Newbie questions on a multi-way speaker

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Hi there, first post from someone who has been lurking here for awhile.
I figure almost every new guy ask a silly question, or something that has been asked a thousand times before, so I've been saving my first post for this occasion. :p
The post will be long and 'not to the point', but I appreciate anyone that takes the time. :)

Background:
My current audio system has served me well, the amplifier (NAD 302) is almost 25 years old and the speakers (B&W DM309) 12 years or so, and I listen to music 2-12 hours a day as well as use them for movies. I credit this to a 'held back' sound, I was looking as substantially more expensive speakers but realized I would get tired of long hours of listning to them and would have needed more attention to placement in the room.
But, two things has happened, I've realized I want to run the audio from my TV to the speakers and I upgraded/built new sound system in my car that simply blew my home audio out of the water. Instead of rumbling bass I could hear the strings of the bass guitars of the same songs, and acoustic guitars has some air, and so on.
My questions is regarding multi-way speakers, but I'm looking at the whole system so I don't paint myself in to one corner. Your answer/thoughts can be to just the speaker design or the whole deal.

Positive things:
-I live in a house and have a good 300 meters to my neighbor.
-No wife or girlfriend that will complain. :D
-I'm eager to learn, and got the time to do so.
-I've got space to work in, and the ability to do so.

Negative things:
-Money is very scarce, this will take some time to complete.
-Listning position is pretty bad most of the time, as I use my PC as a media center for music and film and it's positioned on the opposite side of the wall of my TV/Speakers (so I listen to music from opposite room most of the time as I surf).
-That also positions my speakers at one end of the long side of the wall (5.5x3.7 M or 20sqM).

My thoughts so far:
-I need audio input from my TV (optical) and something from my PC (several options with my soundcard).
-I need to be able to control the volume, as the optic signal from my TV isn't level controlled.
-No matter if I use passive or active crossover a mic is a logical purchase.
-Cheapest solution seams to be a miniDSP 2x4HD, as I get the connections and volume control, as well as the ability to fine tune the system all in one package. (Combined with two 2-channel amps that will be DIY)
-I will most likely go with closed enclosure and bump up the low region with the DSP if needed, the new subwoofer in my car made me a believer. (I have modeled a lot of speakers in winisd to see how they behave as well)
-Making a pod for the tweeter (or tweeter and midrange) seems like time well spent to get away a little bit from baffle step, edge diffraction and so on.
-No passive crossover in speaker boxes, that allows me to go full active later, as well as making changes easier.

Questions:
1. My first though was to build a 2.5 speaker using two SEAS H1288-08 CA22RNX, with one of them on a 1:st order filter for the lowest region, and active crossover to something like a SEAS 27TDFC or ScanSpeak D3004/602010 (the ScanSpeak is interesting because of the small size for a pod).
But I'm slightly concerned with how the large CA22RNX will sound in the upper region (guessing crossover at 1800hz or so would be suitable).
2. Second thought is to build a 3-way, using passive crossover between tweeter and midrange, and active to the woofer (2.2 system).
Tweeters would be the same.
Midrange duty either SEAS MCA15RCY, or perhaps CA18RLY.
As a woofer the Wavecor SW270WA01 has looked the best in winisd for my price range.
As the woofer might need to be crossed over at a low(-ish) frequency, the larger CA18RLY maybe is better at extending down a bit compared to the smaller midrange.
3. I'm hoping a well matched set of speakers that has passive crossover could be fine tuned with the DSP and thereby making the passive crossover a more "straight forward" design, as I have understod that a passive filter can get really expensive (both parts and trial&error).
In the 3-way solution I would guess it's smoothing out the the upper region, possibly bringing it down to match the subwoofer in frequency respons.
But maybe I'm making it twice as hard... :confused:

You don't have to do all the legwork for me, I'm just hoping someone can point me in the right direction.
Thank you for your time! :)
 
Maybe it's on the wrong side of the forum, but a small fullranger combined with a subwoofer (a so called "woofer assisted wideband" setup) could be your solution. I use a similar setup with a Mark Audio Alpair 10M gen 3 and a Scanspeak 26W8534G00 sub tuned very low. I crossover low at 180hz (1st order serial passive CR), but you could do it till 5-600Hz with that woofer and let the fullrange do the rest.

The fullrange i use is rather expensive, but there are many cheaper and smaller who can do the same. An Mark Audio Alpair 7 or Pluvia 7 is a lot cheaper and can do it also. And other brands (Tangband, Seas, ...) can do it also with smaller and cheaper drivers.

Like that you can keep it 2 way and use the reasonable priced minidsp 2x4HD as crossover. Analog crossovers will be as expensive to do it right i'm affraid, but you will need an extra amp as you will need 4 channels in a 2 way stereo. With passive you don't need the extra amp, but the trial and error to get the right crossover could cost a lot, especially if you are not an experienced builder...
 
Maybe it's on the wrong side of the forum, but a small fullranger combined with a subwoofer (a so called "woofer assisted wideband" setup) could be your solution. I use a similar setup with a Mark Audio Alpair 10M gen 3 and a Scanspeak 26W8534G00 sub tuned very low. I crossover low at 180hz (1st order serial passive CR), but you could do it till 5-600Hz with that woofer and let the fullrange do the rest.

The fullrange i use is rather expensive, but there are many cheaper and smaller who can do the same. An Mark Audio Alpair 7 or Pluvia 7 is a lot cheaper and can do it also. And other brands (Tangband, Seas, ...) can do it also with smaller and cheaper drivers.

Like that you can keep it 2 way and use the reasonable priced minidsp 2x4HD as crossover. Analog crossovers will be as expensive to do it right i'm affraid, but you will need an extra amp as you will need 4 channels in a 2 way stereo. With passive you don't need the extra amp, but the trial and error to get the right crossover could cost a lot, especially if you are not an experienced builder...

Thank you, that driver do look interesting, and as I'm +40 the upper frequencies isn't something I worry too much about so maybe a fullrange would do the trick.

I have read a lot about crossovers (on this forum as well as other places), watched videos etc, but I have yet to start to do any tests in software.
But my idea (right or wrong) was to pick some "classic" well behaved drivers (as opposed to modern magnesium coned etc) that many others have experience with. Build the boxes, use the mic to get actual measurements in those boxes (to eliminate estimation on baffle step, edge diffraction etc), then use software and possibly a couple of pointers from someone to build say a basic 2 order crossover.
Then use the DSP to iron out anything that's protruding too much.

I guess one thing I could do is get the DSP and resonable woofers to what I've got now and take it from there.
But... I've got a CAD software that is about to expire, so getting in front and doing the design work for new speakers do make sense. I'm just afraid I might make some rookie mistake (yes, I've read enough to be humble :p ).
 
Ok, I read over your post (admittedly a bit quickly) and there are a couple of suggestions that come to mind.

First, move the computer into your listening room, hook it up to the big screen and use a wireless keyboard to control it. If that's not practical, you can look into setting up an htpc or one of those android boxes in your listening room, network it with the main computer, and again use a wireless keyboard. Modern PCs don't have to be big or loud... I'm attaching a photo of one I build for friends and friends of friends, that is practically silent and runs Windows no problem.

This simple 2 computer home networking solution works really well.

A second note from your description is that you aren't really setting your system up for the best sound. There are a ton of websites out there with detailed descriptions of the best system and speaker placement. A very basic image is attached.

I'm thinking that what you may discover by getting your speakers centered on a wall, adjusting your seating position and improving the way you feed your system just might let you solve the rest of the problems more inexpensively.
 

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Ok, I read over your post (admittedly a bit quickly) and there are a couple of suggestions that come to mind.

First, move the computer into your listening room, hook it up to the big screen and use a wireless keyboard to control it. If that's not practical, you can look into setting up an htpc or one of those android boxes in your listening room, network it with the main computer, and again use a wireless keyboard. Modern PCs don't have to be big or loud... I'm attaching a photo of one I build for friends and friends of friends, that is practically silent and runs Windows no problem.

This simple 2 computer home networking solution works really well.

A second note from your description is that you aren't really setting your system up for the best sound. There are a ton of websites out there with detailed descriptions of the best system and speaker placement. A very basic image is attached.

I'm thinking that what you may discover by getting your speakers centered on a wall, adjusting your seating position and improving the way you feed your system just might let you solve the rest of the problems more inexpensively.

I actually have a wireless keyboard, usb-hub etc in my living room, so I could sit in my couch all the time.
But, the sound is actually a bit more annoying as it gets more directional and the bass is somewhat erratic as well.
Due to windows, door and furniture it would be a massive undertaking to rearrange the room actually, but the thought has crossed my mind as well.

I have done DIY builds in younger age, and I'm not... totally lost(?), even it might seem like it. :p

The distance to listening position (couch) might lend itself better to small speakers on stands or possibly even on-wall speakers, but I have a hard time with 2.1 systems as the bass tend to be noticeably coming from another place.
Otherwise I do have a great subwoofer over from my car, so I could build a box for it and possibly even get another one.

Maybe I need to start thinking outside the box (no pun intended) and stop thinking that great speakers needs to be big and be standing on the floor... :)
 
I actually have a wireless keyboard, usb-hub etc in my living room, so I could sit in my couch all the time.
But, the sound is actually a bit more annoying as it gets more directional and the bass is somewhat erratic as well.
Due to windows, door and furniture it would be a massive undertaking to rearrange the room actually, but the thought has crossed my mind as well.

The reason I suggested this is that your room might well be part of your problem. I've seen a bad room totally mess up some very expensive speakers.

I have done DIY builds in younger age, and I'm not... totally lost(?), even it might seem like it. :p

No worries ... I used to be a DIYer before I turned it into a profession. Now I'm back at it and still getting a feel for the current trends...

The distance to listening position (couch) might lend itself better to small speakers on stands or possibly even on-wall speakers, but I have a hard time with 2.1 systems as the bass tend to be noticeably coming from another place.

Not necessarily. It's about positioning... I have a cabinet maker I deal with and he builds stereo stands that have the sub built into the bottom. Put it between your speakers and you're off and running.

Maybe I need to start thinking outside the box (no pun intended) and stop thinking that great speakers needs to be big and be standing on the floor... :)

That's about room size more than anything else.

My listening area is about 12 by 14. A photo of my system is attached... Note that it's on a short wall with a hallway on one side and my dining room (home office) on the other. I sit opposite in the sweet spot. No subwoofer. The sound is just right for me.

I think the whole "my speakers could be better" issue is often more a matter of "my room could be better" than anything, although there are definitely some bad speakers out there.
 

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The reason I suggested this is that your room might well be part of your problem. I've seen a bad room totally mess up some very expensive speakers.

No worries ... I used to be a DIYer before I turned it into a profession. Now I'm back at it and still getting a feel for the current trends...

Not necessarily. It's about positioning... I have a cabinet maker I deal with and he builds stereo stands that have the sub built into the bottom. Put it between your speakers and you're off and running.

That's about room size more than anything else.

My listening area is about 12 by 14. A photo of my system is attached... Note that it's on a short wall with a hallway on one side and my dining room (home office) on the other. I sit opposite in the sweet spot. No subwoofer. The sound is just right for me.

I think the whole "my speakers could be better" issue is often more a matter of "my room could be better" than anything, although there are definitely some bad speakers out there.

I did have it arrangerad 'right' before with the speakers on one short side of the room, but I really can't recall it made a big difference, but then again it was +10 years ago before I got a TV and my memory might fail me. :)

I have tried various positions where they stand now, but as I recall it mostly made a difference in the low end.
And no matter where I stand in the room there isn't that much difference (within reason), apart from the bass that is best against the wall where my couch is (if I tilt my head back).

The reason why I've been able to live with them for so long and been able to listen so much is probably due to their lack of "brightness" and "clarity". My taste in music goes from old Blues to classic Rock, Hard Rock on to some Metall, and I also have a 'thing' for Live recordings. Anything up to about mid 70's is working fine, but more modern recordings or film they fall behind.

I'm not sure, but looking at the frequency range/respons: -6dB 40-42kHz, +/-3dB 60-22kHz, I'm guessing that the vents are tuned fairly high and they don't offer the same transient respons.

Now I do know that in my car I need to be aware of cabin gain etc but a single 8" in closed box was Really impressive compared to my B&W speakers, not in dB as I had it turned down, but attack and transient respons made some 'old' music sound like new (Noticed on Joe Bonamassa "Driving Towards The Daylight").
(On a side note, I replaced that 8" with a 10" of the same make and modell and lost some transient respons, but did gain some pressure)

So... I did think about using two of those subwoofers positioned beneath in a box, like you suggest. That lead me down the route of the 3-way speaker I listed, as that Wavecor 10" looks really nice in a closed box and would perhaps compensate for the difference in cabin gain, and at low listing levels on film I could bump up the low end in the DSP. (Not really fond on the idea of a logotype on the speaker as well)

I agree completely in the "it's right for me", speakers is like food, we all have different taste. :) And I don't want to end up with over seasoned takeout food. :p
 
Without any evidence I'm inclined to consider the response you get in your room and what can be done about it. Transient response is connected to this.

I read through the paper now and it was interesting! :)
I believe I should try some acoustic damping on the walls no matter what route I take on the speakers. I have a Oak floor and a Pine ceiling, so I will look in to that too.




In regards of speakers, I'm not against building something that's been tried before, I have no need to reinvent the wheel.
Would Seas Mimir work as a ground, making the cabinet closed instead, and adding a larger subwoofer for the low frequencies?
MIMIR
 
I did have it arrangerad 'right' before with the speakers on one short side of the room, but I really can't recall it made a big difference, but then again it was +10 years ago before I got a TV and my memory might fail me. :)

Long side/short side doesn't really matter. It's the relationship between your listening position and the speakers that make the biggest difference. The "stereo image" really only works in one spot. When it's right, you really have no impression of listening to speakers, the sound plays out across the room in front of you and the speakers seem to disappear (acoustically). On movies, the sound plays out on the screen, again giving you no direct sense of listening to speakers.

I have tried various positions where they stand now, but as I recall it mostly made a difference in the low end.
And no matter where I stand in the room there isn't that much difference (within reason), apart from the bass that is best against the wall where my couch is (if I tilt my head back).

Actually, in that position, it's probably more accurate to say "the bass reflection that is best..." That's what is called Wall Gain and while not entirely a bad thing, it can seriously muddy the sound.

The reason why I've been able to live with them for so long and been able to listen so much is probably due to their lack of "brightness" and "clarity". My taste in music goes from old Blues to classic Rock, Hard Rock on to some Metall, and I also have a 'thing' for Live recordings. Anything up to about mid 70's is working fine, but more modern recordings or film they fall behind.

Yes... late 1960s up to early 1990s for me. Anything after that is merely evidence of increasingly poor sound mixes and the runaway use of compression. It actually gives me headaches.

I'm not sure, but looking at the frequency range/respons: -6dB 40-42kHz, +/-3dB 60-22kHz, I'm guessing that the vents are tuned fairly high and they don't offer the same transient respons.

Damn... that's good response.

It could be porting ... here's a trick you can try... literally stuff a sock in it... block the port with some soft wool socks or fluffy fabric and see what happens. Another trick, that I use, is to make a small tube of soft material (foam rubber works great) the size of the ports and about 1/8 inch thick then slide those into the ports and see what you get... Most often it will slightly detune the port and bring out a much more structured bass.

But it could also be the room ... carpeting, even a throw rug in front of the speakers can make a huge difference. Soft artwork on the walls is a big help too.

But don't get carried away, there's no reason to build an anechoic chamber, you wouldn't like that either.

So... I did think about using two of those subwoofers positioned beneath in a box, like you suggest. That lead me down the route of the 3-way speaker I listed, as that Wavecor 10" looks really nice in a closed box and would perhaps compensate for the difference in cabin gain, and at low listing levels on film I could bump up the low end in the DSP. (Not really fond on the idea of a logotype on the speaker as well)

I always suggest that you never eliminate any possibility until you've tried all the reasonable ones...

I agree completely in the "it's right for me", speakers is like food, we all have different taste. :) And I don't want to end up with over seasoned takeout food. :p

Yep... I get plenty of bass with no subwoofers, voices are very natural sounding, and music is just amazing ... I see no reason to tamper with that!
 
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Long side/short side doesn't really matter. It's the relationship between your listening position and the speakers that make the biggest difference. The "stereo image" really only works in one spot. When it's right, you really have no impression of listening to speakers, the sound plays out across the room in front of you and the speakers seem to disappear (acoustically). On movies, the sound plays out on the screen, again giving you no direct sense of listening to speakers.


Actually, in that position, it's probably more accurate to say "the bass reflection that is best..." That's what is called Wall Gain and while not entirely a bad thing, it can seriously muddy the sound.



Damn... that's good response.

It could be porting ... here's a trick you can try... literally stuff a sock in it... block the port with some soft wool socks or fluffy fabric and see what happens. Another trick, that I use, is to make a small tube of soft material (foam rubber works great) the size of the ports and about 1/8 inch thick then slide those into the ports and see what you get... Most often it will slightly detune the port and bring out a much more structured bass.

But it could also be the room ... carpeting, even a throw rug in front of the speakers can make a huge difference. Soft artwork on the walls is a big help too.

But don't get carried away, there's no reason to build an anechoic chamber, you wouldn't like that either.


I always suggest that you never eliminate any possibility until you've tried all the reasonable ones...


Yep... I get plenty of bass with no subwoofers, voices are very natural sounding, and music is just amazing ... I see no reason to tamper with that!

I do get a sound stage, though at a very narrow point, but that might due to the distance as you say. (And yes, I have moved around my speakers)

Against the wall the bass has a fuller sound to it, but it's still not any details in the sound, it's a tone and not an instrument that you hear (even listening near field).
These didn't sound that great in the shop when I compared them next to others on the same amplifier, but I felt it was right for me, and now I want more. :)
They are really cheaply built, I found some old post on this forum about it.

Maybe I have a problem with my old amplifier as well, I got my Genesis amplifier in the car upgraded and fine tuned and that made a huge difference.

I will look in to getting something on the wall, some frames with acoustic damping material in them and wrapped in some suitable fabric. :)




But as a back-up plan, the Seas Mimir looks kind of interesting, though I would prefer closed enclosure. The driver CA18RNX has a bit too low Qts, but the CA18RLY seems good at 0.47 and the higher Fs wouldn't do much if I use them with subwoofers.
The sensitivity is also matched better to the tweeter 27TDFC, so my thought was that it might be possible to tweak the filter slightly for my application and gain some over all sensitivity.
But, I'm really green when it comes to that, I need some time on simulating things to get an idea of what to do.

I believe I've read several posts about them on this forum, though I can't seem to find them right now...
 
I do get a sound stage, though at a very narrow point, but that might due to the distance as you say. (And yes, I have moved around my speakers)
The perfect sweet spot isn't going to be very big... maybe 2 feet or so wide. You can toy with that by rotating the speakers in place... I don't like speakers pointed directly at me, a bit further out usually brings a more palatable result.

Against the wall the bass has a fuller sound to it, but it's still not any details in the sound, it's a tone and not an instrument that you hear (even listening near field).
These didn't sound that great in the shop when I compared them next to others on the same amplifier, but I felt it was right for me, and now I want more. :)
They are really cheaply built, I found some old post on this forum about it.

They are also a 2.5 way design and that can bring a whole mess of phase issues with it.

Maybe I have a problem with my old amplifier as well, I got my Genesis amplifier in the car upgraded and fine tuned and that made a huge difference.

It's possible, but I've always found that 90% of the difference comes from the speakers and room, not the electronics.


I will look in to getting something on the wall, some frames with acoustic damping material in them and wrapped in some suitable fabric. :)

I often use Canvas wall art like THIS I find that the freely hanging canvas works as well as many accoustic panels, and looks a lot better.

FWIW... you won't be the first person to regret buying B&W speakers.

My point was to make sure it's the speakers and not the room before you make another purchase you regret.
 

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Against the wall the bass has a fuller sound to it, but it's still not any details in the sound, it's a tone and not an instrument that you hear
A speaker can work perfectly with a wall but has to be designed for it. If not, then a wall can be a problem.
a 2.5 way design and that can bring a whole mess of phase issues with it.
How do you figure?
 
A speaker can work perfectly with a wall but has to be designed for it. If not, then a wall can be a problem.

I believe his are rear ported, just above the connectors... so putting it against the wall will cause frequency response problems by blocking the port.

Generally the closest you can get to a wall without sonic impact will be the depth of the port tube away. (Not a known rule, just experience talking)


2.5 way crossovers can introduce phase variations depending upon how they are implemented. If not done as two separate low pass filters they can be off by quite a bit.
 
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I guess I was thinking more in general, and the upper low frequencies are common complaints when going close to walls. I wanted to warn that under some circumstances walls tend to be more of a do or don't proposition, despite the notion that there are always varying degrees of wall assistance. It's a bit like BSC in that way.
2.5 way crossovers can introduce phase variations depending upon how they are implemented. If not done as two separate low pass filters they can be off by quite a bit.
Anything that isn't done right could be a mess, I guess?
 
Thank you for the pointers, I like the idea a canvas wall art as well.

These are rear vented, two ports, and is standing a 1ft from the wall right now.
Not going by any acoustic impacts, 25% of the diameter of the port is the bare minimum for flow restrictions, but even at that there will be big restrictions.

I will try a rug I've got and see what I can do with it, as well as covering the ports.
Moving walls isn't my first hand choice, I've got a log house. :p

As to the Room Eq Workshop, I didn't find any specific software, is there any that you can recommend?
(I have downloaded a bunch of different software's for crossover, boxes, etc. But wanted to get going with sorting out a handfull of drivers first)
 
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