I grew up in Oakland. It's Tower of Power and Earth Wind and Fire on a belt drive turntable!

allen, sending you a PM.

i heard some similar to that, verrry nice sound. the problem with infinity is they are not efficient. a guy at work has some he pushes with 2 adcom 200 watt amps, bridged more than that. i have some klipsch klf 20's powerd by 1 100 watt nada amp. i cant stand to be in the room if i crank it, and not even close to clipping. he clips his amp quite a bit.

i looked up some of the infinities. some were as low as 90db for 1watt/1meter were the klispch are 100db or so. what that means is, at 128 watts, the infinity is putting out 110db, the klipsch needs 8 watts to put out 110db.

still, a very nice sounding speaker and an even better deal. some people have all the luck.

The way these speakers are configured is there are separate inputs for the woofers and separate inputs for the mid range/tweeters. If you're only using one amp, you bridge the inputs (banana plugs) and then the feed goes to all the drivers.

I wonder if they meant for the user to tie in two amps rather than just a single.

I owned a 555 for about ten years. Very clean and superbly reliable- I gave it to a friend only because I bought a Mac 602.

You got a great deal- I don't know of any Electrostatic speaker that doesn't require gobs of power. Clean and open sound yes- efficient, no. They're also weak on bass- supplement them with a good subwoofer and I bet you'd be really amazed. Also just noted above post- bi wire them and they should sound even better.

Looking back on speaker design over the years, did makes figure out how to produce more sound out of smaller speakers, or did the market just die out on huge speakers and effect it had on furniture, neighbors, and wives? Looking at those speakers, it would seem the true benefit would be if they were driven with some heavy power. But it seems this would be enough to fill a stadium. For normal listening, aren't they just a bit impractical? Just wondering?

Loudspeaker "efficiency" is kind of an irrelevant metric to gauge sound quality on though (IMO). Most higher-end stuff comes in well under 100db 1w/1m (I've heard some phenomenal systems with 1w/1m barely over 80db). System/brand/model (ohm) loads vary greatly (2Ω - 16Ω) making it that much more of a useless statistic (but good for marketing). In quality systems, the drivers are usually better damped, both physically (surrounds/spiders) and mechanically (VC's/motors). The filter networks are typically more elaborate than a single cap/coil as well. The end result is usually a more balanced, neutral sound, at the expense of efficiency (quality vs. quantity). That said, not all "inefficient" loudspeakers are quality by default! YMMV.

I shouldn't pick nits but current is the key - not power. Many amps have high power & no current. Others (mainly Euro amps) have lower power & good current. Ohms law variant: Power (watts) = Voltage X Current (amps)

The GFA-555, albeit a reasonably crude sounding amp (imho) had decent current capabilities. Krell was the goto (in the day) for somewhat better sound. GFA stood for Great F***ing Amp.

Emits were ribbons & therefore not a stat.

Ian

The Adcom 555 is a good choice of course a McIntosh amp (McIntosh 2300, my choice if it were me) would be the ultimate. I sold the Infinity Quantum Series speakers and we used 270 to 300 watt amps to run them. We had two pairs of the next to the top of the line Quantum 2's & 3's. Played a track from a Boston LP organ music and they thought the electrical transformers in the building were going. Sound was phenomenal, huge amount of clean bass. These should give you plenty of bass and sweet, sweet mid & highs as you have found out. Nothing like the big speakers of the 70's and early 80's. Great that the wife appreciates them.

Check out his site as it has great information on the Emit tweeters and L-Emin mid drivers. BobbyShred's Vintage Infinity Speaker Page

Here is a picture of my score from a few years ago JBL 4343 Studio monitors just about completely restored. Not my picture but the exact speakers. Only 175lbs each and they need a lot of power as well.
http://forums.pelicanparts.com/uploa...1260503633.jpg

Or, why not two amps per speaker. Heck, you got such a good deal, you ccan afford a lot of clean power to drive 'em.

A Pink Floyd concert LP, like Breathe, will showcase that array.

(oh, and you should really look for a nice subwoofer or two, (with dedicated amps) Just to make sure your neighbors a block or two away can enjoy the experience.)

:eek:

Well, I picked up the Adcom GFA-555 last night. The guy who sold it to me was real nice. There was not a scratch on it! This thing looks as if it just came out of the show room. Got it for $300.

He said that using high quality speaker wire really made a difference. He had this eight strand speaker wire that he was using. It looked like 8 individual 18 gauge wires - 4 for positve, 4 for negative - bundled together.

I'm going to hook the whole thing up this weekend and fast forward to the flute and flugelhorn solo in Sparkling in the Sand by Tower of Power. That's a good test of highs and lows.

Am I really going to need a separate sub-woofer? Also, how would I hook that up as there are only left and right speaker outputs on the Adcom?

http://forums.pelicanparts.com/uploa...1260536765.jpg

Your preamp will handle the pre-outs for a powered sub.

Listen to something like hip-hop with some bass to determine how they reproduce the lows and then make your decision.

i agree. i did not mean best efficiencey meant best sleaker. i heard the infinity a loooong time ago and was extremly impressed. but i was just stating that you need a lot more power to drive the infinities. i think the guy at work thought it was impressive that he was clipping a 200+ watt amp, but in reallity, the sound volume was less than what my klipsch were putting out with a 100 watt amp. i just could not believe his ears were not bleeding so i looked up the specs on his speakers.


i dont know about the high end speakers, but most lower end are not set up for bi-amp. mine are, although i dont consider mine low end. i bi-wire mine. i bought the 4 conductor 12ga wire from lowes, same stuff we use for pro sound. on each side, i connect 2 wires to + and -. then at the speaker i have 4 terminals, 2 foe the highs and 2 for the lows. i did not think this would make a difference but i could tell the highs were much clearer. the idea is that the high frequencies and lows use seperate cables.

2 amps bridged, use one amp for each side. or you could bi amp with 2 amps. left side of one for the highs, left side of the other for the lows.you would need a smaller amp for the highs as they dont handle as much power, unless you had a crossover that could reduce the level. i have not seen anyone bi-amp a home system. i thought about it at one time, but thought trying to balance the highs to the lows as far as power/volume would be a pain, plus the cost.
i bi-amp my PA, 2000 watts for the subs and 1200 for the top box. i could tri-amp if i had another crossover and we got another powered speaker for monitors.

Most of the Infinity speakers such as the RS-II had very good deep bass. Try them out but I doubt that a sub will be needed. Sub woofers were a necessity after the physical size of speakers started declining to replace the bass that used to be generated from large woofers and large cabinets. These qualify for large cabinet design:D:D My guess is you will be very pleased with them. Bi-amping them would be the next step for sound quality.

This was meant pretty much tongue in cheek, I guess I should have used green type. I think with your new amp, you will have more than what you need. I imagine the bass from these will be very nice, rich, deep, yum!

Maybe pair up the amps, otherwise, just enjoy!

(and if you want to see how carried away you can get, check out this guy's sound systems!)

http://www.polkaudio.com/forums/showcase/view.php?userid=18511

Great find.

Craig,

Those Infinity's are nice. Go on ebay and look for any Phase Linear power Amps. Gobs of power. I have one 700B pushing my 15 and 12 in drivers. another 400 series pushing my horns and tweeters. Two more pushing 2 other subs.

I attached some photos.

Also Ian MaCarthur turned me on to the better CD units like the "Rega Planet" and "Cambridge Azur CD players". I also spin vinyl with a Micro Seiki DDX 1000.

Those are a great buy...Don't piss off your wife..I do it all the time. Not intentionally..But, Robin Trower is awesome cranked....Thank god she is cool.

Bigger Speakers are BETTER!!! Bigger pressure waves...

Read this Pelican thread also.. Allot of great input from the same guys here!

http://forums.pelicanparts.com/off-topic-discussions/468913-audiophiles-did-you-get-dupped-into-cd-craze.html

Bobhttp://forums.pelicanparts.com/uploa...1260567501.jpg
http://forums.pelicanparts.com/uploa...1260567538.jpg

Craig,

I noticed you like Tower of Power and Earth Wind and Fire!..Great Music! That was the music I grew up with..I graduated from High school in 79, when those bands were popular. Believe me...spend some money on nice stuff I.e. Good amplifiers and vinyl/Cd players...You wont be sorry!

Do you know what the song Sqwib Cakes sound like thumping 15's and 12's with 2 HP of amplifiers is like? Unbelievable!.....:) Barry sax in front of your face...Ha! You can smell there breath...:)

Bob

Bob, does NASA know you have thier gear! Yikes! How are they supposed to track the space shuttle when you ripped all their toys!?!

Nice rig.

Oh and I completely forgot about squib cakes!!! That is an awesome instrumental. Chester Thompson on keyboards for about half the song. Let's see how do the lyrics go? Oh yea,

Squib cakes
Squib cakes
Squib cakes
Squib cakes

The end!

This is going to be a low-productivity week end! Just a lot of old school soul and a lot of me annoying the neighbors!

that was what impresed me. the bass seemed very smooth.

try the bi-wire, you might be surprised, i was.