Home » Sponsored » Pi Speakers » 4 pi, oh my! (pi 4)
4 pi, oh my! [message #66242] Mon, 21 February 2011 18:14 Go to next message
EL Jack is currently offline  EL Jack
Messages: 5
Registered: February 2011
Esquire
Just picked up a pair of assembled but unfinished pi4 speakers.

Haven't even begun a thorough "test" but I'm already knocked out by their absolute lack of compression. I'm also impressed with the treble response. Listening to the Heifetz Sibelius concerto on Classic reissue right now - wow.

Currently running on solid state (Arcam) but will get it on my Cary monoblocs soon, so I expect it to even sound better on tubes: which leads me to my question - are these a good load for tubes? (I have the Cary KT-88-based monos, which are 25 watts, switchable to 50 - but they don't have a 4-ohm tap).

My other question is with regard to the cabinet - the person who built them didn't make mirror-image pairs (that is, as I look at the speakers the ports are both on the right). Is this the intended design?

Okay, one more question: do folks put these on stands? I was thinking of 3 inches of maple block and 4 hockey pucks per side.

Again, wow and thanks for bringing this great speaker into the world~!

Re: 4 pi, oh my! [message #66243 is a reply to message #66242] Mon, 21 February 2011 19:07 Go to previous messageGo to next message
Wayne Parham is currently offline  Wayne Parham
Messages: 18167
Registered: January 2001
Illuminati (33rd Degree)

They're a very easy load for tube amps. High efficiency and benign impedance curve. Perfect for tubes.

They are intended to be built and used in mirror images. This is mostly for aesthetics but there is a very small oblique tilt in the position of the forward lobe and the upper and lower nulls. For that reason, I generally suggest the tweeters be outboard. That way the upper null is slightly to the outside and the lower null is slightly to the inside. But it's so slight, it really doesn't matter.

Stands are according to personal preference, but I generally like to suggest that stands be limited to small risers if subs aren't used. This helps reduce floor bounce by keeping the midwoofer/floor distance small. On the other hand, this speaker really works best when used with subs, and in that case, I like to use stands about 9-15 inches. This puts the center of the forward lobe right at listening height. The subs should be blended with the mains, which smoothes room modes, including floor bounce. More about that in the document below:

http://lonestaraudiofest.com/2009/Photos/PiSpeakers_10.jpg

http://lonestaraudiofest.com/2009/Photos/PiSpeakers_06.jpg

http://lonestaraudiofest.com/2009/Photos/PiSpeakers_02.jpg
Re: 4 pi, oh my! [message #66244 is a reply to message #66243] Mon, 21 February 2011 19:38 Go to previous messageGo to next message
EL Jack is currently offline  EL Jack
Messages: 5
Registered: February 2011
Esquire
That's all very helpful, many thanks.
Re: 4 pi, oh my! [message #66246 is a reply to message #66242] Mon, 21 February 2011 22:41 Go to previous messageGo to next message
Matts is currently offline  Matts
Messages: 359
Registered: May 2009
Grand Master
Ok, what kind of drivers in them? xover? do you plan to put some veneer on them?

"lack of compression" haha!! these speakers ARE dynamic...

I use them with 3.5 watt SET and they work great. With the Cary's you'll get some definite pop.
Re: 4 pi, oh my! [message #66252 is a reply to message #66246] Tue, 22 February 2011 12:48 Go to previous messageGo to next message
EL Jack is currently offline  EL Jack
Messages: 5
Registered: February 2011
Esquire
All standard: Eminence drivers and the base crossovers.

I have previously built a small 2-way but the veneer was not entirely successful. I'll need some help to decide what to do, but I'm inclined to go with a basic black paint.

I just can't believe how these things fill the space with no distortion.

After I spend a couple weeks with them I'll do a review on Audiogon as I strongly believe that more people need to be made aware of these.

My guess is that most folks (including me before yesterday) think there'll be some issue with the high frequencies and the cross-over region, but I'm not getting any issues in those places.

I have three other pairs of speakers (Maggies, Meadowlarks, and Polks, former S-phile Class C, B, and C, respectively) but I think these will be at the top of the rotation.
Re: 4 pi, oh my! [message #66253 is a reply to message #66252] Tue, 22 February 2011 13:53 Go to previous messageGo to next message
Wayne Parham is currently offline  Wayne Parham
Messages: 18167
Registered: January 2001
Illuminati (33rd Degree)

We pay extremely close attention to the crossover region, because it is so important to a speaker designed for uniform directivity. See the document attached in my last reply for a complete explanation.

Re: 4 pi, oh my! [message #66256 is a reply to message #66242] Tue, 22 February 2011 17:09 Go to previous messageGo to next message
Matts is currently offline  Matts
Messages: 359
Registered: May 2009
Grand Master
Mine are plywood cabs, finished with a "faux" mahogany finish that an antique finish specialist did to make them look like an old 50's era dark mahogany "hifi" cab. Very nice! He did a lot of stippling on the edges to cover up the ply effect and faux grain, etc. all over with different shades.

There are lots of finish options that are very ez and look good. You can put a piece of fabric over the top and sides and put nice flowers on them if you're married!

Another thing I find most impressive about these speakers is the proper field effect you get when you listen from another room. I haven't heard any other speakers that do this so well- many recordings sound like live music from down the hall.

Enjoy them!
Re: 4 pi, oh my! [message #66257 is a reply to message #66252] Tue, 22 February 2011 17:10 Go to previous messageGo to next message
Bill Epstein is currently offline  Bill Epstein
Messages: 1090
Registered: May 2009
Location: Smoky Mts. USA
Illuminati (3rd Degree)
EL Jack wrote on Tue, 22 February 2011 13:48
All standard: Eminence drivers and the base crossovers.

I have previously built a small 2-way but the veneer was not entirely successful. I'll need some help to decide what to do, but I'm inclined to go with a basic black paint.


I think you'll find that painting plywood or MDF is more work than veneer.

For $75 you can buy a 4x8 sheet of NBL (no black line) walnut, cherry or oak veneer from tape-ease.com. One sheet will do the front, top and sides of both speakers. Use the method described by Bob Brines for gluing it on http://www.brinesacoustics.com/Pages/Articles/Cabinet_Construction/Construction.html

index.php?t=getfile&id=324&private=0

You don't have to trim with a router, a sharp block plane or even a utility knife will do fine to get within an 1/8th, then sand flush.

Enjoy! (and go JBL and B&C as soon as you can!)
Re: 4 pi, oh my! [message #66262 is a reply to message #66257] Wed, 23 February 2011 02:41 Go to previous messageGo to next message
steve f is currently offline  steve f
Messages: 228
Registered: May 2009
Master
Bill,
What makes the bigger difference, the change of woofer or tweeter?
Steve
Re: 4 pi, oh my! [message #66276 is a reply to message #66262] Wed, 23 February 2011 08:45 Go to previous messageGo to previous message
Bill Epstein is currently offline  Bill Epstein
Messages: 1090
Registered: May 2009
Location: Smoky Mts. USA
Illuminati (3rd Degree)
I don't know the Omega woofer, only the Delta from the old Theatre 4, but going to the JBL 2226 has to make the bigger change as it's in the music-range, 150 to 1600 Hz. Also, the 2226 has a mid-range that just kills all those darling little 86dB, 6" drivers in the $10,000 speakers I've heard.

The PSD-2002, while not in the class of the B&C DE-250, is very easy on the ears, doing a great job of conveying the timbre of the music.

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