Godzilla said:
I can't wait to hear them, but since I plan to do this one right, I will have to put on a proper finish followed by mounting the driver etc. At earliest probably in 2 wks due to my regular full time job. (at times like this I wish I was unemployed...)
I have been told by a reliable source, a tweeter from partsexpress
http://www.partsexpress.com/pe/psho...FTOKEN=83033797
will work well with 4uf capacitor on + side of the tweeter, that will result in crossing at 5KHz. when used with the Pioneer. No other crossover needed.
Is it right that crossover is not needed?
thanks,
gychang
>>> 4uf capacitor on + side of the tweeter, that will result in crossing at 5KHz. when used with the Pioneer. No other crossover needed.
>>> Is it right that crossover is not needed?
This is the technique used by most every fullranger (builders/hobbyists whatever you want to call us) out there. We let the main driver run all out without crossover. All you are doing is adding a helper tweeter. I do the same thing with the B20 and the piezo tweeter but I use a different value cap (and resistor). The tweeter you reference does not require the resistor. So a single capacitor (of desired value) would basically roll into the response of the B20 at a mild 6db per octave. You are essentially blending the two drivers together rather than choosing a crossover point and building a crossover for both drivers to meet at that point.
I think you should try a few other capacitors with different values to make sure 4uf is ideal. It may be perfect or it may require a bit of tweaking.
How are you thinking of mounting the tweeter? Front? Back?
Godzilla
>>> Is it right that crossover is not needed?
This is the technique used by most every fullranger (builders/hobbyists whatever you want to call us) out there. We let the main driver run all out without crossover. All you are doing is adding a helper tweeter. I do the same thing with the B20 and the piezo tweeter but I use a different value cap (and resistor). The tweeter you reference does not require the resistor. So a single capacitor (of desired value) would basically roll into the response of the B20 at a mild 6db per octave. You are essentially blending the two drivers together rather than choosing a crossover point and building a crossover for both drivers to meet at that point.
I think you should try a few other capacitors with different values to make sure 4uf is ideal. It may be perfect or it may require a bit of tweaking.
How are you thinking of mounting the tweeter? Front? Back?
Godzilla
Also, a little trick is to wire the tweeter in reverse of the woofer, puts it out of phase and gives a smoother response when running with a full range driver. You may want to also check out:
http://www.partsexpress.com/pe/showdetl.cfm?&Partnumber=275-070
Very smooth response. Currently using this in my BIB's using the Pioneer 4.5" fullrange, same as your other BIB's. I love this set, great for music, theater, you name it.
http://www.partsexpress.com/pe/showdetl.cfm?&Partnumber=275-070
Very smooth response. Currently using this in my BIB's using the Pioneer 4.5" fullrange, same as your other BIB's. I love this set, great for music, theater, you name it.
zayne742 said:
Sorry if off topic ... please move if required.
I've looked at the 4.5" Pioneer fullrange a couple of times. What BIB cabinet dimensions did you use? The specs are similar to the FE103 if I recall correctly.
Cheers,
Ryan
This was dervived from GM's formula.
Fs 70
Vas 0.31
Qts 0.35
Line Length 96.175
Folded Height 48.088
Vb 1.669
Sm 59.977
Depth 9.210
Width 6.512
zdriver 20.870
a-b-c 4.605
Pretty much the size mine are, Gychang's were:
"El Cheapo speaker BIB demension: (Scottmoose)
Try a 120in line length, driver at 24in down from the sealed end, 70in^2 terminus area. Inside demensions: 7x10, height:60, speaker placement: 24” from top to middle of the speaker, inside slanting baffle ends 5” from the floor and 5” from front and 5” from back."
Mine sound great, not sure if there is much benefit from the taller, with a bigger terminus.
Fs 70
Vas 0.31
Qts 0.35
Line Length 96.175
Folded Height 48.088
Vb 1.669
Sm 59.977
Depth 9.210
Width 6.512
zdriver 20.870
a-b-c 4.605
Pretty much the size mine are, Gychang's were:
"El Cheapo speaker BIB demension: (Scottmoose)
Try a 120in line length, driver at 24in down from the sealed end, 70in^2 terminus area. Inside demensions: 7x10, height:60, speaker placement: 24” from top to middle of the speaker, inside slanting baffle ends 5” from the floor and 5” from front and 5” from back."
Mine sound great, not sure if there is much benefit from the taller, with a bigger terminus.
The taller version is tuned lower, though I'm not sure about the larger mouth. Generally, following GM's formula the mouth will shrink, marginally, the lower you tune a BiB. I think Scott custom calc'd that one for gychang and it was pretty early on, too, so he may have had different goals in mind at the time.
Scott?
Kensai
Scott?
Kensai
http://www.zaphaudio.com/tweetermishmash/
gychang... have a look at the link above.
Any tweeter will work. Its a matter of choosing one and then going about optimizing the performance with the B20. Every tweeter will add its own flavor. Just dont get a spitty bright sounding tweeter... unless you like that kind of sound.
I also like the piezos out there with the B20. Pick a piezo, any piezo. But i understand many simply dont like the way they sound. When using the piezo you are really just extending the response of the B20 and not so much changing the B20s overall sound because the crossover is really high - 20k or so and blending back into the B20s response. But using one of the other tweeters and a much lower crossover point will change the sound. There is no right or wrong only different options to try and enjoy.
No matter what you do with the B20 it will never be state of the art sound. I like to keep it simple with this driver and love how easy it is to get very good sound from it thats very relaxing to listen to for long periods without fatigue. The B20 has been my office system for close to two years now and i always enjoy their sound thruought the entire day.
Godzilla
gychang... have a look at the link above.
Any tweeter will work. Its a matter of choosing one and then going about optimizing the performance with the B20. Every tweeter will add its own flavor. Just dont get a spitty bright sounding tweeter... unless you like that kind of sound.
I also like the piezos out there with the B20. Pick a piezo, any piezo. But i understand many simply dont like the way they sound. When using the piezo you are really just extending the response of the B20 and not so much changing the B20s overall sound because the crossover is really high - 20k or so and blending back into the B20s response. But using one of the other tweeters and a much lower crossover point will change the sound. There is no right or wrong only different options to try and enjoy.
No matter what you do with the B20 it will never be state of the art sound. I like to keep it simple with this driver and love how easy it is to get very good sound from it thats very relaxing to listen to for long periods without fatigue. The B20 has been my office system for close to two years now and i always enjoy their sound thruought the entire day.
Godzilla
I finished the BIB cabinets for my Pioneer B0FU . I still need to cut the driver openings and to do that I need to find my circle jig for the router...
Also need to add the damping..
IT will be 2 weeks before they are finished for a report as they are at a friends, and he has no time to work on them this week.
The guy I know who likes these drivers uses a cheap car audio dome crossed with a 1 mF cap. (EDIT: I meant 1 uF)
The tweeter decisions are the same for me of course....
Also need to add the damping..
IT will be 2 weeks before they are finished for a report as they are at a friends, and he has no time to work on them this week.
The guy I know who likes these drivers uses a cheap car audio dome crossed with a 1 mF cap. (EDIT: I meant 1 uF)
The tweeter decisions are the same for me of course....
gychang said:
Do not see why not. Mine are crossed @ 2.5k with a 8uf and a 0.5mh at 12db. Using a 4uf would cross them over at 5k @ 6db. They are extremely smooth for my setup. Not sure how they will work with the 8", but many others have used them with high satisfaction. I have been thinking about crossing mine a bit higher, so 5k may be a very good start. Good luck, and keep posting!
May have to start a new thread soon, when my next project goes under way. Not to go off topic, but here is a pick of the driver.
Attachments
Great looking work! Nice to see the pioneer put to good use.
As for "helper" tweeters, don't pass up this little Neo Dome from Part Express. I use them and like them. Works well when crossed up high.
The same basic tweeter comes in 2 flange styles. Sure is easy to place just about anywhere. And under $5 !!
Part numbers:
275-035
275-030
As for "helper" tweeters, don't pass up this little Neo Dome from Part Express. I use them and like them. Works well when crossed up high.
The same basic tweeter comes in 2 flange styles. Sure is easy to place just about anywhere. And under $5 !!
Part numbers:
275-035
275-030
panomaniac said:
Small enuff to stick it on the end of a cylindrical phase plugs to make a coax.
An externally hosted image should be here but it was not working when we last tested it.
dave
panomaniac said:
planet10 said:
Panomaniac: my kind of tweeter to try, should I use it with 4uf capacitor?, will that be high enough?
planet10: I have difficulty seeing how it would just "stick on the end of phase plug"....
gychang
Looking good GY.
I wish I could get nice plywood easily here.
I'm on hols now gonna build the Curvy Chang so we'll compare notes when I get back.
Just a quick thought, it would be possible to use biscuit joints to add a curved front to a standard Chang!
I wish I could get nice plywood easily here.
I'm on hols now gonna build the Curvy Chang so we'll compare notes when I get back.
Just a quick thought, it would be possible to use biscuit joints to add a curved front to a standard Chang!
marce said:
Great idea, yes indeed, I may add curves in front and toward rear as your design. I don't have biscuit cutter, but I do have a router that can do the job. Eventually I may add a tweeter.
gychang
That tweeter is so small you can just pop it into place at 11 oclock on one speaker and one oclock on the other. Small enough many may barely notice it. Looks like a good choice cosmetically for the curvy chang as well as any other BIB or double horn that needs a forward firing helper tweeter.
Thanks for the suggestion!
Godzilla
Thanks for the suggestion!
Godzilla
gychang said:
That shoud be a good starting point. It will give you a first order of about 6.5KHz. I have used these tweeters with as small as a 1uF cap. Because of the slow 1st order roll-off there is still plenty of sizzle coming out.
You may want to pick up few small caps and experiment with them in parallel. 1,2,3,4uF etc. A collection of small, cheap films caps can be your friend. I often get them in lots off eBay.
It's a fun little tweeter and as Dave and Godzilla say, it's small enough to stick anywhere and not get in the way. Heck, I may pop one in front of my Hemp FR8s. (Not that they need it). 🙂
panomaniac said:
panomaniac, can I pick few from this page?
http://www.partsexpress.com/solen-metallized-polypropylene-capacitors.cfm
thanks,
gychang
Yes, you can get few Solen, or try the Dayton at a slightly lower price.
Sometimes you will find mixed bags of film caps on eBay. It's a great way to experiment - having a lot of different values.
Look for an email from me about some caps on eBay.
Sometimes you will find mixed bags of film caps on eBay. It's a great way to experiment - having a lot of different values.
Look for an email from me about some caps on eBay.
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