My first build thread. The Ocelot(s).

[zieglj01]

I like that about using Denim insulation - that looks interesting
and easy to handle

 

[monkish54]

How did you make your openings?

Router. The tweeter cutout i did by hand. It was a HUGE pain in the *** but it came out perfectly.

As for the woofer, i built a circle guide when i was building my subs. I attach it directly to the router.

I like that about using Denim insulation - that looks interesting
and easy to handle

It is very easy to handle. I bought some of the 5" thick variant to hang in my bedroom when my Philharmonics were in there. Now that i dont need them, i grabbed a little off the bottom of one of the panels. I have 3 panels that were never used and 3 that are no longer used. I have plenty of cabinet stuffing hanging in my room - now that's dedication!!

 

[Swerd]

Router. The tweeter cutout i did by hand. It was a HUGE pain in the *** but it came out perfectly.

I've never known anyone who did good work with a router, who did that good work free hand .

There is a guided way to rout out flush-mount holes for irregular face plates like your tweeter has. I have an old link that shows how to do it, but I think it's dead now. Does anyone have a fresh link for this?

DIY Home Audio, DIY Car Audio, DIY iPod Integration, and Do It Yourself Whole House Audio

I also saved the directions in a word file, if you PM me with an email address, I'll send it to you.

You will need a ¼" router bit and a ¾" template collar bushing. You should be able to find inexpensive sets of these template guides such as these:

PORTER-CABLE 42000 9-Piece Template Guide Kit - Amazon.com

Kempston 99000 10 pcs Solid Brass Template Guide Kit With Adaptor - Amazon.com

 

[sawzalot]

I don't think he would ever answer yes since that would be a violation of yetanother AH policy

How did he/she know that ridikulas was even a person, the question was, Are you ridikas?? Hmmmmmm

 

[Adam]

How did he/she know that ridikulas was even a person, the question was, Are you ridikas?? Hmmmmmm

Maybe it was the capital "R" in the question.

 

[cpp]

Maybe it was the capital "R" in the question.

Could be... You know I just don't understand, well maybe I do, the internet gives people a sort of hidden macho power hiding behind a keyboard....But like anything in life, you have to earn that power or for a better word, 'respect'. Pissing off the masses is not the way to achieve respect, it's takes time and if you do offer up criticism you offer it constructively not in a condemning or an attacking manner as they say, you lead by example...

 

[monkish54]

The Build Continues!!On this week's episode:

MEASUREMENTS!
Okay, done being an idiot.

Tweeter at 1 meter:


Woofer at 1 meter:



Woofer Nearfield:



I'm not thrilled with the tweeter's response above 12khz in HOLMImpulse. REW has, what I believe to be, a more accurate response up high but below the responses are nearly identical and HOML is easier to read so I'm going to model using HOLM.

I will have DATS measured impedance uploaded before the day is up.

Does anyone know how to do a 2.83V measurement in any free measurement software? I want to determine the driver's sensitivity.

 

[Swerd]

I'm not thrilled with the tweeter's response above 12khz in HOLMImpulse. REW has, what I believe to be, a more accurate response up high but below the responses are nearly identical and HOML is easier to read so I'm going to model using HOLM.

I will have DATS measured impedance uploaded before the day is up.

Does anyone know how to do a 2.83V measurement in any free measurement software? I want to determine the driver's sensitivity.

Your measurements look good. Nice work. Don't worry about the measured response above 12 kHz. You can't, and maybe shouldn't, do anything about that. It's a good tweeter.

What you should do, is get off-axis measurements, at ~30° and ~45°, of the woofer. Find the frequency at which the off-axis response drops by 3 or more dB. If you cross to the tweeter at that frequency, you will have a speaker with excellent dispersion over the midrange, and you will have speakers that, in stereo, create good images.

 

[charmerci]

I'm not thrilled with the tweeter's response above 12khz in HOLMImpulse. REW has, what I believe to be, a more accurate response up high but below the responses are nearly identical and HOML is easier to read so I'm going to model using HOLM.

Could that be from the high frequency reflections off of the front surface of the speaker/cabinet?

Diffraction Be Gone Rocks! - Audiophile Review

 

[Alex2507]

Why did you call it the Ocelot?

That's the outfit he likes to wear on the weekends.

You can expect all his speaker projects to have animal names ... The Pandas, Boca Raton, The Turtles, etc.

 

[monkish54]

Your measurements look good. Nice work. Don't worry about the measured response above 12 kHz. You can't, and maybe shouldn't, do anything about that. It's a good tweeter.

There is a little I can do, but what you see is not what I am not thrilled about. It's what you don't see.

In Zaph's and Dayton's measurement the RS28A has a dip from 12khz to around 17khz and then shoots back up around 20khz. In my HOLM measurements the tweeter falls off around 12khz and shoots down. In my REW measurements I share the large dip with Dayton and Zaph and thus I think those are more accurate. It doesn't matter much for crossover design, so I'm using the HOLM measurements.

What you should do, is get off-axis measurements, at ~30° and ~45°, of the woofer. Find the frequency at which the off-axis response drops by 3 or more dB. If you cross to the tweeter at that frequency, you will have a speaker with excellent dispersion over the midrange, and you will have speakers that, in stereo, create good images.

I intend to.

This is the reason I chose the RS28 -- it can cross nice and low. I was thinking around 1.5khz where both the woofer and tweeter have very wide dispersion, but it may change depending on what my measurements show.
Woofer Impedance

 

[monkish54]

Thread's not dead yet, gentlemen. I've run into a few technical difficulties. Build will continue shortly.

In other news, i finally picked up that quarter.

 

[Adam]

Thread's not dead yet, gentlemen. I've run into a few technical difficulties. Build will continue shortly.

In other news, i finally picked up that quarter.

Why are we whispering? Did you see Alex in the house?

 

[monkish54]

First of all, whoever left that rep and comment, you are epic.

Secondly, I have modeled a very nice response using about $40 worth of XO parts, however I had to add 10db of BSC resulting in a VERY insensitive speaker. ~75db if my scale is right.

10db of BSC seems questionable to me. I was a little worried that, for whatever reason, anechoically 10db is what is needed but in-room would be way off balance, but the raw response of the ZA14W08 with the cabinet in place as a center also has the woofer response at 100hz about 10db down. Considering the front baffle was about 2' 4" in front of a 65" TV and 100hz has a wavelength of 11', I am very confused as to how I am losing 10db of output at 100hz. Any suggestions?

IN-ROOM ZA14W08



Overall Response with BSC (5db chart)

 

[BoredSysAdmin]

I've never known anyone who did good work with a router, who did that good work free hand .

There is a guided way to rout out flush-mount holes for irregular face plates like your tweeter has. I have an old link that shows how to do it, but I think it's dead now. Does anyone have a fresh link for this?

DIY Home Audio, DIY Car Audio, DIY iPod Integration, and Do It Yourself Whole House Audio

Flush mounting Dayton 5 1/4
https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=2&cad=rja&ved=0CDgQFjAB&url=http://audioroundtable.com/forum/pdf.php?th=5561&&ei=zHjWUqn5BaPksASY_IHIAQ&usg=AFQjCNGUxXHd_7m91oh0_WkYTaJabYG4eQ&sig2=qiliddANqPSgS1kM1Rw1Ng&bvm=bv.59378465,d.cWc