Niles box, 3pr spkrs

[colterphoto1]

Okay gang, getting ready to set up a mini 'whole-house' system. I've got an iMac computer that has music on it hooked up to Yamaha receiver in the office, the heart of any well appointed home. On the 'A' spkr switch is a pair of Dahlquist M905 10" 2-ways in the office which is the main point of this system.

I want to branch off and use 2 or more sets of in-ceiling or ksb1.1's in nearby bedrooms, possible kitchen/laundry as well.

I really like the idea of being able to just use the A/B buttons to switch the whole house on/off. Probably will just set and leave the Niles box as it'll be either whole house/ or not.

Here's the problem, if I hook up my Niles selector box to the 'B' circuit, and run the house system WITH the Dahlquist (which will always be on and should get the most power, hence hooking them up to 'A'), the 1st and 2nd 'B' pair are actually the 2nd and 3rd pair the receiver is pushing. I don't want to overload the amp with too low impedence. THe problem would get worse when I hook up additional pairs. Is there some wiring trick or way to 'fool' the Niles box into thinking there is another pair attached, therefore running its 1st and 2nd pair in series, keeping the receivers load at nominal 8 ohms.

Thanks,

Michael

[dodger]

I've seen either Niles or Adcom boxes that will accept 4. That's at least one more.

dodger

[colterphoto1]

Thanks DOdger, I've got the Niles box for Four pair, The problem is the office speakers, wired OUTSIDE of the Niles box on the 'A' circuit. With two pairs, Niles will just leave them in parallel, so 8+8 ohms = 4 ohm load, then the 'A' pair also in parallel at 8 ohms will drop the load even further, won't it?

I think the way the Niles box works is it 'senses' what is hooked up or just does it mechanically by how many buttons you've got pushed. 1 or 2 pairs stay in paralled, 3rd pair joins in series, then 4th pair ???

Just don't want to present a 2 Ohm load to a Yamaha receiver and burn it up. It won't be played loudly except when housecleaning!

[dodger]

What is the length to the office?

Before I answered, I tried a Google Search and I did notice one that will build custom for not much more.

Or you could hook the A speakers up and leave them on, switching only for 2, 3 or both. The specs should answer that question.

Or if I remember some Dahlquists, they plug into your AC power, as long as that is not detached, you should be fine.

dodger

EDIT:

Thinking of Active Crossover with a Sub.

End Edit

[Klewless]

I have one of those Niles speaker boxes with 4 speakers. I opened it up to see what is inside and what the "Protection" switch does.

You are correct in that every speaker turned ON, is simply added to the group. IOW all are parallel with each other.

But I would be willing to bet that the same thing is happening to your receiver/amp. You could even have, say, two Niles boxes on speakers A and B, engage both at the receiver along with all possible speakers and have one very low impedance. This is likely to send your receiver into never-never land.

The protection button inserts a resistor in series with the amp. Don't remember it's value but I think it was in the neighborhood of 2 ohms.

The formula for total resistance in parallel is:

1/R = 1/R1 + 1/R2 + ... + 1/Rn

As you can see the total impedance keeps getting smaller. So in theory eight 8 ohm speakers would become 1 ohm.

[colterphoto1]

yer right Klewless, all I had to do was look at the dern thing.

So if both the receiver and Niles Box just keep adding speakers in parallel, with three sets of 8 Ohm speakers (regardless of where they're patched in, Receiver A or B or Niles) ) , I'm at what like 2 Ohms, and if I push the PROTECTION button, I'm wiring a 2 Ohm resistor in series, bring the total back to around 4 Ohms. Is this right?

With that setup, would all three speakers be getting the same wattage (irrespective of line loss through speaker leads)? So if I've got a 100 watt per channel amp, at full peak, each speaker would be getting 33 +/- watts. Even if the Dahlquist are 'A' and everything else is on 'B' Niles circuit, there's no way to give the Dahlquist more power short of inserting another amp in the loop somewhere right?

Sorry to make this sound so complicated. Perhaps I should just let the Yamaha receiver service the office Dahlquist only, then send a line out to ANOTHER power amp - to the Niles box- to the network of ceiling and bedroom speakers. That gives more power from an amp that can take the load, without presenting a low imp load to my receiver. I could also use the rec out circuit so the whole house could have a different signal AND put an eq (got lots of spare 2x10 bands around) to taper off the low end (which is absent in these speakers anyway) and smooth the general response of the whole house system. I would also be able to blast in the office, with softer background music through the house. More equipment equals more flexibility, yes?

Any installers care to comment?

Michael

[dodger]

If you have a stereo receiver, speakers a and speakers b receive the same power.

When you add a - 8 ohms

+

b - 8 ohms you can total 4 ohms, thus the thought of more power.

If you have the Niles SS - 4:

plug in from A - make the DQ-10s the first switch - always in, that way you are always powered unless an active crossover has been added then there may be the AC factor as noted.

Unless there is an impedance or b section problem there should be the same power to each - A & B.

You can try by moving the DQ-10s to B, switch off A.

The variance would be if you had the SSVC-4. Then call 1-800-BUY-HIFI and ask for Tech support.

dodger

You can then add 3 more sets depending on the stability of the Yamaha. But with protection pushed in, you'd run at least 3.125 ohms

EDIT: NOT DAHLQUIST DQ-10s END EDIT

[Klewless]

The power amp will put out more as a function of the total impedance it sees.

However each speaker will take what it wants and if they are not identical, then one may consume more power than the other.

They each see the same voltage from the amp; the current (therefore power) does what it does individually.

[dodger]

----------------

On 2/24/2005 2:48:02 PM Klewless wrote:

The power amp will put out more as a function of the total impedance it sees.

However each speaker will take what it wants and if they are not identical, then one may consume more power than the other.

They each see the same voltage from the amp; the current (therefore power) does what it does individually.

----------------

Correct, but a 100 watt amplifier should put the same amount out if only one pair is hooked to A or they are hooked to B and A shut off. The unused set A or B is always shut off in proper human control.

My point was:

ONE pair of speakers

Speaker Output A: Power out

Speaker Output B: Power out.

From reading closely what ColterPhoto1 wrote, the implication was that Output A has a Higher output than does Speaker Output B.

EDIT: error, not DQ-10sEND EDIT

Thus he connects his Dahlquist DQ-10s to Speaker Output A,

- taking no other speakers in at this point - A will be louder than if he switched off A and connected the Dahlquists to Speaker output Terminals B.

That should not be the case A should not be louder than B - with only the Dahlquists, moving them from A to B, switching off A.

Now if I take my Cornwall IIs, put them on Speaker Output A,

Then connect my Heresys to Speaker Output Terminals B, (L and R in all cases) and switch both on, the volume of the Cornwall IIs drops.

Though both the same Nominal Ohm Rating, the Heresy is less Efficient.

EDIT: Klewless and I are both correct - noting the same value and efficiency of the sets of speakers.

But if he utilizes the Niles on Speaker output A, connects his Dahlquist to Speaker output 1, switches on the protection circuit, which will drop to the 3.125 ohms, protection circuit.

When noting a Speaker Impedance, it is a nominal figure. At some Frequencies it may be 6 ohms or 9 ohms.

We are straying from the original post. I do not advocate a second Niles on Output B. But though he posted that he would like at some time to possibly add more speakers, but the Dahlquists need to be on, why not for now just use the Niles on A with the Dahlquists switched on and the protection switched on.

The question though does become whether the Yamaha can handle a 3.125 ohm resistance.

The 1-800-BUY-HIFI, Tech Department is Niles. As posted before.

EDIT: THERE ARE OTHER NILES< NHT UNITS WHICH WILL ALLOW MORE SPEAKERS> END EDIT

I do not know off-hand the 800 number for Yamaha, but there should be a warning regarding lowest Ohms acceptable.

I am working with the parameters and question(s) posted, guided by my knowledge, my texts, a call to Niles also.

dodger