Vifa p17 D25 by John K

[gehlhoff]

I built these about 8 years ago, now I can't find the crossover schematic anywhere does anyone have a link that still works?

[Dave Bullet]

Is this the one by John Krutke, John Krekovsky or another John K?

John Krutke frequents htguide and the partsexpress forums, so depending on what you want to do, he might help you (ie. you are replacing some electrolytics and need to know values etc...)

If you want to improve the sound - get a design with a better woofer. I would guess any of John K's (Zaph's) current designs would better it by a good margin.

Cheers,
David.

[tktran303]

Here you go:

http://web.archive.org/web/200310210...00_johnk.shtml

I'm not sure whether John would recommend this design with current drivers. Natural drift/driver variation/hindsight 20/20 etc.

I also have a XO design by Dennis Murphy from about 5 years ago...

And yes John Krutke also did a design and study/experiment a few years ago investigating the P17, IIRC collected about half a dozen designs from other designers, modelled the XO/box designs and with the mild to wild variations in end acoustic response concluded that this driver (which has been around since the beginning of time) is best when one can take their own measurements and design their own crossovers...

regards,
Thanh.

[gehlhoff]

I think it was John Krekovsky. I do remember it was a fourth order cross over. I wanted to model it up to try lpscad6 lite, but can't remember what is there already.

I had bought some replacement tweeters now that the kids are old enough not to destroy them. After reading up for the last couple weeks, I'm tempted to make something else with them.

[critofur]

Originally posted by Dave Bullet
Is this the one by John Krutke, John Krekovsky or another John K?

John Krutke frequents htguide and the partsexpress forums, so depending on what you want to do, he might help you (ie. you are replacing some electrolytics and need to know values etc...)

If you want to improve the sound - get a design with a better woofer. I would guess any of John K's (Zaph's) current designs would better it by a good margin.

Cheers,
David.

Hmm ~ I think what speakers sound good to somebody must be very much a matter of personal taste - that is, until we reach the day where somebody builds speakers that can actually accurately reproduce music, but we are far far from that day, and I don't think they will involve electromagnetic motors driving cones - that technology simply isn't capable of generating speakers that could achieve that. So, while I might agree that Zaph's designs could mostly sound better than say, B&W 801, etc. commercial speakers, there are various older (and sometimes very cheap) speakers that I have found more pleasurable to listen to than the few Zaph designs I've heard. Have you personally compared side-by-side some of Zaph's speakers to a Vifa P17 speaker?

Hehe, I finished a pair of Zaph's BAMTMs a while ago, they measure nice and flat, and they sound OK (better than most commercial speakers), but, I'm hoping to make something (perhaps futilely) that sounds much better with a Vifa P17 and D27TG-35 tweeter.

Here is my thread: Vifa P17WJ + D27TG-35-06 TL (non MTM)?

If that doesn't work out to sound great (probably won't, I think most speakers suck) then on to some other new design...

All that being said, I would still like to hear all of Zaph's recent designs, and I do think it's a safe bet to recommend any of them as a good speaker at a good value (or perhaps a great speaker, depending on your perspective).

[Dave Bullet]

Originally posted by critofur
[B]
So, while I might agree that Zaph's designs could mostly sound better than say, B&W 801, etc. commercial speakers, there are various older (and sometimes very cheap) speakers that I have found more pleasurable to listen to than the few Zaph designs I've heard. Have you personally compared side-by-side some of Zaph's speakers to a Vifa P17 speaker?

No I haven't. I'm just referring to comments made by Zaph in his archives where is says "Folks, avoid these drivers unless you have the ability to measure and model them yourself. And even then, the drivers are nothing special and there are better options out there"

gehlhoff,

I don't know faceplate dimensions of the D25, but I presume you want to recycle cabinets. If the D25s have a 104mm diameter faceplate, that opens up a whole lot of driver choices. The Seas Prestige series are very good - particularly the 27tbfc/g or 27tdfc and measure consistently, so you should be able to simulate a new crossover.

David.

[tktran303]

I'm hoping to make something (perhaps futilely) that sounds much better with a Vifa P17 and D27TG-35 tweeter.

A 6.5" MTM just plays 3dB louder than a 6.5" MT.

To make something that sounds in a different class/league to a P17/D27 (which I consider a plain vanilla 6.5" two way) I think you need to step up to something with faraday shorting rings, bigger woofers for lower extension, use dedicated midrange etc.

I've made 3x different 6.5-7" 2-ways (P17/D25, L18/27TBFCG, 18W/9500) and there are significant differences, but nothing I would call a day and night difference. Differences also depend largely on listening material and SPL.

What do you primarily listen to?

[critofur]

Originally posted by tktran303


A 6.5" MTM just plays 3dB louder than a 6.5" MT.

To make something that sounds in a different class/league to a P17/D27 (which I consider a plain vanilla 6.5" two way) I think you need to step up to something with faraday shorting rings, bigger woofers for lower extension, use dedicated midrange etc.

I've made 3x different 6.5-7" 2-ways (P17/D25, L18/27TBFCG, 18W/9500) and there are significant differences, but nothing I would call a day and night difference. Differences also depend largely on listening material and SPL.

What do you primarily listen to?

First of all, let me say: expensive speakers often sound worse than (good sounding) cheap speakers.

You didn't read my post right - I said "better WITH" not "better THAN". I want to use those drivers and hope to make a speaker I like. Not saying I'll suceed... And I don't want to make MTM because I have just one pair of P17s and I would want to hear them before I bother to buy another pair. I've heard various people enthuse about P17's excellent bass, and I want to try them in a TL.

Anyway, to answer your post:

For the most part, I don't listen to music much because speakers all sound like crap to me.

I like the volume on my Onkyo 787 reciever on "50" (63 is "reference level" -0 db). I'm not sure how many db that is, I should get an SPL meter I suppose. BTW, I'm not happy with my reciever for music, though it's simply awesome for home theater. I don't understand, because, I always thought the difference between solid state recievers that some people claim to hear was just BS. I thought, that so long as your reciever is not clipping, solid state is solid state, and any difference in sound would be something people are imagining (bias has a powerful affect) - like "high end cables", which, I'm still convinced are pure hogwash.

If I go to an audio boutique and try to listen to their "high end" speakers, most of them sound unpleasant and soon give me a headache. I did like the Madrigal Revel Salon Ultimas, they did very well, except for The Matrix soundtrack, which is odd, because they should have handled that very well?

I recently made a pair of Zaph's BAMTMs, about half of my CDs that I tried sound decent on those. Eric Clapton Unplugged and Paul Simon's Graceland both sounded good, Tool sounded OK, Pearl Jam (their most popular album, forget the title) didn't sound good, Sarah McLaughlan w/Building a Mystery sounded decent.

CDs/bands that I'd like to listen to, if I had speakers I found pleasant enough:

Tool
Supertramp - Even in the Quietest Moments
Joni Mitchell - Blue
Rickie Lee Jones
Fleetwood Mac - Rumors
Bach
YoYo Ma - Inspired by Bach
Marcy Playground
Beastie Boys - Check Your Head
Matchbox 20 songs: Real World and 3 AM
REM and Talking Heads (a few of their CDs I haven't listened to in more than 10 years, I'd dig them up if I had an awesome stero again)
That one song from the opera Carmen (Habanera? just that one song, I know if I like opera, generally) sung by Marie Bizet?
A couple songs from Clockwork Orange soundtrack
Led Zeppilen
Crosby, Stills, Nash, & Young


And, there are many assorted songs that I like where I might not want to hear the entire album, here are a few: Steppenwolf - "Magic Carpet Ride", Beatles - "I've Just Seen a Face", ? - "Little Green Bag, Ride of the Valkyires, Buffalo Springfield, various 60's, 70's, 80's, and 90's top 40 songs, etc.

Originally posted by Dave Bullet

gehlhoff,

I don't know faceplate dimensions of the D25, but I presume you want to recycle cabinets. If the D25s have a 104mm diameter faceplate, that opens up a whole lot of driver choices. The Seas Prestige series are very good - particularly the 27tbfc/g or 27tdfc and measure consistently, so you should be able to simulate a new crossover.

David.

Rabbitz, who seems to have worked a lot with Vifa drivers including the P17 and those various Vifa tweeters, mentioned that he likes the Seas 27TDFC a lot better than the Vifa tweeter, I think. Sorry I couldn't find his post where he said that, though.

[tktran303]

Hi Critifur,

I see your sentiment regarding speakers, amplifiers etc not sounding great with music.

Actually I made no statement (direct or implied) with regards to cost being a measure of quality. I am firm believeer that expensive doesn't mean better or more enjoyable.

I also find that with program material similar to what you listed often sounds best on run of the mill stereos, sometimes in a car or truck even.

If what you listen to is more enjoyable on "good sounding cheap speakers" then be glad you can enjoy what you enjoy, and spend money on other things you consider more worthwhile!

For me, hi-fidelity is like a big macro lens on a SLR camera. You see anything from close up, but sometimes its not desirable to see everything, warts and all...

regards,
Thanh.

[critofur]

Ah, maybe so, most of what I listed are bands that play through PA systems...

On the other hand, I once heard a speaker which, at least for one magical moment, brought Miles Davis' trumpet right there into the room with us. The only time any speaker, at any price, ever did that.

The YoYo Ma cello CD ~ I don't think that fits in with the "sort of music you listen to probably sounds best on good cheap speakers" category. For that, I want speakers that puts the cello THERE IN MY ROOM, I don't want to listen and say "I can still tell the music is coming from speakers".

I don't think a pair of speakers exists that can do that, at any price.

In fact, perhaps some music would sound best coming from ONE speaker, rather than a stero pair?

What I hope that I will achieve with a pair of Vifa P17 + Vifa D27 tweets is the fun to listen to, decently good pair of speakers that I've been missing for the last 15 years or so when I lost the cheap bookshelf speakers that my dad brought home as my birthday present from the stero store he used to own back in 1977 which were driven by a Dyna tube amp. Other than the $20K Revel Ultimas, every $5,000 - $25,000 speaker I've auditioned since then just hasn't sounded appealing...