".

When it comes to DIY, what we really need on this forum is folks who talk less and build more. Only then do we really understand what the difference between the words and theory are in relation to what really matters.

 

It seems you are an anti-platonist!

 

Good point Shin - how are you getting on with your latest project?

 

Well I played around with the Manger in sealed and open baffle, didn't like so am making preparations to build and investigate another avenue.

This is pretty much what I always do, try out idea's see if they will work within my tastes/needs and re-iterate through each stage until you have something your happy with, its the only sure fire way of working and no amount of discussion will give you the insight and practical experience. Its also why my projects take forever to complete. All this hardwork is experience though which is why I tend scratch my head at comments that profess one technique or route to offer a sure way of getting one on up on another path. Thorsten was good at that and it seems others are too.

When reading some of the opinions here its quite clear we aren't getting the whole picture just the selective upshots of particular design ideal.

 

I don't get your point. You are preparing to start a new project by discussing it on the forum. Like everyone else. Are you suggesting you have vastly more experience than others? Based on what?

To date, all we have seen from you is a copy of an ATC SCM50 in a pretty box which you showed details of just prior to off loading them on the internet.

So people use internet forums to discuss ideas, and others reported findings. Is that so bad. Who knows what's been played around with and not reported by some of us ;-)

 

Ah I see your original question of "how are you getting on with your latest project?" was a rhetorical one, silly me.

What I find baffling is comments like "hifi starts with a 12" midrange" which was the point behind my post above. It shows a naivety that isn't part of any serious discussion on the merits of loudspeaker design. And yes I have a fair amount of DIY experience. I've built plenty of designs that didn't work particularly well and I've built ones that sounded good too.

I think you do a disservice to that particular design by stating it as an SCM50 ripoff. Your obviously not privy to all the details but you do know that I find ATC's implementation underachieving. So clearly the two speakers sound different and the design specifics are polar opposites in some cases. I can only think of one common factor the SCM50 and my design share - the ATC mid. The rest is different.

Come to think of it your comment is flat out stupid actually. It's tantamount to saying that a design featuring driver X is a copy of another design featuring a similar driver X lineup. Again though its your usual form as evidenced in the past and with that ribbon comment a couple of pages back in this very thread.

You'll break your back to make an argument and come across as someone who knows his stuff. I've read enough of your posts to know just how to take your advice and criticism now and its usually with a big pinch of salt. Very rarely are your post non self serving, be that from putting down other folks or glorifying whatever is your opinion/experience.

After our little fray a couple of months back I seem to remember you saying you'd follow my posts and bring justice to the halls of high fidelity. Its somewhat sad that I find myself inadvertently returning the favor.

 

Shin,

It's not self serving to ask you to explain your need to insult another poster and to point out that you are guilty of exactly the same behavior as them. FWIW, I would say that the comments you took exception to contain a fair degree of truth and maybe you could experiment with running large drive units up to 800hz before taking issue with the poster concerned.

I didn't use the term ripoff - you did but let's look shall we. You used an ATC SCM150 dome along with SC Bass unit - the 9" from the ATCSCM50ASL. You used a Scanspeak tweeter rather than the Vifa no doubt because your friends on DIYAudio told you it was great (It isn't actually IMHO but that's another story).

The cabinet dimensions and port loading were as in the SCM50ASL - prettied up to make an interesting design statement. Rather than building proper crossovers, you bought a DEQX and fiddled with you computer until you liked the sound. That's somewhat different to designing analogue crossovers where an element of knowledge and expertise is required to get sometimes spectacular results. Crossover design with DEQX takes 2 minutes and could be done by anyone on this forum familiar with a Windows computer.

So I would say my point about you copying an SCM50 would be fair - and not cause for embarrassment. I too will copy proven designs. To assume that I can better the work of reverred audio engineers to to be foolhardy in the extreme. I guess that's the self serving bit But it's factual.

 

Alternatively, perhaps it's a comment from experience (in fact, I know it is exactly that).

One I agree with, as it happens. Again, from experience. It's a generalisation, but contains a large pinch of truth.

-- Ian

 

Or better still - two 12" drivers!

Or a larger number of smaller drivers.

Have you considered pmc ib1s shin?

 

The fewer drivers the better, IME.

-- Ian

 

I am so sorry about that. :SLEEP:

Just how many details can you get wrong in one post? I suggest if you don't know enough to talk about something then probably best to keep quiet.

This isn't the mobile phone business where a fat mouth, a modicum of information and a burning desire for commission win you points. Sorry was I ill informed and that isn't the case? I should've kept my gob shut then. I find it some telling that your so scant on the specifics yet feel qualified to state a design as a "copy".

So its not ported but sealed, doesn't use the same bass driver (SB vs. SL) and the cabinet whilst it may look pretty was in actual fact thoroughly aimed at better sound - non parallel walls throughout to combat standing waves, 4" thick baffles, laminated 9+18mm composite construction to reduce cabinet resonances, matrix bracing for the bass, a conscious effort to keep all internal skin panel sizes as small as possible in order to raise resonance frequencies where possible for the bass, decoupled baffles with bitumen and sorbothane isolation and 8mm thick bitumen panels throughout the internals for damping. So clearly not just a "pretty" cabinet, the fact that each speaker weighed over 75Kg should tell you that they were more than that.

I also spent much time experimenting with a passive XO implementation including a nice sounding series one that I was fairly happy with. Fact was those particular drivers sound better with steep slopes(ATC mid related) that only digital can offer. Another trick is to identify what is and what isn't the best route for the particular design your working on. I wouldn't be so narrow minded as to only use passive implementations, sometimes things just plain sound better on the alternatives, again this come down to the design and in this case it was suitably better so the DEQX won out. And yes a fool could use one of those and still get 50%+ out of the drivers they're using. However I suggest buying a Behringer DCX if all your doing is using the auto setup function on the DEQX because your wasting your money otherwise. The PC XO setup is an entirely different matter, better sounding than the DEQX but requires much more knowledge to properly harness and certainly a very solid grounding in the theory of loudspeaker design, PC knowhow and how to take accurate measurements - there's no hit an 'auto' button miracle on the PC. Its more indepth and requires more knowledge than designing passive XO's but once you've mastered it then it allows you to accomplish a fully realised XO in short time, it can also be used to prototype for passive XO's in a fraction of the time.

So as you can see, quality drivers are nice but there's much more to designing a speaker than those alone. I'd say 30% driver 20% cabinet construction and 50% crossover. And because I diverged on the crossover, cabinet and drivers then that's a significant proportion to warrant that any comparisons with other designs be made mute and to say its a copy is laughable frankly.

Also I used the Scanspeak tweeters just as I used the Manger, Seas Excel, Scanspeak sliced papers, ATC, Visaton Planars, Volt Radials, B&Cs and the rest because I just wanted to give them a try. I trust very few internet opinions with the exception of a bright chap from the US that I converse with fairly often.

 

I wonder how may mobile salesman get 'trade' in the audio industry that they don't supply the phones too?
Answers on a post card................

 

I'd hazard a guess, maybe one?

 

Shin,

you really do become offensive when people don't grovel at your feet don't you? You sound like a very frustrated man (or woman).

Interesting that you seemed to fit a 9" ATC bass unit the same size cab as that used for their ported alignment but sadly I'm on a mac at the moment so don't have the T&S parameters to hand to look. As for the rest, well I guess I'll just have to take your word for it won't I? After all, there's absolutely no evidence to suggest you didn't simply hook up the DEQX and hit the keyboard is there? Nor any evidence that this speaker you were so desperate to sell on sounded any better than the ATC reference. But of course, lash out and be offensive by all means, it seems to be the one talent you have been able to demonstrate adequately enough to the forum.

Two things do come to mind though. In an earlier post (one of the few where you didn't try to offend other forumites with vulgarity and threatening behavior) you said that the bass units were the same. Now you deny that. Can't you remember or something? Secondly do you have any measurements for the ATC SCM50 cabinet showing any traces of cabinet resonance? Oh and whilst you are at it, 35hz from a small sealed cabinet? you must have employed an enormous amount of EQ to get that figure...

Tony, can I suggest you butt out, politely of course. Your post is as always incorrect and indesipherable, but then maybe it has something to do with the integrity in my profession that appears to be sadly lacking in yours since you started pushing kit with high margin