Impedance and Sound Quality

[UFO]

I think the best car system I ever had was with a pair of EPI M120b home speakers, laying on their backs in the hatch of a 1973 Plymouth Duster and powered by a 12W/channel Sanyo under-dash cassette deck (remember those?) and a cheapo 5-band graphic EQ unit with something like 15w/ch boost made by a company called Royal Sound.

I'm fairly certain those speakers were 8 ohm but they put everything I've had since to shame. Unfortunately they were huge particle board boxes that basically filled the car, and the woofer cones eventually just fell apart from temp/humidity extremes and age (I bought them in something like 1978, mind you.)

The question - finally: Does impedance affect sound quality in any way? IOW, is there any advantage in SQ between, say, a pair of 2 ohm speakers vs. 4 or 8?

Someone recommended that I try Adire Audio Extremis drivers for more raw power, but they're 8 Ohm speakers. I have two pairs of MB Quart PCE216s installed and I think at least one pair is fried. Can I swap in a pair of Adires and run two pairs of speakers having different impedances off of the same four-channel amp without destroying the amp?

Thanx,

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[squeak9798 5,000+ posts]

The question - finally: Does impedance affect sound quality in any way? IOW, is there any advantage in SQ between, say, a pair of 2 ohm speakers vs. 4 or 8?

No.

Someone recommended that I try Adire Audio Extremis drivers for more raw power, but they're 8 Ohm speakers. I have two pairs of MB Quart PCE216s installed and I think at least one pair is fried. Can I swap in a pair of Adires and run two pairs of speakers having different impedances off of the same four-channel amp without destroying the amp?

Yes.

However, you could not use the Adire Extremis on the MB Quart passives. And you would need a tweeter for the Extremis as well as some way to bandpass filter them (highpass and lowpass them).

 

[engineerdude 10+ year member]

Speaker impedances are the load that your amplifier is carrying. Think about if you were skipping down a hallway, now if you skipped down that hallway holding 40 lb. dumbbells; your skip would turn into a run/walk wierd thing. The skip is the musical signal... the more you load it, the more distortion that can be played.

 

[engineerdude 10+ year member]

Keep in mind that most amplifiers are capable of running at somewhat higher loads.. so the answer to your question is that impedance can affect SQ.. but probably only at extremes ( 4 ohm amp running at 1/2 ohm load),

 

[adam71 5,000+ posts]

In all reality the the lower the resistance the higher the distortion which means the lower the SQ. This may or may not be audible.

 

[azbass 5,000+ posts]

2 omh sounds better than 4 omh

 

[adam71 5,000+ posts]

2 omh sounds better than 4 omh

2ohm is louder than 4 ohms but it does NOT sound better.

 

[JimJ 5,000+ posts]

2ohm is louder than 4 ohms but it does NOT sound better.

1. Maybe it's louder, maybe it isn't.

2. Let's do an ABX test on that one //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

 

[azbass 5,000+ posts]

he thought i was serious?

 

[JimJ 5,000+ posts]

he thought i was serious?

Yeah...

 

[adam71 5,000+ posts]

he thought i was serious?

You weren't?? I could have sworn you were since you didn't use any smileys.

 

[adam71 5,000+ posts]

1. Maybe it's louder, maybe it isn't.
2. Let's do an ABX test on that one //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

What the fuck are you talking about?? If you have a 2 ohm set of speakers they will receive twice the power that a 4 ohm speaker receives if it is the same amp. That is also taking into consideration that both sets of speakers have the same sensitivity.

 

[JimJ 5,000+ posts]

What the fuck are you talking about?? If you have a 2 ohm set of speakers they will receive twice the power that a 4 ohm speaker receives if it is the same amp. That is also taking into consideration that both sets of speakers have the same sensitivity.

Your statement...and like I said before, that's not always the case //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif I know plenty of amps that will do the same power @ 2 ohms that it does at 4...or 4 and 8, or whatever. Both solid state and otherwise //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

As for the second part of what I said, if there were any links to credible ABX tests that show conclusively that a lower impedance sounds worse to the ear, I'd love to read them. If it's a measurable difference, but splits 50/50 to a group of listeners...it's all a bit academic.

 

[adam71 5,000+ posts]

Your statement...and like I said before, that's not always the case //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif I know plenty of amps that will do the same power @ 2 ohms that it does at 4...or 4 and 8, or whatever. Both solid state and otherwise //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif
As for the second part of what I said, if there were any links to credible ABX tests that show conclusively that a lower impedance sounds worse to the ear, I'd love to read them. If it's a measurable difference, but splits 50/50 to a group of listeners...it's all a bit academic.

My first post said that it may or may not be audible so I didn't necessarily say it sounded worse. I just stated that the lower the resistance the higher the distortion.

 

[squeak9798 5,000+ posts]

I just stated that the lower the resistance the higher the distortion.

in the amplifier.....which if it's within it's linear range will still likely be an inaudible amount //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif
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