With a little luck you could get $20- for the Vifa tweeters in our "Trading Post" now unfortunately called swap meet, ask if any-one has a pair of the Neo tweeters for sale at the same time.
SpeakerBits in Melbourne still shows stock of these at AUD$ 39-each ( plus GST for Australian sales )
SpeakerBits in Melbourne still shows stock of these at AUD$ 39-each ( plus GST for Australian sales )
Bill check out the trading post? swar meet forum; this feller Bob may be able to help you; you will of course have to pick-up or pay for post and packing.
http://www.diyaudio.com/forums/showthread.php?s=&threadid=146066
Havagood1
http://www.diyaudio.com/forums/showthread.php?s=&threadid=146066
Havagood1
Stuey did you use a peak filter with those?
I personally think the little Neo tweeter is great, but it too has a fairly high Fs, but with a second order at 3k Bill should be OK with either.
I base this on the fact that his available power isn't great at about 30watts a channel and this being 3.5 way the tweeters will be getting about 5% of the total so should be safe even for ~150 watt peaks
I personally think the little Neo tweeter is great, but it too has a fairly high Fs, but with a second order at 3k Bill should be OK with either.
I base this on the fact that his available power isn't great at about 30watts a channel and this being 3.5 way the tweeters will be getting about 5% of the total so should be safe even for ~150 watt peaks
Ted, what's a peak filter? 
I should say here that you know a lot more about speaker building than me. Basically, I used a symmetrical 2nd order L-R crossed at 4K, with an L-pad on the tweet for efficiency matching and a Zobel on the woofer to flatten the impedance. I know my poly cone Peerless woofer is a bit stretched when asked to go this high, but still...
Thing is though, I didn't measure the FR as I had no means to do so, so it was all textbook stuff from Dickason's book plus some electronic measurement of impedance using DMM's etc. as described on various sites.
I must admit, though, that the result is pretty good considering.
I've just made a measurement mic and pre-amp and intend to re-do this project, though.
Stuey
I should say here that you know a lot more about speaker building than me. Basically, I used a symmetrical 2nd order L-R crossed at 4K, with an L-pad on the tweet for efficiency matching and a Zobel on the woofer to flatten the impedance. I know my poly cone Peerless woofer is a bit stretched when asked to go this high, but still...
Thing is though, I didn't measure the FR as I had no means to do so, so it was all textbook stuff from Dickason's book plus some electronic measurement of impedance using DMM's etc. as described on various sites.
I must admit, though, that the result is pretty good considering.
I've just made a measurement mic and pre-amp and intend to re-do this project, though.
Stuey
Peak filters are used to flatten the drivers response, see page 149 of the "Cookbook"
I've never built one BTW, as I try and avoid drivers that need them, buy it is easier to delete a peak that make an addition to allow for a drop in response, so "better a peak than a dip"
The FR pages from Vifa used to show the filter required with this particular tweeter, also showed the minimum XO slope and frequency.
I've never built one BTW, as I try and avoid drivers that need them, buy it is easier to delete a peak that make an addition to allow for a drop in response, so "better a peak than a dip"
The FR pages from Vifa used to show the filter required with this particular tweeter, also showed the minimum XO slope and frequency.
I have an older version of the Vifa spec sheet - one with graphs that look like they're done on an analogue tracer. Unfortunately mine only has a recommended crossover.
I do intend to completely redisign the crossover. I know quite a bit more now, and am more into this forum than I was back then.
I do intend to completely redisign the crossover. I know quite a bit more now, and am more into this forum than I was back then.
Bill, that sounds pretty small to me. Ted'll have more of an idea.
Ted, was your last response to me? I should just clarify that my mid-woofer was a low end Peerless - 813916 - which I've never found used in any project, which may say something! I went for it on a price/specs basis simply because it was my first ever speaker project, and I didn't want to end up wasting money. I didn't in the end, but if I had my time over again I'd build an established design first up, as regularly recommended on here.
Yes, I agree that the crossover should be lower. Some factors are in favour of a high crossover in respect of the tweet only, though.
Cheers
Stuey
Ted, was your last response to me? I should just clarify that my mid-woofer was a low end Peerless - 813916 - which I've never found used in any project, which may say something! I went for it on a price/specs basis simply because it was my first ever speaker project, and I didn't want to end up wasting money. I didn't in the end, but if I had my time over again I'd build an established design first up, as regularly recommended on here.
Yes, I agree that the crossover should be lower. Some factors are in favour of a high crossover in respect of the tweet only, though.
Cheers
Stuey
At what frequency?
Nominal 6R, but if you look at the graph page Stuey posted ( thanx Stuey) you will see the trace at the bottom, that is the impedance for that tweeter; scale on the right side; so select the XO frequency and run down the vertical until it crosses the trace and that is approximately the impedance at that frequency.
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