Introducing Denotiva DIY speakers!

[Bryguy]

Iirc PE won't accept returns on their stuff unless they deviate beyond 20% manufacturer stated spec. I know it's not your intention to return them, but as far as PE is concerned your sig180's are within "industry standard" of consistency

 

[RickS]

Iirc PE won't accept returns on their stuff unless they deviate beyond 20% manufacturer stated spec. I know it's not your intention to return them, but as far as PE is concerned your sig180's are within "industry standard" of consistency

Gotcha and do not plan to return. PE’s opp is to get some significant positive Signature series exposure or dinged on a quality issue (again). Really did not expect any reparation personally but to wanted to give them a chance to take corrective action. I was impressed with the abuse they took during burn-in but at 48 Hz, Fs is just at the 20% mark. Does not cut it for me.

 

[Dave Bullet]

How has your enclosure alignment changed with the different set of pre and post and heavy break in parameters? I remember Vance writing that the Vas - Qts - Fs relationship largely stays the same resulting in very similar responses.

 

[a4eaudio]

Have you modelled them with your T/S parameters vs the mfg's?

Here are my sims...green and blue are actual parameters (Fs 49 and 47Hz) vs manufacturers parameters (Fs 40.5Hz).
0.65 cf, Fb 45Hz, xmax at 35 watts. About 0.7db difference between green and red lines.

 

[Dave Bullet]

Well that's good. If linear response and non linear distortion measure consistently then the actual T/S parameters don't really matter

 

[a4eaudio]

Iirc PE won't accept returns on their stuff unless they deviate beyond 20% manufacturer stated spec.

PE has a no-hassle return policy for 60 days. But if they are not defective, shipping is on your dime.

 

[Bryguy]

PE has a no-hassle return policy for 60 days. But if they are not defective, shipping is on your dime.

You're right. I misspoke. They consider items within 20% spec a properly functioning unit

 

[RickS]

How has your enclosure alignment changed with the different set of pre and post and heavy break in parameters? I remember Vance writing that the Vas - Qts - Fs relationship largely stays the same resulting in very similar responses.

Sounds like reasonable generalization and Vance has much more driver experience than I. Have not remeasured (notably Vas) as I have real measurements (and can hear) the lack of bass. Have had plenty of drivers (including other Dayton woofers) and have not had any others that missed their mark so badly.

Have you modelled them with your T/S parameters vs the mfg's?

Here are my sims...green and blue are actual parameters (Fs 49 and 47Hz) vs manufacturers parameters (Fs 40.5Hz).
0.65 cf, Fb 45Hz, xmax at 35 watts. About 0.7db difference between green and red lines.

View attachment 380793

Sims are nice starting points, but am working with the real speaker and it is not meeting my goals. Along with the driver’s higher Fs, am using a smaller box than is optimal and slightly shorter port than I targeted originally. As I mentioned, there are some other factors (like the crossover) that might be used to help, but would involve more complexity than is my goal as well.

So, if faced with the choice between a marginal driver and better suited one for this design, not going to get heroic to try to make the SiG180 work. If it does for you, look forward to seeing your design.

 

[a4eaudio]

Sims are nice starting points, but am working with the real speaker and it is not meeting my goals. Along with the driver’s higher Fs, am using a smaller box than is optimal and slightly shorter port than I targeted originally.

To clarify, I didn't mean to suggest that the difference does not matter for your build. Just to show that for at least one specific box size and tuning it will work okay. A 0.65 cf box is larger than I was targeting for my own build and I don't think the actual TS parameters are going to work well much smaller, which I think is consistent with your findings.

 

[Dave Bullet]

I still wonder if you are missing a little BSC? There seems to be a 2dB rise in your (Assumed gated) measurements from 200Hz to 1KHz. Of course actual in room may mitigate this. I'm just trying to understand what your bass response is, what you expected to identify where / why it is missing the mark so badly.

Can we see either a ground plane (6dB adjusted) or quasi-anechoic full range measurement of the speaker? Maybe your nearfield port and woofer (and combined) measurement, with woofer gated farfield (with woofer crossover ok).

With only 200Hz and up measurements, we're not getting a full picture.

 

[RickS]

I still wonder if you are missing a little BSC? There seems to be a 2dB rise in your (Assumed gated) measurements from 200Hz to 1KHz. Of course actual in room may mitigate this. I'm just trying to understand what your bass response is, what you expected to identify where / why it is missing the mark so badly.

Can we see either a ground plane (6dB adjusted) or quasi-anechoic full range measurement of the speaker? Maybe your nearfield port and woofer (and combined) measurement, with woofer gated farfield (with woofer crossover ok).

With only 200Hz and up measurements, we're not getting a full picture.

Yes and clearly you have not read or fully understood my earlier posts. I have other projects that require my attention. After I get another readout on the SIG180 will make a decision on next steps and share.

 

[Dave Bullet]

Yes and clearly you have not read or fully understood my earlier posts. I have other projects that require my attention. After I get another readout on the SIG180 will make a decision on next steps and share.

Well, I switch between multiple forums and sometimes forget the background to a particular post.

In any case, I think my feedback still stands and is intended to help. If you disagree with the feedback, then let me know. Otherwise I think a full range measurement, compared to what you expected to be going on with your bass alignment (modeled vs measured) may enlighten us.

 

[YSDR]

Hi Rick!
How do you rate the ND25FW tweeter to the DXT subjectively? I asking because I used the Dayton but didn't heard the Seas yet.

 

[RickS]

Hi Rick!
How do you rate the ND25FW tweeter to the DXT subjectively? I asking because I used the Dayton but didn't heard the Seas yet.

Really have not had a lot of time to critically listen to it. So far, still seems a good value and have not heard anything that was significantly objectionable. Even with the C-Note’s woofer distortion creeping in, Amir liked it enough. Will reserve final judgment for when I have a more complete speaker to evaluate.

 

[Ktacos]

PE has the sig180 in the M6 speaker listed at 35hz, which seems a little low for sealed, can't imagine it gets very loud.

 

[Dave Bullet]

There's a recent test here that may back up your findings or be a good cross check for a possible faulty batch

Test Bench: The SIG180-4 6.5” Woofer from Dayton Audio’s Signature Series

Dayton Audio’s SIG180-4 is part of a woofer series with five cost-effective, high-performance models, ranging from 4” to 10”. All drivers include single-piece concave aluminum cones, polyimide vented voice coil formers, open cast-aluminum frames, plus indexed shallow transition NBR surrounds...

audioxpress.com

 

[RickS]

There's a recent test here that may back up your findings or be a good cross check for a possible faulty batch

Test Bench: The SIG180-4 6.5” Woofer from Dayton Audio’s Signature Series

Dayton Audio’s SIG180-4 is part of a woofer series with five cost-effective, high-performance models, ranging from 4” to 10”. All drivers include single-piece concave aluminum cones, polyimide vented voice coil formers, open cast-aluminum frames, plus indexed shallow transition NBR surrounds...

audioxpress.com

Thanks, I get Voice Coil so saw this review back when it released. Am still working through this with PE.

 

[RickS]

A brief update as have had some more dialog with PE on the SIG180. The ask was that I burn-in the driver for 24 hours at 50 Hz at 3/4 of Xmax. After that exercise, I was able to get Fs down to around 45 Hz. PE was happy and stated they have a 15% tolerance and now my driver met spec. But after letting the driver cool down overnight, Fs popped right back up to 48 Hz.

At this point, I pulled a new Wavecor WF182 from shelf stock and it measured a bit higher than spec, but at 35 Hz. So is much lower than the SIG180 Fs. I noted Wavecor wanted a break-in of 20 Hz for 2 hours at 10V. Since I was set up to do, thought I would try on the SIG180. After that the SIG 180 Fs was around 31 Hz. Thought for sure it was burned-in! Alas, after a few hours, it returned to 48 Hz. I have reported to PE and they are testing a new SIG180. On their DATS, the out-of-box Fs was slightly higher than mine. Am now awaiting for their burn-in results.

While I certainly understand that ambient conditions matter, my finding in this case, is that the claimed need to burn-in is only partially valid. Might argue that the ambient conditions matter more, but as they are fairly consistent in my case, my takeaway is that the burn-in has plateaued. At 48 Hz, would still be out of spec and makes it much less appealing than the initial look.

 

[Dave Bullet]

Are you worried about production consistency? Or more that it doesn't meet published T/S specs? Have you taken a look at distortion performance? I remember reading somewhere it was worse in the midrange than the reference range. I'll try and recall the detail

 

[RickS]

Are you worried about production consistency?

Concerned, but is more for PE to consider.

Or more that it doesn't meet published T/S specs?

Yes, but understand tolerances and may just go with the Wavecor to get the bass extension I originally targeted.

Have you taken a look at distortion performance?

Yes, it looks like the known profile shown in the Dickason review. Not great, but not bad for the money.

This thread is for the application of a woofer in the Denotiva speaker. If it helps others with their application, it is a side benefit. Rather not bog down the thread with a bunch of SIG180-specific banter.