Rebuild Advent Heritage-new drivers/xover-need help - AVS Forum
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post #1 of 48 Old 12-29-2009, 10:38 AM - Thread Starter
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Hello,

Here's where I'm at:
NAD and PSB 500i's on stands upstairs for music only. The sound excellent.
HT with Advent Heritage floorstanders downstairs. They sound great with HT, but are lacking for music. not very transparent, and vocals/mids seem a bit weak or "cheap". Beautiful hardwod cabs.

I've been planning on building a pair of floorstanders, about $400-$750 for drivers and hardware(I'd like to keep it as low as possibkle, but with great sound). I can supply wood and have a woodshop/skillz. I've been eyeing the GR Research N3 towers for an idea.

I've had the idea to move the PSB's down the the HT, as I'm adding a sub.

Also had the idea to rebuild the Advent instead of building from scratch as the cabs are really nice and match everything upstairs wonderfully. I can beef up the front baffle, add bracing or compartments, etc. The tweeter is actually pretty good, but I'm not opposed to switching it out or trying a ribbon like the N3 has.

Each tower has two woofers (I guess a mid and low), both are about 8" to 8.125" in diameter which I've found is a strange size. I can put a slightly smaller driver or route the flange opening slightly larger if I have to, but it may be a bit tricky. Not too worried about that. If I went this route, a new xover is in order I'm sure but this gets way out of my skillz range.

So what do you think? Anyone have any ideas for drivers and xovers?

The cabs are 37.75"h x 10.5"w x 13"d
-one tweet, 2-8" drivers each.
-driven by NAD 312/Adcom GFA-535 (about 80wpc)
-no sub

Here's the current Advent xover:
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post #2 of 48 Old 12-29-2009, 12:49 PM
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The major limiting factor will be the 10.5" width of your cabinets, it's a measurement important for duplicating the response of any existing designs that you may want to replicate. To match box volume, you can just segment your cabinets smaller as needed.

With the 10.5" width locked in, look through the various 8" 2, 2.5, and 3-way designs that are published for the best odds on finding ones that come as close as possible to your width and are smaller or equal to your box volume.

Other than that, it shouldn't be too hard to cut out your existing baffle and set up your cabinets with rabbits to accept the new baffles that you will have to make for your new drivers.
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post #3 of 48 Old 12-30-2009, 07:47 AM - Thread Starter
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[quote=NJTEX;17808750]The major limiting factor will be the 10.5" width of your cabinets, it's a measurement important for duplicating the response of any existing designs that you may want to replicate. To match box volume, you can just segment your cabinets smaller as needed.
QUOTE]

Are you saying this is too wide? So I might have to put in a false wall to make the inside space smaller?

The ways these are built, there is a solid hardwood top and front baffle. The sides, back and skirt around tghe bottom are just covered in black melamine or similar. I guess there's no way to make the enclosure narrower and 'save' the hardwood unless I did it on the interior. Most drivers seemed to be in the 8.5 to 8.75 range, so I'd probably be rabbiting with a bearing bit to make the flange cut wider.

Any bracing would have to go in through a driver hole, but I guess that's not too difficult. Doing large panels to make an interior side wall is another story. I'd have to slice off the whole back or the bottom or something. Any ideas on that?? A major benefit of inserting false sidewalls would be the chance to do sand filled for uber dampening. I've heard of people doing this on subs, but would it have benefit for regular towers? I would guess with 8" it might.
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post #4 of 48 Old 12-30-2009, 03:02 PM
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Here's an idea that looks interesting, dual 8" with ribbon tweeter. Maybe someone can kick in ideas for drivers and crossover design.

http://www.slsloudspeakers.com/content/view/194/103/
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post #5 of 48 Old 12-31-2009, 02:00 PM
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Quote:
Originally Posted by Lightspeed66 View Post

Hello,

Here's where I'm at:
NAD and PSB 500i's on stands upstairs for music only. The sound excellent.
HT with Advent Heritage floorstanders downstairs. They sound great with HT, but are lacking for music. not very transparent, and vocals/mids seem a bit weak or "cheap". Beautiful hardwod cabs.

I've been planning on building a pair of floorstanders, about $400-$750 for drivers and hardware(I'd like to keep it as low as possibkle, but with great sound). I can supply wood and have a woodshop/skillz. I've been eyeing the GR Research N3 towers for an idea.

I've had the idea to move the PSB's down the the HT, as I'm adding a sub.

Also had the idea to rebuild the Advent instead of building from scratch as the cabs are really nice and match everything upstairs wonderfully. I can beef up the front baffle, add bracing or compartments, etc. The tweeter is actually pretty good, but I'm not opposed to switching it out or trying a ribbon like the N3 has.

Each tower has two woofers (I guess a mid and low), both are about 8" to 8.125" in diameter which I've found is a strange size. I can put a slightly smaller driver or route the flange opening slightly larger if I have to, but it may be a bit tricky. Not too worried about that. If I went this route, a new xover is in order I'm sure but this gets way out of my skillz range.

So what do you think? Anyone have any ideas for drivers and xovers?

The cabs are 37.75"h x 10.5"w x 13"d
-one tweet, 2-8" drivers each.
-driven by NAD 312/Adcom GFA-535 (about 80wpc)
-no sub


Are the speakers going to be placed close to the wall? A 2.5 design generally has a lot of baffle step, and might tend to sound overly warm when placed near a wall. Do you need the speaker to be 8 ohm, or is the amp capable of driving a 4 ohm load?

Here's a woofer you might want to check out.
http://www.madisound.com/catalog/pro...roducts_id=834

Here's a mid if you want a 3-way.
http://www.madisound.com/catalog/pro...oducts_id=1597

And why not a SEAS tweeter as well?
http://www.madisound.com/catalog/pro...oducts_id=8322
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post #6 of 48 Old 01-01-2010, 07:39 AM - Thread Starter
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Quote:
Originally Posted by kbgl View Post

Are the speakers going to be placed close to the wall? A 2.5 design generally has a lot of baffle step, and might tend to sound overly warm when placed near a wall. Do you need the speaker to be 8 ohm, or is the amp capable of driving a 4 ohm load?

Here's a woofer you might want to check out.
http://www.madisound.com/catalog/pro...roducts_id=834

Here's a mid if you want a 3-way.
http://www.madisound.com/catalog/pro...oducts_id=1597

And why not a SEAS tweeter as well?
http://www.madisound.com/catalog/pro...oducts_id=8322

I had looked at those drivers before. It would be a 2.5 using the current baffle which what I'd do. Not sure what the amp drives, but Adcom says its a high current amp?

Right now they are placed about 1 foot from the back wall, with about 1.5 on one side and 6 or more on the other.

Question, excuse my ignorance. On a 2.5 way system, does the middle driver get a bandpass and handle mids or is it doing the same thing as the lower woofer?
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post #7 of 48 Old 01-01-2010, 08:22 AM
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Quote:
Originally Posted by Lightspeed66 View Post

I had looked at those drivers before. It would be a 2.5 using the current baffle which what I'd do. Not sure what the amp drives, but Adcom says its a high current amp?

Right now they are placed about 1 foot from the back wall, with about 1.5 on one side and 6 or more on the other.

Question, excuse my ignorance. On a 2.5 way system, does the middle driver get a bandpass and handle mids or is it doing the same thing as the lower woofer?

The upper woofer runs up to the tweeter crossover point and the lower woofer typically runs up to around 1k Hz. This configuration provides baffle step correction with the bottom woofer and allows for the desired center to center spacing with the tweeter for the top woofer.
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post #8 of 48 Old 01-01-2010, 08:27 AM
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Quote:
Originally Posted by Lightspeed66 View Post

I had looked at those drivers before. It would be a 2.5 using the current baffle which what I'd do. Not sure what the amp drives, but Adcom says its a high current amp?

Right now they are placed about 1 foot from the back wall, with about 1.5 on one side and 6 or more on the other.

Question, excuse my ignorance. On a 2.5 way system, does the middle driver get a bandpass and handle mids or is it doing the same thing as the lower woofer?

Both driver handle the lowest bass. At about 400 hz or so, the bottom woofers output starts getting reduced. By 3k or so it is way down and doesn't interact with the tweeter. So the middle woofer operates like a 2-way. The lower woofer adds 6dB of low bass, but only adds 2 or 3 dB at 600 or so, and by 1k is not adding anything. (These are ballpark numbers.)

Check post #118 of this thread, and the last page, and you can see some simulations, and measurements.
http://www.avsforum.com/avs-vb/showt...ight=lennon_68
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post #9 of 48 Old 01-01-2010, 05:29 PM - Thread Starter
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The more I look at those drivers, they look like they may be the best offerings for the situation at Madisound. My box size looks like it's about 2.1cu ft. per, and I figure if I add a thicker baffle and bracing, etc it might go down to 1.8 or so.

My questions at this stage would be: could it remain a sealed enclosure, or would it benefit from adding a port? Also, since electronics is not my forte and I don't have the test equipment, what would be the best way for me to get to a solid crossover design for this enclosure and those drivers?

Once I had a xover and it was built, how much tweaking would a crossover typically need? Is it usually based on audible feedback, or electronic frequency measurements? I'm guessing both. I guess I'm wondering how close I could get if someone else knew the box design and size, the drivers specs, etc?
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post #10 of 48 Old 01-01-2010, 08:16 PM
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Lightspeed66, like you, I like those seas drivers. I have been thinking of selling my speakers and doing a 5.0 DIY speaker set-up using those drivers, for the price, they got my attention. My front speakers would be sealed towers using the seas tweter, mid and woofer. I've done a couple of DIY subwoofers (one sealed and one with PR's) so I'm o.k. with the woodworking part but the electronic part of these speakers (crossovers) is what has me a little bit worried since I have no experience with that.

Looking at Parts Express, I see that they carry several Dayton 2 and 3 way crossovers, would they work for these speakers? What would the best crossover points be for each of these drivers? If using a sub with a 80hz crossover, would these work well in a sealed enclosure? Also, it looks like to power all these drivers to their full potential you would need a separate amp with 200-300w per channel (my receiver only does 120w per channel at 8ohms), is that the case? Finally, for the center/surrounds speakers, the same tweter can be used as the fronts but the mid might be too small and the woofer too big for them, right? so maybe using another size seas driver, like a 6" or 7" might be a better option? Thanks.
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post #11 of 48 Old 01-01-2010, 08:58 PM
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There's a couple guys around who can design you a x-over using software and the posted measurements. I have no software, but know about what is needed. (I have a WAG.) A premade x-over could work OK with the right drivers, or with some alterations. The tweeter will need someting more custom than a premade x-over. Maybe a different tweeter should be used if you want to use a premade x-over. There was a Cygnet kit mentioned on the woofer data sheet, but I couldn't get the link to work. Anyone know what it is?

There's no need for porting if using from 80 hz up.

These speakers would work fine with a 100w amp. They could potentially handle more power, and survive some abuse that other drivers might not.

I'd probably cross at 600 hz and 3k, although those drivers should allow for a lot of options, including a 2-way.
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post #12 of 48 Old 01-01-2010, 09:23 PM
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kbgl, thanks for that response. Maybe I can have someone build the crossovers? I wonder how much they would be for a 5.0 set-up.
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post #13 of 48 Old 01-01-2010, 09:36 PM
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Quote:
Originally Posted by spanish68 View Post

kbgl, thanks for that response. Maybe I can have someone build the crossovers? I wonder how much they would be for a 5.0 set-up.


Check with Rick.
http://www.selahaudio.com/
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post #14 of 48 Old 01-01-2010, 09:47 PM
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Quote:
Originally Posted by Lightspeed66 View Post

The more I look at those drivers, they look like they may be the best offerings for the situation at Madisound. My box size looks like it's about 2.1cu ft. per, and I figure if I add a thicker baffle and bracing, etc it might go down to 1.8 or so.

My questions at this stage would be: could it remain a sealed enclosure, or would it benefit from adding a port? Also, since electronics is not my forte and I don't have the test equipment, what would be the best way for me to get to a solid crossover design for this enclosure and those drivers?

Once I had a xover and it was built, how much tweaking would a crossover typically need? Is it usually based on audible feedback, or electronic frequency measurements? I'm guessing both. I guess I'm wondering how close I could get if someone else knew the box design and size, the drivers specs, etc?

If you go with sealed, you only need .5 cu-ft per woofer. You can add solid filler to reduce the box volume if needed. If my calculation is correct, you wouldn't really need to make it smaller.
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post #15 of 48 Old 01-02-2010, 07:48 AM - Thread Starter
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If you go with sealed, you only need .5 cu-ft per woofer. You can add solid filler to reduce the box volume if needed. If my calculation is correct, you wouldn't really need to make it smaller.

I figured it would be a bit smaller because of adding a back plate to the front baffle to make it double thick, plus some bracing.

My main goals are sound quality and the ability to run WITHOUT a sub. These would be my upstairs, music only speakers without sub. So, I'm looking for as flat and low of output as possible, fast and clean. I know I can only expect so much out of this, but I'd like to optimize it as much as I can.

Choosing these drivers (the two 8" and tweeter for each box) with the goal of sound quality and full low with no sub, my main questions are:

-port or no port
-sealed chambers for each driver, some, or just bracing?
-best crossover design

I could build a crossover if someone told me what parts and drew more of a map rather than a schematic. I'm sure he prebuilt from PartsExpress are probably not going to cut it for this application.
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post #16 of 48 Old 01-02-2010, 08:19 AM
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Quote:
Originally Posted by Lightspeed66 View Post

I figured it would be a bit smaller because of adding a back plate to the front baffle to make it double thick, plus some bracing.

My main goals are sound quality and the ability to run WITHOUT a sub. These would be my upstairs, music only speakers without sub. So, I'm looking for as flat and low of output as possible, fast and clean. I know I can only expect so much out of this, but I'd like to optimize it as much as I can.

Choosing these drivers (the two 8" and tweeter for each box) with the goal of sound quality and full low with no sub, my main questions are:

-port or no port
-sealed chambers for each driver, some, or just bracing?
-best crossover design

I could build a crossover if someone told me what parts and drew more of a map rather than a schematic. I'm sure he prebuilt from PartsExpress are probably not going to cut it for this application.


Look at the woofer spec page near the bottom. They show that in 1 cu-ft ported, the f3 is 43 hz. That is a lot better than the sealed f3 of 65 hz. It's no contest. You will want to port it. But your box may be a little small at 1.8 cu-ft. You will be closer to the .75 cu-ft f3 of 48 hz.

Do you move the speakers out from the wall for "audiophile" type listening?

If you modify the box to use just a single woofer, these would be on my list. Both go much deeper. The Peerless would be easier to make a 2-way. The SEAS maybe would be better in a 3 way.
http://www.madisound.com/catalog/pro...oducts_id=1704

http://www.madisound.com/catalog/pro...oducts_id=1605
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Lightspeed66, I'm going to ask kbgl a few more final questions and leave your thread alone, I've done enough interference already.

kbgl, for the surrounds and center channel speakers (all will be using the same tweter), would you use mids or woofers? What size? I want the surrounds to be on the small side, the center, I can make any size I want. Are the Seas 4.5" mids too small? Madisound also has them in 5.5", which might be better. I could make the center channel a two mids or two woofers design.

If I come up with 0.75cf sealed for the woofer and change the F3 from 65hz (at 0.5cf) to a lower F3 number, it should not be a problem, right? Finally, will these speakers hold their own vs commercial speakers in the $1,500-$2,500 range? For the price/performance ratio, I like the Energy RC70 at around $1,500, but these Seas speakers should be better (if done right), no? Thanks again.
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post #18 of 48 Old 01-02-2010, 11:30 AM
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spanish68 send me a very short PM. I typed one to you but can't send it unless it is a reply. Something strange with the software.
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post #19 of 48 Old 01-02-2010, 04:40 PM
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kbgl, I hope you got my message, hopefully it got fixed.
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post #20 of 48 Old 01-02-2010, 06:59 PM
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Yes, I got it, and sent a long winded reply.
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post #21 of 48 Old 01-03-2010, 08:00 AM - Thread Starter
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Quote:
Originally Posted by kbgl View Post

Look at the woofer spec page near the bottom. They show that in 1 cu-ft ported, the f3 is 43 hz. That is a lot better than the sealed f3 of 65 hz. It's no contest. You will want to port it. But your box may be a little small at 1.8 cu-ft. You will be closer to the .75 cu-ft f3 of 48 hz.

Do you move the speakers out from the wall for "audiophile" type listening?

If you modify the box to use just a single woofer, these would be on my list. Both go much deeper. The Peerless would be easier to make a 2-way. The SEAS maybe would be better in a 3 way.
http://www.madisound.com/catalog/pro...oducts_id=1704

http://www.madisound.com/catalog/pro...oducts_id=1605

I'm slightly confused on the cu-ft recommendations. If they recommend 1 cu-ft for a certain frequency, does this mean that the woofer would be partitioned off? If you had two woofers, would that mean each woofer would be partitioned off or would you use a combined total?
Since the top woofer is hitting mid frequencies also, is its encloser size the same or different?
Where would the port be? It wouldn't make sense to port unless both of the woofer chambers were connected by airspace would it?

I think I could beef up the front baffle and brace with minimal interference, maybe keep it around 2 cu-ft. The front baffle loks like solid hardwood, and is why I'd probably not make it a 2-way (although it seem like it would be the way to go). It would be very difficult to match the grain and make it look 'right' unless I did something wierd like putting the port where the bottom woofer was (with a huge 8' diameter flare/flange).

Hmm .. now that I think of it, I could make a new baffle and paint it black, but only have it come down the the bottom woofer hole. I've seen plenty of designs like this and they look nice. I'd prefer to keep the original cabinet intact.

I don't ever pull the speakers out from the wall just for a listening session. These are in the main living area and more for ambient listening, although I do sit and critical listen and I'm pretty picky about my sound (which is why I wanted to do this anyways). Seems like the port may want to be on the back side so I could get some loading from the wall and/or ability to adjust that somewhat.

Side note: I'm still intrigued by ribbon tweeters. Would these match up well with the SEAS P21RF?
http://www.madisound.com/catalog/pro...oducts_id=8290



I really appreciate your help.
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post #22 of 48 Old 01-03-2010, 08:22 AM
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Quote:
Originally Posted by Lightspeed66 View Post

I'm slightly confused on the cu-ft recommendations. If they recommend 1 cu-ft for a certain frequency, does this mean that the woofer would be partitioned off? If you had two woofers, would that mean each woofer would be partitioned off or would you use a combined total?
Since the top woofer is hitting mid frequencies also, is its encloser size the same or different?
Where would the port be? It wouldn't make sense to port unless both of the woofer chambers were connected by airspace would it?

I think I could beef up the front baffle and brace with minimal interference, maybe keep it around 2 cu-ft. The front baffle loks like solid hardwood, and is why I'd probably not make it a 2-way (although it seem like it would be the way to go). It would be very difficult to match the grain and make it look 'right' unless I did something wierd like putting the port where the bottom woofer was (with a huge 8' diameter flare/flange).

Hmm .. now that I think of it, I could make a new baffle and paint it black, but only have it come down the the bottom woofer hole. I've seen plenty of designs like this and they look nice. I'd prefer to keep the original cabinet intact.

I don't ever pull the speakers out from the wall just for a listening session. These are in the main living area and more for ambient listening, although I do sit and critical listen and I'm pretty picky about my sound (which is why I wanted to do this anyways). Seems like the port may want to be on the back side so I could get some loading from the wall and/or ability to adjust that somewhat.

I really appreciate your help.

The bigger the box, the deeper it will go. The f3 figures they mention are for one woofer in a 1 cu-ft box. With 2 woofers, you need 2 cu-ft to achieve the same f3. Your box will house 2 woofers, giving a little more than .75 cu-ft for each woofer, so your f3 will be higher like they show for a .75 box.

Dividing the box between woofers can be done, and might be a little better, but it would be more work, and you will need two ports. Ports get in the way inside the box making it awkward sometimes to get a big x-over board inside.
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post #23 of 48 Old 01-03-2010, 08:37 AM - Thread Starter
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Excellent. Well, I think what I'll do is aim for two SEAS P21RF (unless I want to go 2-way at the last second). I'll keep the box open inside except for some well placed bracing which I'll insert in 2-pieces at a time through the woofer holes. I'm not sure if I'll be able to make the baffle double thickness by inserting only through the woofer holes or if thats worthwhile.
I'll pair the woofers with either the SEAS 27TBCD or the LCY-108, the latter would actually be easier to use as I can build a new flange for it that would fit the current flange recess.

2" flared port, around 6" long, placed in the back maybe 1/3 way up from the bottom? Is there an ideal place or is it somewhat arbitrary?

Then a new xover design, and a beer for kbgl. :-)
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post #24 of 48 Old 01-03-2010, 11:01 AM
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To repeat my previous warning. A 2.5 will tend to sound bass heavy when placed near a wall.

A really cool option would be to divide the box by making a .5 cu-ft chamber for the top woofer. Make it your midrange. Then the remaining portion of the box is a little over 1 cu-ft and with one woofer using it, you can get a little more bass extension. A 3-way will also give you more flexibility in voicing the speaker.

Can you post a picture of the box? What size are the driver holes?
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post #25 of 48 Old 01-03-2010, 11:08 AM - Thread Starter
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Ya I'll post pics, plus measurements of hole locations in a bit. I've got to finish my wifes recessed lighting first or im dead. lol
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post #26 of 48 Old 01-04-2010, 07:34 AM - Thread Starter
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OK, here's the speakers as they are now.



The distance from the center of the tweeter to the center of the midwoofer is 7".
The distance from the midwoofer to the bottom woofer is 9".
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post #27 of 48 Old 01-04-2010, 04:35 PM
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That's a really nice cabinet!

I assume that it is a 2.5 design from what I see, but thought you said somewhere that it was a 3-way. Have you considered taking a shot at improving the x-over. Sometimes a small change can make a difference. Can you make out part values and layout of the x-over?

How loud do you want to play music? Do you want to go over about 90dB?

Can we get a closeup of the woofer where it is recessed into the box? Do you want to have the grills off on occasion? I would. If you do, I think both drivers should be identical, even if you make one a midrange.
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post #28 of 48 Old 01-05-2010, 06:09 AM - Thread Starter
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Quote:
Originally Posted by kbgl View Post

That's a really nice cabinet!

I assume that it is a 2.5 design from what I see, but thought you said somewhere that it was a 3-way. Have you considered taking a shot at improving the x-over. Sometimes a small change can make a difference. Can you make out part values and layout of the x-over?

How loud do you want to play music? Do you want to go over about 90dB?

Can we get a closeup of the woofer where it is recessed into the box? Do you want to have the grills off on occasion? I would. If you do, I think both drivers should be identical, even if you make one a midrange.


I'm sure it's a 2.5 way.

Yeah they're nice, they have a really good WAF to my surprize as I thought they would be 'too big'. We A/B'd them to the PSB we normally have and both agreed that the Advent were lacking. I've moved these Advent to our music area and the PSB to the HT so I could get that hooked up. I was listening again to the Advent last night, and was thinking the same thing as you about a xover.

When we did a critical listening with music, I thought the PSB were rich and balanced, just about perfect overall except for a small lack of low end. The Advent seemed thinner by comparison, and had a hasher midrange especially in the vocals and electric guitars. I've heard people say these Advents "actually have a pretty good tweeter". The Advent actually sound pretty good in the HT, but I think its becaused of the pronounced mids.

Last night we were playing Wii, and I noticed that they were very clear overall, had a nice bottom end at times (but could/should be vastly improved for 8" big cabs) though the content was lacking there, and the tweeter really were very nice. If the cab was ported, and the mids could be changed via crossover, cabinet braced, etc it could make a huge difference. That said, I'm not sure if the lows and mids could be fixed without a driver change.

-Yes I have the grills off now and prefer it, although i'm not thrilled about the rather large grill guide cups. I would also prefer both drivers to be the same just for aesthetics alone.

-Not sure if I could make any kid of schematic, I can barely read one myself without much pain and research. LOL I took that closeup pic, and can supply more and try to read whats on everything.

-I can take any pics that would be helpful. I'll take out the driver and take some of the driver and the inside of the cab as well as the driver recess.

-I don't have a great sense of what 90dB is, but we don't really listen to this stereo very loud. When we do it's more for room filling rather than cranking if that makes sense. Loudest it would ever go is where you'd have to talk very loud for someone to hear you. My truck stereo is the cranker. I've got Morel MDT 12>Vifa TG>Dayton RS180 and an Illusion Audio reverse voice coil (extremely shallow) carbon fiber 12" sub. Each driver has a separate channel from two Helix amps with built-in xovers. All in a tiny mid-sized CREWcab truck. It has the massive limitations of a vehicle environment, but even without having my dash pods done yet, it has been so good as to give me that audiogeek warm fuzzy.
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post #29 of 48 Old 01-05-2010, 06:33 AM - Thread Starter
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If you reference the schematic pic, and what I know from looking at it:

(starting at upper right)
-KSC(I assume brand) 20mfd/100vdc

(below that)
-KSC 6mfd/100vdc

(directly left)
This is a fuse. I don't recall it's value but it was something like 1.5a or 7.5a 250v, I couldn't read it very well.

(below that)
black thing, I have no idea, not marked

(center vertical)
bigger black thing, no idea not marked. I'm asuming this is an inductor-it's a wire coil wrapped inside the black sheathing.

(top left)
same as the black one

(center left)
back of the binding posts, red is the one on the outside, black inside

(bottom left)
Looks like a resistor - KSC, 1(horseshoe symbol)J, 5w - I assume this is a 1 ohm resistor. The horseshow is the ohms symbol? This is the limit of my electronics knowledge. LOL Although I learn fast.

Thats about it for the crossover, other than what wire is hooked to what. I'll try to get another pic and map out which drivers wires go where when i take the drivers out for pics.

I keep meaning to ask, any recommendations for a book(s) on crossovers and or speaker design building? Enough to cover the basics?
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post #30 of 48 Old 01-05-2010, 09:23 AM
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The "Loudspeaker Design Cookbook" is a good one. I think Parts Express sells it.

I'd go for the 3-way option using the SEAS 8 for mid, and woofer. It's about a half inch bigger in diameter, so that should work. It sounds like a single 8 would be loud enough for what you are planning. Making it a 3-way will allow you to adjust the tonal balance more easily, and you gain a few more hz of bass extension. You would need to make a small box chamber for the mid, and attach it inside with glue, or maybe silicon. Might be like building a ship in a bottle since you would have to work through the woofer holes. Either way, you may want to replace the tweeter. It looks like it has a high x-over frequency. You will want to cross at about 2k. Maybe as high as 3k. Crossing low puts more stress on the tweeter.
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