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The Most Interesting Product at GPAF? [message #3047 is a reply to message #3024] Mon, 08 May 2006 05:40 Go to previous messageGo to next message
FredT is currently offline  FredT
Messages: 704
Registered: May 2009
Illuminati (1st Degree)
What did you find the most interesting?

For me it was the little box that Skip Pack brought to the Dallas Audio Club room and hooked up to the system. The Squeezebox from Slim Devices was hard wired to his laptop, whose external hard drive held more than 100 CD's in lossless FLAC file format. We played it thorugh the Lite Audio DAC-60, and it sounded very good to me. This device certainly gets an A+ for convenence. I'm still undecided about whether it sounds as good as a CD in a good quality player because none of the CD's available in our room duplicated the CD's Skip had recorded on his external drive, so we couldn't do a direct comparison.

We both live in Houston, and sometime after the meet Skip and I plan to get together to do some CD player / Squeezebox comparisons. We'll post our finding on the ART digital forum. In the meantime, if somebody has done some A/B comparisons between a Squeezebox and a CD player please post your findings on the Digital forum. Picture of the Squeezebox sitting on my CD player here:

http://greatplainsaudiofest.com/2006/Photos/DSCN0236.JPG


Re: Photos online [message #3054 is a reply to message #3032] Mon, 08 May 2006 15:18 Go to previous messageGo to next message
DRCope is currently offline  DRCope
Messages: 160
Registered: May 2009
Location: Brooklyn, CT
Master
Hi Wayne,

From what I hear, the show was terrific! Thanks for helping Mario out, and thanks to Mark Margiotta for helping with the shipping logistics!

I'm sure the photos are great, but even with a hispeed connection, these are way big for online viewing. Suck 'em through iPhoto or somesuch and shrink those babies down to about a 1/13 the size!

Dave

237 & 238?? [message #3059 is a reply to message #3032] Tue, 09 May 2006 13:52 Go to previous messageGo to next message
GarMan is currently offline  GarMan
Messages: 960
Registered: May 2009
Illuminati (2nd Degree)
Wayne, I'm sure you'll write some commentary when you have the time, but in the meanwhile, tell me something about the speaker in photos 237 and 238. Are they 6 inchers?

Re: 237 & 238?? [message #3060 is a reply to message #3059] Tue, 09 May 2006 14:06 Go to previous messageGo to next message
Wayne Parham is currently offline  Wayne Parham
Messages: 18783
Registered: January 2001
Illuminati (33rd Degree)

That's an Alpha 8 in a 1.5ft3 cabinet. Fred Thompson wanted to make something similar to a Tower two π but smaller, using one π parts. Sounds very good, by the way.

Re: 237 & 238?? [message #3061 is a reply to message #3060] Tue, 09 May 2006 14:22 Go to previous messageGo to next message
GarMan is currently offline  GarMan
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Registered: May 2009
Illuminati (2nd Degree)
Must be the perspective, but in pic 238, it looks tiny.

Re: 237 & 238?? [message #3062 is a reply to message #3061] Tue, 09 May 2006 14:32 Go to previous messageGo to next message
Shane is currently offline  Shane
Messages: 1117
Registered: May 2009
Illuminati (3rd Degree)
I think Fred said they were around 36" tall, about 11.5" deep and about 10" or so inches wide. He also said they were about $200 or so a pair to build. There is a shelf right below the port to make the cabinet volume right for the Alpha 8. He said you could fill the bottom section with sand or whatnot if you wanted to. They sounded pretty good with the Heathkit rebuild amps puching them.

Re: 237 & 238?? [message #3065 is a reply to message #3062] Tue, 09 May 2006 15:05 Go to previous messageGo to next message
GarMan is currently offline  GarMan
Messages: 960
Registered: May 2009
Illuminati (2nd Degree)
I don't doubt that they sound very good. The Pi-Ones I built are one of my favorites. Probably one of the best value in DIY.

Re: 237 & 238?? [message #3069 is a reply to message #3060] Tue, 09 May 2006 16:40 Go to previous messageGo to next message
FredT is currently offline  FredT
Messages: 704
Registered: May 2009
Illuminati (1st Degree)
They're almost a Studio One Pi "tower" except for this pair I combined the Alpha 8 woofer with the GR Research T6 tweeter. It's a 6 ohm driver with an advertised sensitivity of 96dB. Like the Vifa DX25 I used in a previous incarnation of this speaker, the GRT6 has a low resonant frequency and good power handling capacity. The 96dB sensitivity makes the sound a bit brighter than it would with the Vifa tweeter.

The enclosure is 9.75" wide, 12.75" deep, and 36" tall. The 9.75" width is about the narrowest I could go with the 8" woofer. The 12.75" depth is determined by the 11.25" standard width of 12" mdf boards plus the 1.5" thickness of the combined front and back panels. The 36" height is what's needed to get the tweeter to ear level. These dimeinsions yield a 1.8 cu ft volume, which is a bit too much for the Alpha 8, so I implemented a separate 6" high chamber in the bottom which could house the crossover or, as I implemented here, it can be filled with sand or shot. The volume is 1.5 cu ft, and it's tuned to 54hz with a 4" port.

The crossover is 1st order using a 0.47mH Jantzen 15 ga air core inductor in series with the woofer and a 6.0uF Northcreek Zen cap in series with the tweeter. There's also a 2 ohm resistor in the tweeter signal path that's bypassed by a switch on the speaker terminals, and a 16 ohm resistor across the tweeter terminals.

The objective of this design was to build a speaker that's inexpensive (about $100 per plus enclosure materials cost), efficient (95dB), has an acceptable WAF, and of course, sounds good too. The WAF drove the decision to use a narrow enclosure.

Asking the builder whether his speaker sounds good is like asking a mom whether her baby is pretty, or a cable maker whether cables make a big difference, but I'm more than pleased with the sound. I told Wayne he should offer a narrow tower enclosure as an option with the Studio One Pi. The Two Pi tower is a better speaker, but not everyone has a wife who would permit such a large speaker in her house. The One Pi tower, as I said, has a much higher WAF.



Also [message #3071 is a reply to message #3069] Tue, 09 May 2006 17:00 Go to previous messageGo to next message
FredT is currently offline  FredT
Messages: 704
Registered: May 2009
Illuminati (1st Degree)
I forgot to mention this enclosure is very easy to build because you are starting with pre cut 11.25" wide mdf boards. You cut all the panels exactly 36", then you trim four of them down to 9.75" for the front and back panels. The other four you use in their full 11.25" width for the sides. The top and bottom panels are already the correct 11.25" depth, so all you have to do is to cut them to the required 8.25" width. My yard charges 70 cents/ft for the precut mdf boards, so the total for the 32' needed to build two enclosures is just south of $25.

Re: Here at the 330 Abbeyfeale Room. How about this On? [message #3106 is a reply to message #3026] Sat, 13 May 2006 18:53 Go to previous messageGo to previous message
ping is currently offline  ping
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Registered: May 2009
Esquire

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