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Loudspeaker DesignDesigning The Monochromes

By: Beau Seigfreid

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As I went down the list of drivers on the list, I also put the drivers through modeling on

WinSpeakerz to see just how they would react to the vented enclosure. The majority of

the woofers had a very similar response to the enclosure. The woofers frequency

response charts are as follows;

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Woofers Price F3 dB Sensitivity

1. Dayton Audio RS225-8 8" ReferenceWoofer

$57.42 28 Hz 86 dB

2. Dayton Audio DC160-8 6-1/2" ClassicWoofer

$21.78 34 Hz 88 dB

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I; Dayton Audio ST210-8 8" Series IIWoofer

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Figure 4.1 Woofer Selections

Dayton Audio RS225-8 8" Reference Woofer This speakers frequency plot can be

found on the next. I really wanted an 8 woofer to go with a set of tweeters because I

really wanted that bass response in my set of drivers. I love the response ability of these

speakers but they have some significant problems before 1 kHz with a very steep roll-off.

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Figure 4.2 - Dayton Audio RS225-8 8" Reference Woofer

The next drivers I chose were from Dayton Audio just like all the other drivers in this

paper will be. This woofer is the Dayton Audio DC160-8 6-1/2" Classic Woofer. I

wanted to push myself to stick with a particular brand of speaker in order to build loud

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speakers that had drivers that were meant for each other, so to speak. This speaker is

smaller than the speaker I intended to have.

Figure 4.3 - Dayton Audio DC160-8 6-1/2" Classic Woofer

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The speakers I got really excited to get my hands on were the Dayton Audio ST210-8 8"

Series II Woofers. Amazingly, these ones also have the dip similar to the first 8.

Figure 4.4 - Dayton Audio ST210-8 8" Series II Woofers

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After all the debate, I decided to go with the next set of drivers which are the Dayton

Audio DS215-8 8" Designer Series Woofer Speaker. The frequency response plot looks a

bit easier to work with when it comes to a cross-over at about 1800 Hz. The f3 of the

driver is fairly impressive as well at 36 Hz.

Figure 4.5 - Dayton Audio DS215-8 8" Designer Series Woofer Speaker

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Figure 4.6 A Modeled Dayton Audio DS175-8 6 1/2" Designer Series Woofer Speaker

That driver looks like this when modeled in a 18 x 14 x 14 (H x W x D) enclosurewith a 1.5 inch diameter/ 2.18 circular vent. The bass boost is what I want in order toachieve a big, warm sound. And by dropping the diameter of the speaker from 8 to 6 -1/2, the price dropped along with the sensitivity. This ended up with my woofer andtweeter both having the same sensitivity.

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Tweeters Price dB Sensitivity

1. Dayton Audio ND28F-6 1-1/8"Neodymium Dome Tweeter

$23.29 88 dB

2. Dayton Audio DC28F-8 1-1/8" SilkDome Tweeter

$19.75 89 dB

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N; Dayton Audio RS28A-4 1-1/8"Aluminum Dome Tweeter

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Figure 5.1 Tweeter Selections Table

I ended up narrowing down my tweeter selections to the two silk tweeters based on price

and quality. The first of the two is this tweeter, the Dayton Audio DC28F-8 1-1/8" Silk

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Dome Tweeter. The tweeter looks to have some problems as the frequencies enter the

very high ranges.

Figure 5.2 - Dayton Audio DC28F-8 1-1/8" Silk Dome Tweeter

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