Dayton Audio ND65-8 Actual vs Advertised

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Winkleswizard

Audioholic
Yeah, that is what I did, but noticed it really did not update. Re-ran as admin and works now.

Looked at one of your graphs and made me remember why I sent the minidsp application link earlier. The phase display is unfiltered and has artifacts in it. To sort this out, see the viewing phase section of that post.

Ww
 
J

joshk03

Audioholic
Well I went out and took new measurements in the same spot. It was pretty loud in the backyard today. The noise floor was about 70db. I adjusted to 75db on the pink noise as always, but that includes all the planes, cars, and pool pumps in the area. Unfortunately my neighbor runs their pool pump 24 hours a day all summer. Fools. Red is version1, blue is version2 today. Not sure I trust the environment though.
 
Johnny2Bad

Johnny2Bad

Audioholic Chief
Yay. Today I got my UMIK microphone and my proper insulation. Sadly, my version2 cement enclosure is still too wet for assembly. But version1 got the full test!
I went outdoors and fired at the UMIK from 1 meter away. The noise floor in my backyard seems to be 55db according to the umik/rew SPL meter. That's louder than my attic, but hopefully acceptable.

... {snip} ...

I'm not liking the notches at 260 and 380, but they are acceptable? I am really hoping the version2 cement enclosure with it's asymmetric spiral rib interior will be even better. But overall I am satisfied with my progress. Suggestions welcome!
The notches *might be* acceptable. Broadly speaking peaks are more objectionable sonically than notches, and narrow (low Q) aberrations less objectionable than broad ones.
 
J

joshk03

Audioholic
The notches *might be* acceptable. Broadly speaking peaks are more objectionable sonically than notches, and narrow (low Q) aberrations less objectionable than broad ones.
Good to hear.
So I'm thinking these would make good satellite speakers since they are easy to position without giving up floor space. How does their frequency response compare to pre-built options? Is their lack of bass typical of satellite speakers, or a concern?
 
W

Winkleswizard

Audioholic
For a first DIY speaker project, I think you have done quite well. A full range design involves compromises and you have balanced them well. I have looked at other comparable drivers and did not find anything around the same price as the ND-65 that was clearly superior.

If you mount them in a ceiling corner, you should get some bass reinforcement. This would also determine whether you might need some filtering to flatten the room response. If using an AVR with auto-eq, it should flatten the response without need for using any passive components. Shy of using another driver or a minidsp, this is the easiest way to deal with the ND-65 breakup at 8k.

Ww
 
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Johnny2Bad

Johnny2Bad

Audioholic Chief
Good to hear.
So I'm thinking these would make good satellite speakers since they are easy to position without giving up floor space. How does their frequency response compare to pre-built options? Is their lack of bass typical of satellite speakers, or a concern?
The Frequency Response (FR) curve in your enclosure seems typical of small full range driver systems. Some listening would be in order, it's really difficult to say how you would like them based on FR alone (there is a bit more with regard to measurement that tells the whole story).

With multi-way driver systems, there is an opportunity to tune the sonics via the crossover (and most professional speaker designers do tune based on ear after the theoretical Xor is applied); you won't have that option, at least to the same extent.

You can add some Xor elements to a full range (FullR) driver, that can alter FR but it kind of takes away from the reason for choosing FullR in the first place (no crossover elements make for better sonics, certain difficult to measure qualities, like "immediacy" and "realism" which FR systems tend to possess would probably be diminished).

The obvious option would be to add a sub if you feel it's necessary, but you might find they are fine as is. Note that many systems we are OK with everyday (laptops, cellphones, television built-in speakers, portables) will have similar response (and via measurement, often worse) as yours seem to be exhibiting, and they can still be satisfying.
 
J

joshk03

Audioholic
I had listened to them and decided speech sounded great, music sounded good, and action sequences in movies sounded lame.
I took multiple measurements again outdoors from different angles. I smoothed them psycho-acoustically, then averaged them. Then I generated a parametric EQ set. Then I installed Equalizer APO and input the numbers. I ran REW again and took multiple measurements again. Sure enough, I got great looking results. I just finished minutes ago, but I have to say, clicking the equalizer on made my eyes a little wider. It sounds sweet now. And that's just one speaker, no stereo yet. :) Have a look at the REW data now :)
I'm learning fast.
And I ordered a Rythmik Sub last night :D
 
Johnny2Bad

Johnny2Bad

Audioholic Chief
Just be aware that smoothing makes for nice looking graphs but the peaks and dips are still there, you just don't see them on a smoothed graph ... it's why manufacturer's literature includes smoothed graphs almost exclusively.
 
J

joshk03

Audioholic
Here's the data from before the parametric equalizer. Psyco-acoustic smoothing too. But yes I agree.
 
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TLS Guy

TLS Guy

Seriously, I have no life.
Here's the data from before the parametric equalizer. Psyco-acoustic smoothing too. But yes I agree.
For a full range 2.5" driver that is a very good response. Way better than Bose. It should be a good small satellite. For HT a decent sub or two that can be crossed at 150 Hz will be pretty much mandatory.
 
J

joshk03

Audioholic
For a full range 2.5" driver that is a very good response. Way better than Bose. It should be a good small satellite. For HT a decent sub or two that can be crossed at 150 Hz will be pretty much mandatory.
Good to hear. I'm glad you're still here, I was looking forward for an experienced opinion on the data.
I think I will be good with 1 sub since these little speakers can't go crazy loud anyway. So hopefully the Rythmik FVX15 I ordered will be oversized for this setup even though it has to fill 8625 cu ft. If not, I guess I can add a matching second someday.
 
KEW

KEW

Audioholic Overlord
Good to hear. I'm glad you're still here, I was looking forward for an experienced opinion on the data.
I think I will be good with 1 sub since these little speakers can't go crazy loud anyway. So hopefully the Rythmik FVX15 I ordered will be oversized for this setup even though it has to fill 8625 cu ft. If not, I guess I can add a matching second someday.
My main concern on the sub is how well it can perform up to (and somewhat beyond) 150Hz.
I have no reason to believe it won't, but not all sub designs do.
You might give Rythmik a call to verify if you had not discussed it.
 
J

joshk03

Audioholic
Yea that will be important with these speakers. But according to the graphs they publish, it can go to 150 without dropping off, and to 300 with about 3db of dropoff. Though they print LFE to 200hz and LineIn to 90hz.
I'm not afraid to return anything that disappoints.
http://www.rythmikaudio.com/FVX15_specs.html
 
Johnny2Bad

Johnny2Bad

Audioholic Chief
That curve looks fine to me, for what it is. The dip at 350~600 Hz is right in the vocal range but you may not be bothered with a little recessive response there, in fact you may even find that the speaker sounds strong in the midbass because the response there is up vs the vocal range. As for the top end, 7~10KHz, not a huge problem. The other thing is you want balance ... in other words a speaker with extended bottom but no top end doesn't sound good, nor does one with extended highs and no bottom. In your case even the dips appear somewhat symmetrically referenced to 1 KHz, so it should sound balanced, which is a good thing.
 
KEW

KEW

Audioholic Overlord
Yea that will be important with these speakers. But according to the graphs they publish, it can go to 150 without dropping off, and to 300 with about 3db of dropoff. Though they print LFE to 200hz and LineIn to 90hz.
I'm not afraid to return anything that disappoints.
http://www.rythmikaudio.com/FVX15_specs.html
I'm not sure I understand the interpretation of the line in vs LFE in.
One possibility is LFE In means the sub is full range and depends on your AVR to perform all crossover function.

I like the juxtaposition of those 2.5" lifestyle "eggs" and the imposing Rythmik.

So how close of a match are they?:cool::
Ostrich eggs are the largest of all bird eggs (and by extension the yolk is the largest single cell),though they are actually the smallest eggs relative to the size of the adult bird. On average they are 15 centimetres (5.9 in) long, 13 centimetres (5.1 in) wide, and weigh 1.4 kilograms (3.1 lb).
 
J

joshk03

Audioholic
The line-in is at the full mercy of the control panel, the LFE seems to be a full-range input that bypasses that and lets the AVR to do the special tricks.
I know my wimpy speakers are odd on such a powerful system, but my wife and I weren't comfortable pimping it all the way just yet. I don't think I've ever broke my rule of not buying something that I know will get replaced ever before. But being able to design a matching set of 7 speakers for about $140 + labor and have some fun doing it is fine in my book. And I could probably e-bay them and make back parts and labor.
I don't have the numbers on me, but yea, that ostrich egg is very close. These may be a bit smaller. :)
 
J

joshk03

Audioholic
I checked, the outside is 5" long, the diameter is 4.5", and the weight is 1.75 lbs with the speaker installed.
 
W

Winkleswizard

Audioholic
Yea that will be important with these speakers. But according to the graphs they publish, it can go to 150 without dropping off, and to 300 with about 3db of dropoff. Though they print LFE to 200hz and LineIn to 90hz.
I'm not afraid to return anything that disappoints.
http://www.rythmikaudio.com/FVX15_specs.html
Not sure you ever really mentioned what you are trying to do with your speaker. The requirements are different if you are just doing sound reinforcment for music vs home theater. So please explain.

In any case, our hearing starts to localize frequencies above about 150 Hz. If you crossover to your speakers above that, the resulting sound quality will be mediocre. This is will be exacerbated if your really do need to fill almost 9000 ft3. Given this volume you are likely to need more than one subwoofer for good sound. But I sense you have a bigger challenge...

While your speaker design is decent from a frequency response perspective, it has some significant limitations as far as output capability. It has relatively low sensitivity coupled with limited power handling. Simply put, it will not be able to play very loud even if you give it power. If you plan to use several of them, you might be able get by for background listening levels, but not for anything really loud in your room volume.

Whether you are trying to do home theater or just music will determine the best direction for your equipment, but let us know and will help you adjust.

Ww
 
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J

joshk03

Audioholic
It's been mentioned in my other threads, but my main goal is to play background music all day long. We very rarely turn on the TV. And I almost never sit down over on the couch.
There are so many speaker choices and I don't know if a high end 2.1 system or high end 7.1 would fill the room best. So for the time being I am demoing 7.1 with my DIY speakers. We have the money to drop the extra ~3k on a high end speaker system, but don't want to get it wrong.
One strong possibility is that I will move to a 2.1 setup, but not remove the DIY surround speakers. Then we can activate them for a movie if we really want.
 
W

Winkleswizard

Audioholic
Ok. This helps a bit. It can be challenging (and more expensive) to do a system by starting small and expanding, but think I get the gist of your thinking. Given the size of your room, a 2.1 system using your speakers and a subwoofer is likely going to come up shy. I suggest you should plan for having at least a 5.2 system, maybe 7.2. You are either going to need many of your smaller speakers or larger mains.

Hope this helps!

Ww
 
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