TangBand W3871S...how to add tweeter and Xover

Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
I recently purchased a pair of TangBand W3871S drivers and put them in the same sized cabinets used by creativesound.ca. I was impressed by their handling and range but honestly I am left wanting for that upper frequency detail found in a two way. I know I know, it's a lot to expect a full range speaker to have the qualities and characteristics of a two way but I was expecting them sounnd better than they do. I am convinced that if coupled with a tweeter and Xover they would sound so much better. Also was wanting to know a good simple notch filter for these to filter out anything below say...110hz. So if anyone has any experience with these drivers and what I am describing...your advice and input would be greatly appreciated. Again I am looking for input on what tweeter to pair these with and a design for a crossover. Thanks in advance.
 
I was also looking at making a high-pass filter for the W3-871S at about 150Hz, but the components needed have really high values. So I would have to either:
- use a crappy capacitor
- pay over 50 Euro's for each speaker in components!

Isn't there a cheaper way to construct a highpass crossover at low frequencies? :D
 
Greetings Tang Band owners,

What did you plan to use on the bottom end? If you roll off the W3 at 150 or so, what will you use below that frequency? Because the W3 is has a second order slope in a sealed cabinet below resonance, adding a first order crossover produces a third order acoustic slope. To match on the low end, you need at least a third order low pass filter. It is this third order low pass filter that costs lots of money. When you consider the cost of large inductors, bi-amping becomes cost effective. Then with two amps, a simple passive first order 150 high pass will only cost a euro or so. At the prices for sub woofer "plate" amps these days, you can buy one for the cost of the two air core inductors and the one large capacitor required for the speaker level low pass filter.

I agree with Sound Quest that the high frequency qualities of the W3-871S could be better. The problem, however, is not extension. The transient onset response of the 871S is as good as every affordable tweeter (and all of those tweeters cost more than the 871S).

The problem is a nasty cone breakup mode centered around 17 kHz that is not documented in any of the posted response graphs I have seen. If you know what you are looking for you can see it in the response plots, it just looks so much smaller in magnitude than it actually is. It not only destroys the reproduction of overtone structure, it will play havoc trying to cross it over to a tweeter. It is too narrow and too high of a Q to notch it, and if you cross over so low that it becomes masked in the roll-off, why bother with a 3 inch driver at all?

I wish I had a solution as easy for the 871S high frequency sound as bi-amping is for the low frequency cross.

Best wishes with bi-amping,

Mark
 
I agree with Sound Quest that the high frequency qualities of the W3-871S could be better. The problem, however, is not extension. The transient onset response of the 871S is as good as every affordable tweeter (and all of those tweeters cost more than the 871S).
As much as I enjoy the W3-871S, alas, it's not perfect. The appeal is that you get a surprising amount of performance from a small, inexpensive driver. A better executed 3" full-range design is the Fostex FF-85K, but of course it costs 2x-3x as much. Have fun with the TB but don't set your expectations too high.
 
MarkMcK said:
Greetings Tang Band owners,

What did you plan to use on the bottom end? If you roll off the W3 at 150 or so, what will you use below that frequency? Because the W3 is has a second order slope in a sealed cabinet below resonance, adding a first order crossover produces a third order acoustic slope. To match on the low end, you need at least a third order low pass filter. It is this third order low pass filter that costs lots of money. When you consider the cost of large inductors, bi-amping becomes cost effective. Then with two amps, a simple passive first order 150 high pass will only cost a euro or so. At the prices for sub woofer "plate" amps these days, you can buy one for the cost of the two air core inductors and the one large capacitor required for the speaker level low pass filter.

I agree with Sound Quest that the high frequency qualities of the W3-871S could be better. The problem, however, is not extension. The transient onset response of the 871S is as good as every affordable tweeter (and all of those tweeters cost more than the 871S).

The problem is a nasty cone breakup mode centered around 17 kHz that is not documented in any of the posted response graphs I have seen. If you know what you are looking for you can see it in the response plots, it just looks so much smaller in magnitude than it actually is. It not only destroys the reproduction of overtone structure, it will play havoc trying to cross it over to a tweeter. It is too narrow and too high of a Q to notch it, and if you cross over so low that it becomes masked in the roll-off, why bother with a 3 inch driver at all?

I wish I had a solution as easy for the 871S high frequency sound as bi-amping is for the low frequency cross.

Best wishes with bi-amping,

Mark


An externally hosted image should be here but it was not working when we last tested it.

As far as the 17k spike' I think you missed these tests I did.
http://quicksitebuilder.cnet.com/wrnch2/diyspeakerbuilding/id1.html
All were done in the same cabinet same tuning same poly .
I think you will see these are also un smoothed as well

Al
 
kan3 said:
with a proper notch the peak can be squashed to 4-5db

it costs $17 shipped to your door....what were your expectations?


I wouldn't say my expectations were necessarily high for the 3", but I would say they were at least that of the myriad reviews I read on the W3871 before I purchased them. Still a pretty amazing 3" for the price despite its lack of detail in the uppermost frequencies (what my ears are used to). Since no one seems to think adding a tweeter will fix the problem I think I will leave it alone for now. However, I am convinced a notch filter (reccomended by many using the W3871) would bring some sonic improvement and smoothness to the driver at higher volumes. Anyone have a design? I am not literate (yet) when it comes to Electrical Engineering so if you could just spell out the parts instead just posting a schmatic that would be appreciated. Thanks.
 
SoundQuest said:



I wouldn't say my expectations were necessarily high for the 3", but I would say they were at least that of the myriad reviews I read on the W3871 before I purchased them. Still a pretty amazing 3" for the price despite its lack of detail in the uppermost frequencies (what my ears are used to). Since no one seems to think adding a tweeter will fix the problem I think I will leave it alone for now. However, I am convinced a notch filter (reccomended by many using the W3871) would bring some sonic improvement and smoothness to the driver at higher volumes. Anyone have a design? I am not literate (yet) when it comes to Electrical Engineering so if you could just spell out the parts instead just posting a schmatic that would be appreciated. Thanks.

I don't know that a tweeter wouldn't help, I'm just getting hung up on using the 871 as you're proposing. Did you see the other thread about the 3-way TB? There's a link to another site where someone built a 3-way using 2-8" woofs, the 4" as the mid and the little TB fabric dome tweeter.
 
SoundQuest said:
Does anyone know what parts to order from MCM to build John's notch filter for the W3871S found on his website at:
http://home.new.rr.com/zaph/audio/audio-speaker11.html

Also, I don't know how to read schematics so I get tripped up with John's instruction on how to build the filter exactly so anyone with insight here would be greatly appreciated. Thanks.

As far as I am concerned, the hardest part to find for me was the toroid. After contacting Jonh - good luck in finding his email address ;) - he told me it was readily available at Madisound. I'll order them as soon as I can finish working working on a non-DIY project of mine. :xeye:

BTW, I have already built both the small and the tall version of the enclosures that can be found about half way down the page. I am presently playing them fullrange without the notch filter in order to break the drivers in. Their sound is quite pleasing already. I'm eager to see what the effect of the filter will be.
 
Looking at the picture and description.

6.8 ohm non-inductive resistor (probably Mills)
3.3 mF metalized Polypropolene cap (maybe Hovland MusiCap)
.7 mH air core inductor

They're all wired in parallel, kinda side by side as it were and put in line with the wire leading from the input terminal to the positive terminal on the driver.
 
Timn8ter said:
Looking at the picture and description.

6.8 ohm non-inductive resistor (probably Mills)
3.3 mF metalized Polypropolene cap (maybe Hovland MusiCap)
.7 mH air core inductor

They're all wired in parallel, kinda side by side as it were and put in line with the wire leading from the input terminal to the positive terminal on the driver.


Thank you, so the notch doesn't "touch" the negative terminal?

A question for TB W3871S:
Is it possible to add a 150 CAP (Electrolytic capacitor) doing a high-pass filter (150Hz)? Should I add a 6-7 ohm resistor in series?
 
matos81 said:

Thank you, so the notch doesn't "touch" the negative terminal?

A question for TB W3871S:
Is it possible to add a 150 CAP (Electrolytic capacitor) doing a high-pass filter (150Hz)? Should I add a 6-7 ohm resistor in series?

Hi,

A) is true.

B) Yes it is possible. Though a series resistor is not a good idea.
A ~ 15R resistor to ground after the capacitor is a good idea.

:)/sreten.
 
Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.