[L2fly]

FYI, I am a newbie at all this.. for example, just in the past week, I've learned what what an ohm IS (sort of!)


I'm trying to set up a speaker system for a long patio (about 40 X 12) with a Sherwood RX-5502 amp/receiver, 100 W X2, that will run A, B, C, D speakers, and three pairs of TIC ASP120 speakers 50/100 W, 8 ohm.


I want to have two different 'areas' of sound, and able to be turned on or off, on the patio... directly above the spa (about 10 X 10) and the remaining patio area (30 X 12). I'll be running the amp out of the bedroom, about 5 ft to the outside wall, and have runs from 15 - 40 ft. I plan on using 14 g wire.


I've decided I need a total of three pairs of speakers to get what I want done... one pair right above the spa, on 'A', and four speakers around the remaining patio area.


My issue:


I noted in the owners manual for the amp, that it says

Quote:
For safe amplifier operation, use the

speakers with impedance of over 8Ω when

you connect a pair terminals of SPEAKER A

and B terminals or/and a pair terminals of

SPEAKER C and D terminals and use the

speakers with impedance of over 16Ω when

you connect both SPEAKER A and B

terminals or/and both SPEAKER C and D

terminals.

Reading this is ridiculous... "or/and" what???

Nearest I can figure, this means that on this amp, the speakers 'A/B/C/D' run in parallel, so if you play A and B, with a pairs of 8 ohm speakers on each (like the TICs), you'll get a total impedance of 4 ohms, and risk the receiver overheating...


My questions:


1. Am I even reading this right?? If I have a pair of speakers on A, and a pair on B, will I be running at 4 ohms, and overheat my amp? How about A and C? (It has a 'Room 2' feature, that seems to let you adjust volume on AB and CD separately, and I'm not sure if this means AB and CD don't share impedance loads or not... )


2. If I do wire up a pair of speakers on A and B, and play A and B at the same time, and it gives me a 4 ohm impedance, if I keep the volume down, will that reduce the risk of frying my amp? How big is this risk, anyway? How about if I run A, B, and C at the same time, a pair on each?


3. An option I've been seriously considering is running two speakers on the right channel, and two on the left, in series, on the 'B' speaker selection, around the patio seating area, giving me four speakers total, keeping the pair above the spa on 'A'. I understand this will increase my ohms to 16, but from what I've read, this is not a huge deal as the amp runs at 8ohms, and from what I understand running an 8 ohm amp through 16 ohms is better than the other way around... but I'm wondering if the greater impedance will lesson the sound the speakers produce?



And I'm also concerned that the wattage loss may make sound suffer, as I'm not sure if the 100 W X 2 means 100 W per left channel, and 100 W per right, or 50 each... if 100 right and 100 left, seems like 50 to each of the two speakers should be fine... yes?


Anything else I need to worry about running two speakers in a series?



THANK YOU for any help you can give me... I've been doing google searches for the last week trying to figure it out, and it keeps directing me here, so I finally decided to register and ask my questions directly!

 

[Class A]

Check out a Niles speaker selector box. It contains a protection device to keep your AVR from overloading. I set one up at my cousins house 10 yrs ago w/ceiling speakers in 4 rooms plus the porch and the pool area. It's run w/out a hitch for the entire 10 yrs. Crutchfield sells these units. Should solve your problem.

 

[L2fly]



Quote:
Originally Posted by Class A /forum/post/20854443


Check out a Niles speaker selector box. It contains a protection device to keep your AVR from overloading. I set one up at my cousins house 10 yrs ago w/ceiling speakers in 4 rooms plus the porch and the pool area. It's run w/out a hitch for the entire 10 yrs. Crutchfield sells these units. Should solve your problem.

Thank you for the reply! I'll definitely be looking into upgrading in a few years... for the time being, I've got to work with what I have, as my oven just went out, so I need a new one, my student loans are due, yadda, yadda, yadda...

I did call Sherwood and clarify that the A/B speaker selectors run on the same circuit, so, when running A/B together (or C/D together) its like running the speakers in parellel... I can run A/C at the same time, though, and as they are on different circuits, I'll not have a potential over heating problem. Which is likely what I will do, run two zones in the patio seating area, A/C, and leave B over the spa.


But, I'm still curious about running speakers in series, and tempted to try running four 8 ohm speakers on the B circuit, two on the right channel and two on the left, for all over patio sound... figure this would give me a little wiggle room if I ever wanted to play A/B together, with A over the spa, as A would then = 8 ohm, B = 16 ohm, then together they would be approximately 5.83 ohms (calculation found on another website!)


Curious if there are any inherent problems with running two speakers in a series? Or problems with running two speaker sets with different ohms impedances in parellel? (8ohm & 16 ohm, as explained above)


I'm certainly making this way to complicated, and probably could resolve things with a $100 speaker selector box, but I'm stubborn... and am enjoying learning about this stuff!!

 

[Scout's staff]

X2 on the impedance matching speaker selector. They are cheaper than having to replace a receiver or speaker due to user error

 

[L2fly]

Yes, you're probably right... my cheapness/stubborness/curiousity has cost me plenty over the years!