Need help interpreting measurements

[montana1]

Hi Lojzek,
I have attached zip file of Xsim dxo file as you requested. Hopefully, you are able to unzip file with no difficulty. I had to really compress file to not exceed servers maximum file size. Thanks so very much for taking a look to see if the design can be simplified.


Best Regards,
Rich

 

[jReave]

Hi Rich,

Well, it more or less works but I think I'm with Lojzek - it could probably be simpler.

I guess 1st, considering your small room and starting with the full 6dB of bsc, I would make sure the level above about 1000Hz isn't sitting below the level below 1000Hz. Or in other words, I'm afraid that the balance in room might be just a tad heavy on the bass.

Also I'm trying to understand why you've decided to switch from 3rd order electrical with an added resistor and a tanking capacitor on the woofer to 1st order with 2 notch filters? That's a mite unconventional. But as I said, it does work.

But I still think that unless phase alignment just won't work, 2nd order electrical probably with a shunt resistor again to shape the knee and manipulate phase as well as the tanking capacitor aimed at about 3500Hz with a series resistor to modulate depth should do the trick. Less expensively too.

 

[Lojzek]

Thanks Rich, the will was there but the machine just wouldn't unzip it. I'll use the far field measurements of the drivers without near field and vent response that you posted already.

 

[montana1]

Hi jReave,
TBH, I have tried so many different combinations that maybe I have lost sight of just keeping things simple. If memory serves me correctly, I was having trouble with phase alignment with all 3rd order electrical combinations on the woofer but 3rd order electrical on tweeter works great. I'm going to attach another try at this with regards to simplifying things as you and Lojzek have pointed out. With this version I tried the resistor plus capacitor tank on L1 but found the notch filter method seemed to worked a little better. Also, I included system z with and without impedance compensation filter before tweeter. I tried it after the Xover and it does nothing for lowering the impedance hump. With regards to balance, I may have to aim for a flatter response after reading your comments about maybe the system being bass heavy with full bsc in a small room. But, that is something I can tweak before purchasing any components if you and Lojzek think I'm on the right track.

Thanks once again,
Rich

 

[montana1]

Hello Guys,
And another version to consider. What can I say it is snowing in north Idaho today. So, plenty of time to work on this design. This attempt is taking into account jReave's thoughts on a flatter response. Hopefully, there is no law against 3rd order electrical on both woofer and tweeter. I might have tried every conceivable combination known to man in an attempt to achieve a flat response and a 1.7k Xover point. What do you guys think?

Best Regards,
Rich

 

[montana1]

Hello Guys,
This attachment is the same design as from last post but values transferred over to PCD7.


Best,
Rich

 

[Lojzek]

Rich, would you try this one?


LP: 2.2 mH; 8.2 uF; 2nd order electrical
HP: 5.6 uF; 0.33 mH; 15 uF; 2.7 R; 3rd order electrical, resistor after HP

 

[montana1]

Hi Lojzek,
Here is attachments of design based on the values you provided.

Thanks very much,
Rich

 

[montana1]

Hi Lojzek,
What do you think of this version? I just added tank to L1 and changed C1 to 11uf in an attempt to align phase a little better. What would be nice about these designs is I have most all of the components already.


Thanks,
Rich

 

[Lojzek]

That looks to me as a solid iteration of a filter that will bring you closer to your goal. If you already have the parts, all the better. Have fun, and later you can mod it further, if necessary.

 

[montana1]

Thanks Lojzek,
I appreciate that you took the time to work on this with me. I will place an order on the few parts that are needed to build this Xover.

Best Regards,
Rich

 

[Lojzek]

You are welcome, in case that this ends up not so well, send me the bill, lol.

 

[AllenB]

I agree with Lojzek. Once you implement it you'll run across all the issues your simulation isn't showing, so one has to put a limit on obsessing at each stage of the game.

 

[montana1]

Hi AllenB,
I figure there was a point at this stage of diminishing returns. I just finished working up my Parts Express order. Its time to get this design built and test it out.

Best,
Rich

 

[montana1]

Lojzek,
Thanks once again. I'm sure it is going to work out extremely well! I'm not sure how many more speakers I will build. So, to keep this fun hobby going I will keep adjusting the Xovers in the speakers I already have to achieve the sound I'm looking for. On second thought, I may build a subwoofer next winter.

Best Regards,
Rich

 

[montana1]

Hi To All,
I just completed the xovers for the stand mount 2 ways featured in this thread. Attached below is the measurement of the speakers with xovers in place. I also included the simulated design from Xsim for comparison.
Photo 1: measured at 26 inches
Photo 2: measured at 6 feet
Photo 3: Xsim

As can be seen from photo 2, the small room is certainly wrecking havoc on the smoothness of the frequency response.


Best Regards,
Rich

 

[Lojzek]

Ok, and how does it sound now that it's all in place? Were the expectations met?

 

[giralfino]

The photo 2 only shows that the gate was too long for your setup and the measure picked up also a reflection. In a bigger room you probably would have had the same effect.

Ralf

 

[montana1]

Hi Lojzek,
The speakers sound pretty good. Maybe just a touch shy in the bass region. I may have to add a sub woofer to improve the balance of the system. Or it could be I'm looking for a project for next winter. The mid range and highs are excellent (no complaints there). Overall I'm extremely pleased how the project has turned out. Thanks so much for your help in designing the xover!

Best,
Rich

 

[montana1]

giralfino,
That is a good point. It was sure an eye opener for someone new to measurements how your sims can look so nice but soon as real world situations are in play it looks awful. But, I would think that is why so much is mentioned about room treatment on this forum.

Best,
Rich