billVonr

Speaker Impedance

I’m a neophyte to this forum, but from reading some of the posts, there is some significant knowledge here. I would like to tap into that expertise in the hope of avoiding a potential problem.

I had some good quality speakers (3-way @ 8 ohm) installed in the cabinetry of my family room when the home was built. I’ve connected them to an Aiwa CX-NA71 compact disk stereo system, and I’ve included a video/aux connection to my TV to improve sound for movies and DVDs. Recently, the stereo decided to give up the ghost without warning, and my son has offered his system (Aiwa CX-NA555) as a replacement. Herein lies the dilemma:

The original system (CX-NA71) specs say it will accept speakers of 6 ohms or more and surround speakers of 16 ohms or more. The potential replacement (CX-NA555) specs say it will accept “High Frequency” speakers of 8 ohms or more, “Low Frequency” speakers of 4 ohms or more, and surround speakers of 8 to 16 ohms (note: The “Low Frequency” connections are for bare wires, which is the same way my installed speakers connected to the original system).

Does anyone see a problem with the potential unit and my installed 8-ohm speakers? Any advice or guidance will be greatly appreciated. Thanks.

Bill

John Garcia

From what you've said, it sounds like it will be OK.

"The trouble with the world is not that people know too little, but that they know so many things that ain't so." - Mark Twain

HT: Marantz SR-8300, MA500 monoblocks x 2, 5X GR Research A/V-2s, Adire Audio Tempest sub, Denon 2900, Oppo 980H, Toshiba HD-A2, RC2000MkII remote, Panamax 5100, Panamax Max2 sub, Slim PS2, PS3 60G + 320G USB

Bedroom: Marantz PM-7200 Integrated, GR Research A/V-1s, Sony 222ES SACD, RC3200 remote, Panamax M8EX

Audio: Audioquest * Video: Bluejeans

My DVDs My HT

Nhoj

Sounds like that aiwa might be bi-amped. Were there more than two connections per original speaker? If so, you'll get either highs or lows but not both unless you mod your speakers for bi-amping.
The other problem is that those little systems use very efficeint speakers to overcome their low power output. Connecting to a normal speaker might drive the itty-bitty amp to hard and blow it.
I would suggest using the original aiwa speakers or upgrading to a receiver.

billVonr

Nhoj, thanks for your reply. I’m not familiar with the term bi-amped. My cabinet speakers have 2 wire leads which connect to the back of the Aiwa system. I noticed on the potential replacement unit (CX-NA555) that the speakers have a phono plug which connects to the “High Freq” terminal and a pair of loose wires which connect to the “Low Freq” terminals (+ and -). Is this a bi-amped connection, and if so, how do I connect my cabinet speakers correctly?

Re: power, the old unit had 100 watts/channel output, and the replacement unit has 50 watts/channel (200 Hz – 20KHz, THD less than 1%, 8 ohms).

Bill

John Garcia

It does sound like a "quasi-biamp" setup, but if it says 8 Ohms are OK, that's what most speakers are. Now, if it doesn't have a lot of real world power, it may not give you the best results. The "low" frequency wires are possibly intended to drive a bass module / passive sub, and the "high" frequency would be some small satellites, would be my guess.

"The trouble with the world is not that people know too little, but that they know so many things that ain't so." - Mark Twain

HT: Marantz SR-8300, MA500 monoblocks x 2, 5X GR Research A/V-2s, Adire Audio Tempest sub, Denon 2900, Oppo 980H, Toshiba HD-A2, RC2000MkII remote, Panamax 5100, Panamax Max2 sub, Slim PS2, PS3 60G + 320G USB

Bedroom: Marantz PM-7200 Integrated, GR Research A/V-1s, Sony 222ES SACD, RC3200 remote, Panamax M8EX

Audio: Audioquest * Video: Bluejeans

My DVDs My HT

billVonr

Thanks to all for your advice and comments, but I still need some help.

I attached the wire leads from my speakers to the low frequency connections on the stereo (NSX-A555), but there was almost no sound coming out of the speakers. I think these speakers somehow need to be connected to both the high frequency (2 phono jacks) and low frequency (2 pairs of + and - wire connections) ports.

Any tips on how I do this? I sense this has something to do with the "biamped" condition mentioned previously. I'm sorry, but this is new territory for me, so some further knowledge and some specific instructions would be most appreciated. Thanks.
Bill