Yamaha A-S500 Impedence selector

[admin_exported]

Hi all

Getting very confused about the impedence selector on the back of my yamaha amp.

I have a pair of wharfedale 10.6 speakers which are 6 ohms and bi wired connected to the amp as speakers A

And i also have a pair of B&W 602 S3's which are 4 ohms and bi wired connected to the amp as speakers B

The problem ive got is When I select speakers B on the amp, the B&W's sound terrible, as soon as i select Speakers A (wharfedale 10.6) they sound amazing.

Im just wondering is this because my impedence switch is set to High, should it be set to low??!

it says in the manual the following :

Set the position to HIGH when :

If you use one set (A OR B) the impedence of each speaker must be 6 ohms or higher.

If you use 2 setes (A and B) simultaneously, the impedance of each speakers must be 12 ohms or higher

For LOW it says:

If you use one set (A OR B) the impedence of each speaker must be 4 ohms or higher.

If you use 2 setes (A and B) simultaneously, the impedance of each speakers must be 8 ohms or higher

After reading that, i would guess that the impedance switch must be set to LOW as the B&W speakers are 4 ohms where as the wharfedale are 6 ohms.

Im a bit worried if i set the swtich to low i might damage my speakers.

If anyone can help me out that would be great (sorry for sounding like such a noob!)

Jez

 

[ear]

Then it must be ste to low,

If you use one set (A OR B) the impedence of each speaker must be 4 ohms or higher.

If you use 2 setes (A and B) simultaneously, the impedance of each speakers must be 8 ohms or higher

and never have both speakers on at the same time.

each speaker is diferent so diferent regulations can suit eah speaker.try putting loudness at -1,5

 

[Anonymous]

and never have both speakers on at the same time.

Is this bad?? i was planning on buying a new pair of speakers instead of the b&w 602 s3's (as they sound terrible now) so i could have all 4 speakers running at the same time.

 

[ID.]

JezBaker:
i was planning on buying a new pair of speakers instead of the b&w 602 s3's (as they sound terrible now) so i could have all 4 speakers running at the same time.

Any particular reason why you'd want to run 4 speakers simultaneously? Music in 2 different rooms at the same time?

 

[kevinJ]

JezBaker:

and never have both speakers on at the same time.

Is this bad?? i was planning on buying a new pair of speakers instead of the b&w 602 s3's (as they sound terrible now) so i could have all 4 speakers running at the same time.

If you really want to connect two speaker pairs, you might want to buy a new amp because you'll need one that is very stable driving speakers with low impedances. The B&W may be rated 4ohms, but they will probably drop to 2ohms at certain parts of the frequency range. And the Wharfedales will do just the same thing.

So the easy way out is to forget about using 2 pairs at the same time.
Why do you want that anyway? You are using speakers that sound different and you put extra strain on the amp. That strain will make it distort sooner, and sending out a distorted signal will damage the speakers.

 

[Anonymous]

i want to be able to play 4 speakers at the same time just to add more sound. The amp has a Switch for A+B speakers surely for a reason. At some point i plan on having decks and a mixer connected as well, and would like to use the other pair of speakers as monitors.

What if I Bought another pair of wharfedale's with the same ohms just smaller, something like the wharfedale 10.2's??and had just the wharfedale 10.6's and 10.2's in my system or

Could i buy a pair of monitor audio bx2's as they are 8 ohms?

I dont really want to buy another amp if i can help it, only just recently purchased the yamaha A-S500.

 

[Sizzers]

Personally I just don't see the point of running 2 sets of speakers just to add "more" sound. Are you looking to have "double" stereo, speakers at the front and rear for example?

If you want to fill your room with more sound then I would look at some decent floorstanders instead. If you are determined to go down this route then at the very least you will need to use exactly the same sets of speakers otherwise the results will be truly terrible (believe me, I have heard such a set-up).

 

[Anonymous]

Yes i am looking to have 'double' stereo'. Though it would be a good idea, but everyone seems to be saying its a bad one :S

 

[kevinJ]

If you want more sound, maybe you should look for speakers that are more sensitive than the B&W or Wharfs. Maybe something like a pair of Klipsch horn speakers.

And don't make the mistake of thinking that adding a speaker pair will make the system twice as loud, because it doesn't. It devides the available power between the speakers. Theoretically, if an amp can deliver 50watts per channel at 8ohms speaker impedance, it "should" be able to deliver 100watts per channel at 4ohms speaker impedance. In a real world scenario that would be more like 70watts/4ohms, because most amps can't double that power because the built-in powersupply isn't up for that kind of job (has to do with electrical safety laws and/or keeping the price low). To have an idea of what your amp is capable of, look at the number of watts that are printed on the back of the amp. That's the amount of power that the amp uses. For a normal amp, you'll have to devide that number by 2 to get the total power the amp can deliver to the speakers because an amp has an efficiency of about 50%.

I believe the Yamaha is rated at 80watts/channel at 8ohms (only 2 channels), so if you're lucky you'll get 110watts/4ohms. And I hope Yamaha doesn't use a "downhill, full throttle and wind in the back"-way of measuring the poweroutput.

Also, I noticed that you would like to add a mixer, so I guess you'll use the amp to throw parties too. Maybe it would be better to invest in a pair of PA speakers (for the B speakers connection) for the partying stuff, and keep the best you have now (for the A speakers connection) to listen to music, and forget about using both pairs together.