im new to building home stereo so please forgive my ignorance and lack of knowledge.i bought a adcom gfa 555ii two channel amp and wondered how many speakers could i hook up to this 200 watt per channel amp?i have realistic mach 2,s 160watts,paradigm 9v2 175 watts,technics sb-lx90 100 watts and all 8ohms.
adcom gfa 555ii amp?
- Thread starter jonnid68
- Start date
Register to hide this ad
JoeESP9
ESL's & tubes since 83
It has two pair of speaker terminals that would indicate one pair of speakers.
Seriously, if you want to connect multiple pairs of speakers get a speaker switchbox.
https://www.amazon.com/Improved-Sel...x=speakers+switch,aps,155&sr=8-11-spons&psc=1
FWIW: Speaker wattage ratings are worthless and useless. As long as you pay attention to the sound you can safely use just about any amplifier with any speaker. One of two things will happen if you push the levels to loud. The amp will run out of power and will sound strained. The speakers will reach their loudness limits and sound strained. In either case the solution is simple, TURN DOWN THE VOLUME..
Seriously, if you want to connect multiple pairs of speakers get a speaker switchbox.
https://www.amazon.com/Improved-Sel...x=speakers+switch,aps,155&sr=8-11-spons&psc=1
FWIW: Speaker wattage ratings are worthless and useless. As long as you pay attention to the sound you can safely use just about any amplifier with any speaker. One of two things will happen if you push the levels to loud. The amp will run out of power and will sound strained. The speakers will reach their loudness limits and sound strained. In either case the solution is simple, TURN DOWN THE VOLUME..
david1111
Barba non facit philosophum
@jonnid68
Hi jonni.
The switchbox will certainly make it easy to select your speakers,.
I have the same amp, and I connect my Kef R107's to it with banana plugs, and I connect my subwoofer with spade connectors. This was recommended in the sub manual.
The GFA 555ii has a huge torroidal power supply, in fact it's 25 or 30% larger than the first 555 model. It will drive a 2 ohm load all day. (Although you'd probably want to install a computer fan on it).
If you connect 2 pairs of 8 ohm speakers, the load drops to 4 ohms. If you connect 3 pairs of 8 ohm speakers to it, the load drops to 2.6 ohms. The load would dip below 2 ohms occasionally, depending on the music being played, but that wouldn't be a problem.
So, if you find that yer getting some signal degredation from all the extra connections thru the switchbox, you have this option.
The nice thing about the switchbox, of course, is being able to play your music thru any or all of the speakers individually.
I just thot you should be aware that your GFA 555ii is a bit of a beast, and can handle a lot of loading. It also sounds pretty darn good, eh? Btw, they really sound great with a tube preamp.
Anyway, happy listening.
Cheers.
Dave
Hi jonni.
The switchbox will certainly make it easy to select your speakers,.
I have the same amp, and I connect my Kef R107's to it with banana plugs, and I connect my subwoofer with spade connectors. This was recommended in the sub manual.
The GFA 555ii has a huge torroidal power supply, in fact it's 25 or 30% larger than the first 555 model. It will drive a 2 ohm load all day. (Although you'd probably want to install a computer fan on it).
If you connect 2 pairs of 8 ohm speakers, the load drops to 4 ohms. If you connect 3 pairs of 8 ohm speakers to it, the load drops to 2.6 ohms. The load would dip below 2 ohms occasionally, depending on the music being played, but that wouldn't be a problem.
So, if you find that yer getting some signal degredation from all the extra connections thru the switchbox, you have this option.
The nice thing about the switchbox, of course, is being able to play your music thru any or all of the speakers individually.
I just thot you should be aware that your GFA 555ii is a bit of a beast, and can handle a lot of loading. It also sounds pretty darn good, eh? Btw, they really sound great with a tube preamp.
Anyway, happy listening.
Cheers.
Dave
I have a Adcom 6-speaker selector and I will occasionally play a pair of speakers 8/4 ohm or 8/8 and my 555 doesn't even break a sweat especially if I am only playing them at moderate volume.
Congrats on the 555ii it is a good amp that will be able to play just about anything you hook it up with and do it well. What preamp are you using with it?
Congrats on the 555ii it is a good amp that will be able to play just about anything you hook it up with and do it well. What preamp are you using with it?
restorer-john
Addicted Member
The Adcom will have fun with those speakers, especially the Mach 2s.
Hint: It isn't loud until you light up the mid/treble protectors (festoon bulbs) on the Mach2 crossover boards and you see them flash through the reflex port tubes. Yeah!
Hint: It isn't loud until you light up the mid/treble protectors (festoon bulbs) on the Mach2 crossover boards and you see them flash through the reflex port tubes. Yeah!
Schurkey
Well-Known Member
They WERE when they were new. They are a long ways from new at this point in time.
They're old enough now that they very likely need to be refreshed (new capacitors, verify bias and DC offset)
DavidF
Active Member
Hard to give a certain answer. Most home speakers are designed presuming the pair are the only systems energized by an amplifier. Two pairs could be OK with a lot of 'depends on this or that'. Maybe a good start is to know what you are wanting to accomplish wiring up two or more pairs?
