DIY speaker

[nm2285]

I'm finishing up planning a speaker project and wanted to see if anyone had experience with these drivers:

Vifa XT25TG30-04 http://www.partsexpress.com/pe/pshowdetl.cfm?&PartNumber=264-555&DID=7

Peerless 850439 http://www.partsexpress.com/pe/pshowdetl.cfm?&PartNumber=297-638&DID=7


I was at one point considering the Vifa MG18WK09-08, but I think it would be an upgrade in going with the Peerless. I've also heard the Vifa DX25TG-05-04 ( http://www.partsexpress.com/pe/pshowdetl.cfm?&PartNumber=264-578&DID=7 )is an excellent performer and if it is close enough to the XT, the saved $50 would be very welcomed. Looking forward to feedback!

 

[Rip Van Woofer]

I was looking at the Vifa XT25TG30-04 for my next project, too. So I second that question! And the other Vifa tweeter you mentioned, for that matter.

Is there a site out there where some speaker building fanatic has measured these drivers? One Audioholic once mentioned that he did some tweeter measurements including Raven ribbons and had them posted on his site but I didn't bookmark it.

I can tell you that my current Linkwitz DIY speakers use the Vifa D26TG-35-06 tweet ($25.90 at Parts Express) and they sound very nice. They were spec'd by Linkwitz. A quick and dirty in-room pink noise test (on-axis only) showed smooth response from the ~25kHz crossover point on up.

But there's always something better, eh?

 

[jeffsg4mac]

Certainly nothing wrong with VIFA tweeters, I have built at least a dozen speakers with them and they always sounded great.

 

[nm2285]

Certainly nothing wrong with VIFA tweeters, I have built at least a dozen speakers with them and they always sounded great.

Ever used either of the two we're discussing here?



Rip-
I posted this in another forum as well and someone gave me this reply:

"I've been a bit underwhelmed with the performance of the dx25. The xt25 is much better.

If you want to save money both the Seas 27TDFC and 27TDC are much better performers than the DX25 in this price range.

See my tests


http://my.starstream.net/mk/Webpages/ "

Have you considered which midrange(s) or woofers you are going to use?

 

[Rip Van Woofer]

Excellent link! Thanks! I hope he continues his tests. Got me thinking of using the XT19 tweet. That's a seriously flat on-axis response!

I'm using Vifa P21WO-20-08 8" woofers for the bass and mids per Linkwitz's specs so far. Though another builder has done the same design with Peerless units and reports good results (don't have the model # handy) so I might look into that. Crossover seems to be around 2.5kHz but I have to look closer at that.

Now for the "more than you want to know" section:

I'm building his suggested "budget" variation (or maybe a variation of his variation!) of his Phoenix open-baffle dipole design, the PMTM1 ("Prototype Mid-Tweeter-Mid One"). The Phoenix uses very expensive Scan-Speak drivers. I'm hoping for 90% as good at half the price!

I am planning on integrating a two-channel amp for biamping into the speaker stand using Elliott Sound PCBs and design - the 3A amp - and integrating it into the speaker stand. There's also a peak limiter circuit shown on the Elliott site that I might add to the tweeter amp since, as built, it will be around 100 watts/ch. The amp is a very compact design. Should fit on a long, skinny chassis oriented vertically in the back of a U-shaped stand. Got a nice heavy heatsink extrusion on eBay to keep it cool, fins will face the rear.

What the heck, here's a pencil sketch I did while sitting around the other night...

 

[nm2285]

Where'd you see the graphs for the XT19? I'm seeing a flatter response for the 25s in the manufacturer's specs.

 

[Rip Van Woofer]

Where'd you see the graphs for the XT19? I'm seeing a flatter response for the 25s in the manufacturer's specs.

On his Tweeter Test Group Three page. See also his conclusions.

 

[nm2285]

Well that was dumb: I completely missed that link. It does look pretty flat though. And, with better off axis performance, mine as well save the $10-12/pair.

 

[nm2285]

I did a bunch more calculations today and think I've finally decided on the project:

Vifa XT19
Peerless 850122 (CSC-X 176)

I like the idea of the XT19 over the XT25 because of the off axis response measured by the website in this thread. I was going to get the Peerless 850439 (HDS 182) until I read this on Madisound.com:
"The HDS line of woofers are similar to the CSC-X line, but with cast frames."

I'm going to implement a 4th order Linkwitz-Riley crossover at 2700 Hz. The Vifa begins to have consistant and significant distortion around 2.5 kHz while the Peerless has a significant increase in output beginning around 3 kHz. I'm hoping the steep crossover point in between these two problem areas will do well to minimize them.

Any opinions on this? Hope this may give you an idea or two, Rip (btw, thanks for pointing out the XT19 on that webpage!).

 

[nm2285]

BTW, Rip: The XT25 that's used in Polk LSi speakers is for sale on ebay right now (for $80 plus $12 shipping). It's new and has the Polk faceplate and all. Kind of a neat thing if you'd be interested at all. Plus it's about $15 off the normal price.

 

[Rip Van Woofer]

Been away for awhile; based on my limited knowledge your plans sound A-OK. I won't be building my next speakers for some time (months, at least) so I'll wait till then to shop tweeters. X19 is a real contender.

I think that's about where my current speakers are crossed over.

Only thing that gives me pause (and it applies to my current speakers, too) is crossing over an 8" driver at such a high frequency; off axis response of a driver that size "way up there" might be ragged. Compromises, compromises...!

BTW, I was just in Toronto & saw an exhibit of Art Deco furniture at the Royal Ontario Museum. Real inspirations for my next speakers except that I would need to acquire some serious cabinet making skills and tools to do them! Hmm...Maccassar Ebony inlaid with ivory and brass...yeah, I can do that...NOT!

 

[nm2285]

The Peerless are 6.5 inchers, not 8. I expect they should be fine crossed over at that point.

I have all the materials and have started building. Will let you know how they tunred out (especially the xt19).

Hope you enjoyed your vacation. Sounds like its time to work on those woodworking skills!

 

[Mudcat]

BTW, I was just in Toronto & saw an exhibit of Art Deco furniture at the Royal Ontario Museum. Real inspirations for my next speakers except that I would need to acquire some serious cabinet making skills and tools to do them! Hmm...Maccassar Ebony inlaid with ivory and brass...yeah, I can do that...NOT!

Rip,

How much wood do you use in your speaker cabinets? Just a veneer, or thicker than 1/4 inch?

 

[Rip Van Woofer]

Never done veneer or hardwoods. I'm not that good. I'm a MDF-and-a-gallon-of-woodfiller kind of guy. My current speakers are simply painted MDF. If I get ambitious and try real wood of any sort on my next speakers it'll probably take me forever. Hope the nursing home will let me bring them with me!

However, being a former theatrical scenic artist, signwriter, and son of a painting contractor, I am fairly good with paint and faux finishes. I've considered going that route. Pink Italian marble, anyone? Or perhaps tortoiseshell with gold leaf accents...

 

[nm2285]

Rip,

How much wood do you use in your speaker cabinets? Just a veneer, or thicker than 1/4 inch?

In my research, I've found it doesnt really matter all that much. Veneer it or 1/4inch it...whatever. As long as you're using 3/4 or 1 inch MDF under it, you'll be fine.

 

[Unregistered]

I would like to use vifa tweeter. but i wonder whether to choose Xt19 or XT25.. which 1 is better for car audio?

 

[nm2285]

With some of the measurements I've seen, I'd go for the XT19. It has better off axis performance (which is just about everything in a car). Plus, it'll save you a few dollars.

 

[Unregistered]

I see, thanks for the reply. How about any idea of the 4" mid?

 

[Unregistered]

how much power do u guys feed into this XT25 or 19? is 35w will b enough in an active system?