He used a basic XO calculator and adjusted values to be
standard from the shelves. We know from experience
that we achieve better results when we simulate the whole
thing. The first is Solen version, the second is baffle step
compensated made of 1,2 mH and 10uF. To achieve a
higher XO point, the filter should be modified.
standard from the shelves. We know from experience
that we achieve better results when we simulate the whole
thing. The first is Solen version, the second is baffle step
compensated made of 1,2 mH and 10uF. To achieve a
higher XO point, the filter should be modified.
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I don't know if the tweeter XO filter is correct. I do know that
in all this wild guessing when I use manufacturer's plots, I get
one response, whe I use Jeff's, then the response looks something
else. No tweeter padding. Have a look at this thread:
Airborne, RT-4001, Air Striction Tweeter - Techtalk Speaker Building, Audio, Video Discussion Forum
edit: correction of L value in post #22, should be 1,5 mH (0,5 dcr)
in all this wild guessing when I use manufacturer's plots, I get
one response, whe I use Jeff's, then the response looks something
else. No tweeter padding. Have a look at this thread:
Airborne, RT-4001, Air Striction Tweeter - Techtalk Speaker Building, Audio, Video Discussion Forum
edit: correction of L value in post #22, should be 1,5 mH (0,5 dcr)
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A very crude filter proposal for an easy experiment. I am not
sure how much RT 4001 distorts in the XO region, hopefully
not very much. I have assumed 15 mm of Z offset and the
response is on the tweeter axis. High frequency rise will probably
be down off-axis. The plot doesn't look great because of the inductor
you already have and there is no point in further making things
more complicated.
woofer: 1,5mH(0,5 dcr); 6,8 uF
tweeter: 1R; 15uF; 0,24 mH (0,25 dcr)
sure how much RT 4001 distorts in the XO region, hopefully
not very much. I have assumed 15 mm of Z offset and the
response is on the tweeter axis. High frequency rise will probably
be down off-axis. The plot doesn't look great because of the inductor
you already have and there is no point in further making things
more complicated.
woofer: 1,5mH(0,5 dcr); 6,8 uF
tweeter: 1R; 15uF; 0,24 mH (0,25 dcr)
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Thank-you for those measurements. Do you advocate "not" offsetting the tweeter as Graveson does? I was considering doing that.
And yes, I was considering lowering the shunt cap value if I were to use the 1.5mh coil I have. If you feel I shouldn't use it, I don't mind getting something else.
My primary concern is the tweeter Xover. I spoke with solen and he is so certain about this tweet -and nothing could beat it below $250- that he would take it back, no questions asked, if I was unhappy. That sort of impressed me.
I am buying the 104mm optional face plate for this tweet. It measures out nicely for a 4 inch hole saw which I need to buy, anyway. I would like the countersinks to look good. http://solen.ca/products/speakers/home-speakers/home-speakers-accessories/rt-4001fp/
And yes, I was considering lowering the shunt cap value if I were to use the 1.5mh coil I have. If you feel I shouldn't use it, I don't mind getting something else.
My primary concern is the tweeter Xover. I spoke with solen and he is so certain about this tweet -and nothing could beat it below $250- that he would take it back, no questions asked, if I was unhappy. That sort of impressed me.
I am buying the 104mm optional face plate for this tweet. It measures out nicely for a 4 inch hole saw which I need to buy, anyway. I would like the countersinks to look good. http://solen.ca/products/speakers/home-speakers/home-speakers-accessories/rt-4001fp/
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I wasn't thinking of offsetting tweeter. Will give you a slight improvement
probably. Can't judge its performance, but any guesswork design without
proper measurements isn't enough to make that kind of a decision.
My feeling about these is something along the lines of what Zaph thinks.
Zaph|Audio
I have owned once a magnetostat and that tweeter simply couldn't play
details that I hear all the time with normal dome tweeters. I was hearing
that on-axis too. Everything was good with FR and filter. Maybe I wasn't
lucky with my choice, but I won't be spending money on a ribbon tweeter
again.
If this seller gives you the opportunity to return the item if not satisfied,
that sounds fair to me.
The LP of the woofers is important too. Properly done can fill the frequency
hole. Reducing the LP inductor to 1 mH might just do that with a very little
midrange boost.
Check this thread and if you think you can execute the exact measurements
then I am positive that everything will be swell.
http://www.diyaudio.com/forums/mult...er-isodynamic-tweeter-2-way-build-thread.html
probably. Can't judge its performance, but any guesswork design without
proper measurements isn't enough to make that kind of a decision.
My feeling about these is something along the lines of what Zaph thinks.
Zaph|Audio
I have owned once a magnetostat and that tweeter simply couldn't play
details that I hear all the time with normal dome tweeters. I was hearing
that on-axis too. Everything was good with FR and filter. Maybe I wasn't
lucky with my choice, but I won't be spending money on a ribbon tweeter
again.
If this seller gives you the opportunity to return the item if not satisfied,
that sounds fair to me.
The LP of the woofers is important too. Properly done can fill the frequency
hole. Reducing the LP inductor to 1 mH might just do that with a very little
midrange boost.
Check this thread and if you think you can execute the exact measurements
then I am positive that everything will be swell.
http://www.diyaudio.com/forums/mult...er-isodynamic-tweeter-2-way-build-thread.html
I have a 1 mh coil but it's only 16 ga. I could order a 14.
I am not entirely "stuck" to the ribbon idea. I only know that I am not satisfied with the metal dome seas I have at present. If anything, I would probably go with the 27tffc. The FR looks good to me and it extends quite a ways beyond the metal dome I have. I could use the pre-existing crossover you helped me out with a while ago. I like it a lot. I just had a peek at the numbers of both tweets and they're almost exactly the same except the moving mass is lighter on the 27tffc. I would only need to lower the value of the resistor from 12 ohms to 10... or 8.
I will be making some sort of decision on Friday morning.
I am not entirely "stuck" to the ribbon idea. I only know that I am not satisfied with the metal dome seas I have at present. If anything, I would probably go with the 27tffc. The FR looks good to me and it extends quite a ways beyond the metal dome I have. I could use the pre-existing crossover you helped me out with a while ago. I like it a lot. I just had a peek at the numbers of both tweets and they're almost exactly the same except the moving mass is lighter on the 27tffc. I would only need to lower the value of the resistor from 12 ohms to 10... or 8.
I will be making some sort of decision on Friday morning.
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For example, this is a more expensive unit. I look at the response curve and where it starts to roll off. I wouldn't buy this thing.
http://solen.ca/wp-content/uploads/27tbcdgbdxt.pdf
compared to this:
http://www.troelsgravesen.dk/3WClassic_files/27TFFC.pdf
http://solen.ca/wp-content/uploads/27tbcdgbdxt.pdf
compared to this:
http://www.troelsgravesen.dk/3WClassic_files/27TFFC.pdf
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I dunno. You tell me, what would you get for 200 CDN each, at most? I'd like to keep it at 6 ohms so I don't have to spend a tonne on new caps. But, if I have to go with 8 ohms, I can add a bypass cap, change the resistor and lower the value of the coil if I have to. I already own the bass drivers and the boxes are 1/2 built.
Tweeters - Solen Electronique - World leading producer of high-end crossover components
Tweeters - Solen Electronique - World leading producer of high-end crossover components
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IMO 200 CAD is overpriced, although great companies like SB Satory,
SS, Seas, Morel etc. will be more than very good bearing in mind they
have the right sensitivity (90 dB ) and diameter you need for your box
opening. As a good catch I spotted SS D2904/9400SE. A 4 ohm unit
with high enough SPL and very good build quality.I wouldn't worry about
the expensive XO parts, they are never that important.What you do with
a filter is crucial and we know we're driving blindfolded.
http://solen.ca/products/speakers/home-speakers/tweeters/d29049400se/
SS, Seas, Morel etc. will be more than very good bearing in mind they
have the right sensitivity (90 dB ) and diameter you need for your box
opening. As a good catch I spotted SS D2904/9400SE. A 4 ohm unit
with high enough SPL and very good build quality.I wouldn't worry about
the expensive XO parts, they are never that important.What you do with
a filter is crucial and we know we're driving blindfolded.
http://solen.ca/products/speakers/home-speakers/tweeters/d29049400se/
The response looks pretty good. The mass of the dome is a little more than the Seas 27tffc but the SS seems a little smoother. The Fs is a "little" higher but still very reasonable.
But that's a good sale price on that tweet!
https://www.madisoundspeakerstore.c...s-prestige-27tffc-h0881-textile-dome-tweeter/
What modifications do you feel I would have to make to the crossover you helped me out with a while ago? In reference to the XO parts, I don't go above the Solen silver line. They're excellent.
But that's a good sale price on that tweet!
https://www.madisoundspeakerstore.c...s-prestige-27tffc-h0881-textile-dome-tweeter/
What modifications do you feel I would have to make to the crossover you helped me out with a while ago? In reference to the XO parts, I don't go above the Solen silver line. They're excellent.
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It's up to you. You can parallel the bass drivers, by all means, but the filter conversion is less straightforward.
I have certain theoretical reservations about parallel wired basses, but it's YOUR hobby.
Sounds a like a fun speaker you are building.
The Vifa PL14WJ link should give you some ideas. I don't suppose it's a wildly different 5" driver.
What are your theoretical reservations about parallel bass drivers? I hadn't heard of this! Feel free to get technical
What are your theoretical reservations about parallel bass drivers? I hadn't heard of this! Feel free to get technical
We mustn't get off-topic here, because this is Shane's build, but a little.
There are two theoretical problems with MTMs. Well, trade-offs really.
Firstly two basses and a single dome tweeter have different power falloff with distance. Cylindrical inverse distance versus spherical inverse square. The ribbon example above is better in this respect and projects the top end better. Or an MTTM might be another way to do this.
The second is my own notion that parallel wired basses can have a rocking motion in a common enclosure. Wired in series, they get the same current, so this can't happen.
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This is funny really. Rearrange the following into an MTM while keeping the same components. I don't think it can be done. The 2.5mH coil is too big. I don't want the 0.33mH either.
I found Troel's 1mH and 12uF Vifa circuit worked well.
Vifa PL14WJ-
I've used those values (Well, 1.8mH plus 6.8uF, because it converts) in an MT. Tweeter filter to taste. As near as I could get.
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Interestingly Steve, this crossover works really well! I have pulled the upper mid on the Audax woofer down by using 22uf as the shunt. Not hot on the midrange at all, no listener fatigue, at all! If there's one thing I hate, it's that.
But yes, I know, this was originally an MT xover and not an MTM
That's why I "was" considering using the 12ga 1.5mh I have on hand. I paid good money for them and it sucks to have them sitting in a cardboard box in the basement. However, if it simply refuses to work, I have a couple of 1mh tape coils but they're only 16ga. I could try your notch and see how that works too. It's not expensive.
I noticed you're using an 8 ohm visaton. Lojzek helped me out with this crossover solution for the tweet but it's a 6 ohm crossover. Aren't these 2 ohms difference imperative? I would think this changes the game, completely.
The 1 ohm resistor before the bass drivers... what is its purpose?
But yes, I know, this was originally an MT xover and not an MTM
That's why I "was" considering using the 12ga 1.5mh I have on hand. I paid good money for them and it sucks to have them sitting in a cardboard box in the basement. However, if it simply refuses to work, I have a couple of 1mh tape coils but they're only 16ga. I could try your notch and see how that works too. It's not expensive.
I noticed you're using an 8 ohm visaton. Lojzek helped me out with this crossover solution for the tweet but it's a 6 ohm crossover. Aren't these 2 ohms difference imperative? I would think this changes the game, completely.
The 1 ohm resistor before the bass drivers... what is its purpose?
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