Dayton rs180/ seas 29taf/w 2 way bookshelf design

[tyroneshoes]

I wanted to share this design because it sounds amazing and is my favorite 2 way design I've built. Measures very well. Is very detailed but not shrill and has very good midrange for an all metal 2 way with a 7". Great first project.

It uses the rs180 and seas 29taf/w seen here

SEAS Prestige 29TAF/W (H1322) Aluminum/Magnesiun Dome from Madisound

Here's a pic of mine (and yes I did paint the rs180's phase plus for aesthetics)



And you can see the matching center channel and my rs sub I can share if interested.

Now lets get down to it. Here's the crossover design and fr



I use jantzen air core coils and dayton caps and resistors in this design.

Pretty damn impressive for a speaker that costs around 300 to build.

Works well in sealed .50cuft if using a sub.

Ported in .75 cuft and tune to liking. You can get good bass extension from the rs180.

Model it up and see what you prefer.

I also have a design for a mini monitor using the rs125 and vifa xt neo seen here



http://www.diymobileaudio.com/forum/...mers-pros.html

Any questions, feel free. Im pretty sure youll love these.

[Hillbilly SQ]

I was just thinking about this design the other night. Will you share the schematic for the center as well?

[tyroneshoes]

Sure. The center is a 2.5 design using two rs125 and same tweeter.

[seagrasser]

Your rs-180 design, is that the 8 or 4 ohm version? I assume the 8 ohm version, but wanted to be sure.

[Hillbilly SQ]

What are the specs on the box for the center? And does it have to be a certain height or can it be not much taller than the flange of the mids?

[tyroneshoes]

Originally Posted by seagrasser

Your rs-180 design, is that the 8 or 4 ohm version? I assume the 8 ohm version, but wanted to be sure.

They're the shielded 8 ohm rs180s

[tyroneshoes]

Originally Posted by Hillbilly SQ

What are the specs on the box for the center? And does it have to be a certain height or can it be not much taller than the flange of the mids?

I used this enclosure design but made small adjustments due to the slightly larger tweeter in my design.



You can make them less tall if you increase the depth.

[Hillbilly SQ]

One more question and I should know this but: does 330uH equal 3.3mH? It's been a while since I took basic electricityother than that I can read a schematic like a pimp.

[bikinpunk]

No.

u = micro (10^-6)

m = milli (10^-3)

[Hillbilly SQ]

So 300mH=.3uH?

[tyroneshoes]

Originally Posted by Hillbilly SQ

One more question and I should know this but: does 330uH equal 3.3mH? It's been a while since I took basic electricityother than that I can read a schematic like a pimp.

1000 uH = 1 mH, therefore 330 uH = 0.33 mH

[King Nothing]

Is that 300 per speaker or 300 for a pair? just wondering

[Hillbilly SQ]

Originally Posted by King Nothing

Is that 300 per speaker or 300 for a pair? just wondering

I added up the parts on pe and it's around that for the pair. Very reasonable.

[Hillbilly SQ]

Originally Posted by tyroneshoes

1000 uH = 1 mH, therefore 330 uH = 0.33 mH

Thanks. Bikinibutt hinted and I figured it out but now I know for sure.

[MiniVanMan]

Originally Posted by Hillbilly SQ

What are the specs on the box for the center? And does it have to be a certain height or can it be not much taller than the flange of the mids?

Any of these designs are designed with a specific baffle width. That's a fairly critical calculation.

As for the center, a 2.5 way center is a much better idea than an flipped down MTM. HOWEVER, a typical 2.5 way uses the ".5" as compensation for baffle step (BSC). Like I said before, baffle width is critical in this calculation. So, what happens when you put said speaker. with a specific amount of BSC applied for a specific baffle width, on top a large TV?? Or worse, right up against a wall?

Things to consider before settling on any loudspeaker or loudspeaker design.

Center channels are the HARDEST thing to implement well into a home theater. Be prepared to get very frustrated the more you read into them.

[Hillbilly SQ]

Originally Posted by MiniVanMan

Any of these designs are designed with a specific baffle width. That's a fairly critical calculation.

As for the center, a 2.5 way center is a much better idea than an flipped down MTM. HOWEVER, a typical 2.5 way uses the ".5" as compensation for baffle step (BSC). Like I said before, baffle width is critical in this calculation. So, what happens when you put said speaker. with a specific amount of BSC applied for a specific baffle width, on top a large TV?? Or worse, right up against a wall?

Things to consider before settling on any loudspeaker or loudspeaker design.

Center channels are the HARDEST thing to implement well into a home theater. Be prepared to get very frustrated the more you read into them.

Tyrone has his center laying the same way 99.9% of everyone else has theirs. Is this wrong on his part? Seriously, I'd like to know before I do the center in this thread.

[MiniVanMan]

Originally Posted by Hillbilly SQ

Tyrone has his center laying the same way 99.9% of everyone else has theirs. Is this wrong on his part? Seriously, I'd like to know before I do the center in this thread.

Depends on the design. A typical D'Appolito type MTM has horrible vertical polar response. That means when you flip it on it's side any sound left or right of the speaker will be severely degraded. Think of it as off-axis response. They have very good horizontal polar response though, so they are designed to be a loudspeaker that stands vertically.

The design Tyroneshoes is talking about is not a D'Appolito type MTM. It's a 2.5 way, which is considerably different, even though they look the same.

The way they both approach baffle step is completely different, and is extremely important to be aware of when you consider where to place your center channel.

Basic Guide to Crossovers (Part 2)

There's a reason I make those threads. It's just so much easier to link back to than keep relating the same information over and over.

Take a look at the manufacturer response of the Dayton RS180, and then look what happens when I put it on a 9" wide baffle (which is very thin by the way for that sized driver). Notice the 6-7 db drop in response from 1khz to about 100-150 hz? The baffle is causing that. The wider the baffle, the lower the the peak in baffle step, but it will always be there. Well, if you put a 4" driver on a 10 foot baffle you can probably avoid it, but that's a bit unrealistic for a loudspeaker.

So, we can apply filters to compensate for the baffle step. When we do so, we lose that 6 db, and effectively drop the sensitivity of our loudspeaker. In the case of the Tyroneshoes design, another driver was added to only play within the bandwidth of the baffle step, causing a 3-4 db boost in that area. We're left with a small amount of baffle step, which is fine.

Now the problem arises in this design, that while it's not a D'Appolito design, and should therefore have better vertical polar response, it is VERY subject to changes in baffle width. That extra driver is a precision strike against the baffle step, so any deviation in baffle width will change the entire system.

Got it? Good.

4.1 for the win here bro.

In a perfect world we isolate our loudspeakers from all surrounding walls and flat surfaces. If I had to pick a MTM configuration for a center channel, I'd definitely do a 2.5 way. I'm just stating the facts, and variables that you need to take into account. That TV above his center channel IS causing fluctuations in his response, as is his floor. Just be aware of that. It's unavoidable frankly, but picking the right design has a lot to do with actual placement of the loudspeaker.

Oh, and 99% of the people out there running center channels on their sides do so because they are ignorant, and believe what the audio companies tell them.

Go to any audio store. I don't care if it's Best Buy. Go to their listening room. Have them only hook up one floor standing loudspeaker. Step to the left and right of that loudspeaker and note the off-axis response. Now, have them hook up the center channel that's flipped on it's side. Note the left and right off-axis response. Ask the guy to turn the center channel vertical, then note the off-axis response.

Report back with your results.

[tyroneshoes]

Originally Posted by MiniVanMan

Depends on the design. A typical D'Appolito type MTM has horrible vertical polar response. That means when you flip it on it's side any sound left or right of the speaker will be severely degraded. Think of it as off-axis response. They have very good horizontal polar response though, so they are designed to be a loudspeaker that stands vertically.

The design Tyroneshoes is talking about is not a D'Appolito type MTM. It's a 2.5 way, which is considerably different, even though they look the same.

The way they both approach baffle step is completely different, and is extremely important to be aware of when you consider where to place your center channel.

Basic Guide to Crossovers (Part 2)

There's a reason I make those threads. It's just so much easier to link back to than keep relating the same information over and over.

Take a look at the manufacturer response of the Dayton RS180, and then look what happens when I put it on a 9" wide baffle (which is very thin by the way for that sized driver). Notice the 6-7 db drop in response from 1khz to about 100-150 hz? The baffle is causing that. The wider the baffle, the lower the the peak in baffle step, but it will always be there. Well, if you put a 4" driver on a 10 foot baffle you can probably avoid it, but that's a bit unrealistic for a loudspeaker.

So, we can apply filters to compensate for the baffle step. When we do so, we lose that 6 db, and effectively drop the sensitivity of our loudspeaker. In the case of the Tyroneshoes design, another driver was added to only play within the bandwidth of the baffle step, causing a 3-4 db boost in that area. We're left with a small amount of baffle step, which is fine.

Now the problem arises in this design, that while it's not a D'Appolito design, and should therefore have better vertical polar response, it is VERY subject to changes in baffle width. That extra driver is a precision strike against the baffle step, so any deviation in baffle width will change the entire system.

Got it? Good.

4.1 for the win here bro.

In a perfect world we isolate our loudspeakers from all surrounding walls and flat surfaces. If I had to pick a MTM configuration for a center channel, I'd definitely do a 2.5 way. I'm just stating the facts, and variables that you need to take into account. That TV above his center channel IS causing fluctuations in his response, as is his floor. Just be aware of that. It's unavoidable frankly, but picking the right design has a lot to do with actual placement of the loudspeaker.

Oh, and 99% of the people out there running center channels on their sides do so because they are ignorant, and believe what the audio companies tell them.

Go to any audio store. I don't care if it's Best Buy. Go to their listening room. Have them only hook up one floor standing loudspeaker. Step to the left and right of that loudspeaker and note the off-axis response. Now, have them hook up the center channel that's flipped on it's side. Note the left and right off-axis response. Ask the guy to turn the center channel vertical, then note the off-axis response.

Report back with your results.

Good info and right on point. I went from a mtm horizontal design and hated it. Just didnt sound right and was a way different tone (especially in the voice range which is crucial for a center). This 2.5way design improved on the previous 2 way mtm but I found myself switching back to 4.1. The horizontal mtm will never sound as good as a vertical speaker. I just said screw it, and I opted to get a NAD amplifier to power my mains, and put my cable box where the center is in that pic and the amp on the shelf. I dont miss the center at all. As far as "center" horizontal mtm speakers go, its a great design but there are limitations that someone who needs everything to sound perfect just cant overcome with the typical horizontal mtm. Most people cant tell but I dont think we're the average audio consumer.

Personally I use a 4.1 myself and have this center in my closet. Its a good speaker but I just liked the sound from the 2way rs180s more. I believe that if I do plan to ever rebuild a center channel Ill use a point source or fullrange driver for the very reasons stated above.

As far as the baffle width for the two way, these were designed with the .75 cuft PE boxes as the model and I recommend you follow those measurements. My baffle is slightly wider because I originally built these the same time I built my previous entertainment unit and they had to be a specific size.

I recommend you start with the 2 way speakers and begin the learning process. Just like car audio, you learn as you go. Lots of good info out there. Building home speakers and designing crossovers are far more involved than car audio because you have a much quieter listening environment and you can make the design and finish almost like an art. It is an art.

Both of these 2 way designs are great, low cost introductions to the process.

[Hillbilly SQ]

Parts Expressayton TW-0.50BK 0.50 ft³ 2-Way Cabinet Gloss Black
Is this a good enclosure to copy? Since I have a sub going in that should be able to play up into the 100hz range cleanly if needed going sealed shouldn't be an issue right? Afterall it says in the op that .5 sealed is fine if running a sub. And the enclosure the crossover was modeled for was the dayton box.

[tyroneshoes]

Originally Posted by Hillbilly SQ

Parts Expressayton TW-0.50BK 0.50 ft³ 2-Way Cabinet Gloss Black
Is this a good enclosure to copy? Since I have a sub going in that should be able to play up into the 100hz range cleanly if needed going sealed shouldn't be an issue right? Afterall it says in the op that .5 sealed is fine if running a sub. And the enclosure the crossover was modeled for was the dayton box.

Only thing is the original design has a 10" wide baffle (PE .75 cuft) while the .5cuft enclosures are 8.5" wide.

These speakers sound better ported even if you crossover as high as 100hz. I highly recommend you follow the 10" wide baffle and subtract from the depth if you are positive you want to go sealed.

Personally, if youre going to do it, I say .75 cuft tuned to mid 40's. I cross over at 80hz and these speakers can get much lower. Midbass is enhanced as well vented. My speaker placement/cutouts are very similar to the 2 way usher design on PE as far as measurements and port installation.

[Hillbilly SQ]

Ok got the cut sheet planned out to do a direct copy of the .75 cabinets from pe. How does a 45hz tuning with a 2.5" wide port sound? It's gotta be better than my current 5" jbl 2-ways because I just did some number crunching and playing around with an online port calculator and they're tuned to around 85hz lol.

[tyroneshoes]

Originally Posted by Hillbilly SQ

Ok got the cut sheet planned out to do a direct copy of the .75 cabinets from pe. How does a 45hz tuning with a 2.5" wide port sound? It's gotta be better than my current 5" jbl 2-ways because I just did some number crunching and playing around with an online port calculator and they're tuned to around 85hz lol.

tuned to 39 hz

2" precision port 5.8 inches long