[Rick Craig]

I'll be in Houston next weekend and Fred Thompson graciously offered to host a listening session.
Come hear something truly different!

Sunday August 7th 2pm till...



DIRECTIONS:

The subdivision is off of Eldridge Parkway in Northwest Houston
Coming from I-10, go North about 4.5 miles on Eldridge Pkwy.
The entrance street is Lakes On Eldridge Blvd.
It's the only light between Clay Rd and Tanner Rd.
The Subdivision is gated/guarded.
I'll notify the security guard to admit you when you tell him/her
you're coming to Fred & Linda Thompson's house at 12110 Medina Bend Ln.
After you drive through the gate, TURN LEFT EVERY TIME YOU COME TO A
STOP SIGN:
Left on Lake Shore Ridge
Left on Lake Center Run
Left on Summer Falls
Left on Emerald Brook
After that last left turn you're facing my house
It's a two story red brick at 12110 Medina Bend Ln
Look for a blue Nissan Sentra parked in front
If you get lost telephone 281-381-8830 and a rescue party will be
dispatched.

[jimdgoulding]

For those of you who don't know, Fred is one of the main guys and girls belonging to The Houston Audio Society and with his wife, Linda, a host extraordinaire.

[FredT300B]

Everybody is invited. RSVP's are not necessary - just come on over and join us. It will be an open house kind of thing officially starting at two and ending when the last person leaves, but try to arrive between 1:30 and 4:00 if you can. We'll provide snacks, soft drinks, bottled water and some adult beverages too.

Each of the mystery speakers will be bi-amplified with its own two channel amplifier. I can't describe the speakers in too much detail because Rick likes surprises, but try to imagine something with lots of drivers and a long narrow convex curved baffle. The DEQX HDP Express will be used as processor, active crossover and preamp, receiving its signal from the S/PDIF output of a Cambridge Audio Azur 840 CD player.

In another listening area we'll have an Oppo BDP-95 player and a Krell integrated amp driving the Selah Audio 2.5-way Texas Revelator Tower speakers.

[cstory]

Sooooo..... How did it go? Are there any pictures of the mystery speakers that Rick brought? And what did they sound like? Curious people want to know. 

[FredT300B]

This was one of the most interesting demonstrations I've ever attended. When I first saw the picture of the CBT line arrays on the cover of the current Parts Express catalog I assumed they were some very impractical project from some clueless person who hadn't read Speakers 101. But when I saw and heard Rick Craig's new CBT arrays, saw them measured, and heard a technical explanation of how they work, I was impressed.

This new technology has a downside - cost and complexity. Any array using so many good quality drivers is going to be expensive, and when you add to that the cost of an electronic crossover and biamping, it won't be a small investment. So everybody should listen and decide for themselves. But it also has an upside - the soundstage and dynamic capabilities of a line array without the inconsistent sound as your ears move up or down. Sitting or standing the sound stays exactly the same.

I've added a gallery of pictues from the session. Sorry, no captions, but you can figure out what's happening in each one.
http://www.audiocircle.com/index.php?action=gallery;area=browse;album=5742

[cstory]

Thanks for posting the pictures.

So, these are a scaled down version of the ones featured on Parts-Express. It's a little hard to tell the scale, are those 4" or 5/1/2 " woofers? How low did they go with the measurements?

They look a bit more practical than the floorstanding ones that were pictured in the earlier posts, and are down to two amplifier channels instead of 7 or 8 (I forget how many channels Rick said he was looking for for the floor standers).

So relative to your TRT speakers, how would you compare the overall sound of the two designs?

I'd love to hear them, and I'm guessing they are making their way to the Chicago listening session, but it's a bit too far away for me to make it there.

Thanks again for the pictures.

Chuck

[jimdgoulding]

"Chuck-E's in love. ."  Hi, Chuck.  Thanks, Fred.

[rklein]

Hi Fred:

As a fellow TRT builder , I too, am very interested in how your TRT's faired at your get together.

This is off topic, so maybe you can PM me but I am also interested in how you liked the speakers you built from Wayne Parnham and how they compared to your TRT's.

Regards,

Randy

[rklein]

After posting, I realized that this is actually Rick's(Selah) Circle.   

I apologize to Rick for asking about another speaker kit on his Circle.  I asked my question in the spirit of DIY'ing.

Regards,

Randy

[Rick Craig]

After posting, I realized that this is actually Rick's(Selah) Circle.   

I apologize to Rick for asking about another speaker kit on his Circle.  I asked my question in the spirit of DIY'ing.

Regards,

Randy

No problem - Wayne's a good guy!

[Rick Craig]

Thanks for posting the pictures.

So, these are a scaled down version of the ones featured on Parts-Express. It's a little hard to tell the scale, are those 4" or 5/1/2 " woofers? How low did they go with the measurements?

They look a bit more practical than the floorstanding ones that were pictured in the earlier posts, and are down to two amplifier channels instead of 7 or 8 (I forget how many channels Rick said he was looking for for the floor standers).

So relative to your TRT speakers, how would you compare the overall sound of the two designs?

I'd love to hear them, and I'm guessing they are making their way to the Chicago listening session, but it's a bit too far away for me to make it there.

Thanks again for the pictures.

Chuck

4" woofers in this design. Without equalization -3db @80hz (sealed box) and perfect for use with a subwoofer. With the EQ extension is significantly lower and the -3db depends on how much headroom you want (40hz for this owner). Four channels of amplification and a very easy load of 4 ohms.

This is quite different than the PE design and meant for applications on-wall, in-wall, or sitting on a subwoofer. The owner lives in Houston so this pair won't be in Chicago; however, I am working on the next pair with custom RAAL ribbon tweeters for future delivery to St. Louis.

[FredT300B]

Hi Fred:
As a fellow TRT builder , I too, am very interested in how your TRT's faired at your get together.
Randy

This begs that existential question from Shakespeare's Hamlet: "Tubey, or not tubey, that is the question". 

The ArcArrays were driven by an identical pair of 500w/ch D-Sonic Magnum 500S class D amps. The TRT's were connected to a pair of 40 watt Audio Mirror parallel 6C33C SET tube amps, in turn driven by a tube preamp with tube rectification. While most amps sound pretty much the same to me, these do not. Further adding to the differences was the fact that I've measured a 4dB room related peak at about 40hz in the room where the TRT's were located, while the much larger room where we auditioned the ArcArrays tends to not reinforce bass very well.

So to answer your question, the TRT's sounded romantically lush and warm, while the ArcArrays sounded accurate. But the TRT's are still my best sounding speakers when driven by a well matched solid state amp like my Krell integrated. Better than my Selah Audio XT-8 line arrays in all areas except for scale, dynamics and the ability to play really loud without distortion.