Electrical question

[Richard]

ok... out of my ignorance, I will probably ask the question poorly but I shall try.

We've started finishing our basement and this is where I'll end up moving my stereo & home theater stuff.

I have a 150 (but it might be 200) service box in the house and it happens to be located in the room I'll put the stereo in.

I'm WANTING to put some dedicated circuits and outlets in the room that will ONLY have stereo stuff on them.

I'm using speakers that are about 109 db so I want to avoid as much noise, cross noise and ground loops as I can.

I was thinking on adding a second panel and running a dedicated 12g line to various places where I might have a power amp (several tube amps) I might even go as far as to run TWO lines to a specific outlet and breaking the connection between the outlets so each half has a dedicated line.

Point being... I'm more in favor of over kill than underkill and later, needing to use those power strips. Or, if I ever DO need a power strip, I want the OTHER plug on same outlet to have it's own source.

Ok... so now to go with the above... I'm told I can get some kind of isolation transformer or something, where these outlets might have a slightly less net rating however, they WILL be isolated from all the lights, motors, hum of the household??

if so, what, where how do I find out more about these??

 

[woodlot]

I might even go as far as to run TWO lines to a specific outlet and breaking the connection between the outlets so each half has a dedicated line.

I'd skip that. If you want two dedicated circuts the thing to do whould be to install two seprate j-boxes, each supplied by a seprate breaker.

You can do what you propose but it does create a saftey hazzard. Imagine flipping off the breaker to the top recepticle and assuming that power to the entire j-box was gone. ZAP!

You can do it safely buy using a two-pole breaker that has the handles tied together (like what you'd use when running a 220 circut) that way whenever one circut is cut the other one will be too. You could probibly share a neutral by doing it this way too, buy I'd opt for the two j-box idea.

As far as filters go, I'm cluless. I'm no audiophile!

 

[Kendall69]

Filter Isolators, ac power line Equipment Interaction, isolation transformers, voltage regulaters

 

[Richard]

Woodlot, you bring up an excellent point about being zapped on the other 'half' of the outlet I'd never thought of that.

Just for the record, my bro in law is an electrician and I'll probably hire him out to do the proper connections but I'll be the one to do the actual grunt work of pulling the wires to various places.

I just didn't want anyone to conclude that I was planning on doing this myself.

 

[Steve_Miller]

You can do what you propose but it does create a safety hazard. Imagine flipping off the breaker to the top receptacle and assuming that power to the entire j-box was gone. ZAP!

I thought the code stated that a split plug has to have a double breaker so this occurrence doesn't happen.

As far as running dedicated lines to cut down on interference, it will do very little to stop it if the noise is on the power source. you would be better off with a true sine wave UPS. They take the incoming power and reproduce the sine wave for the output power using inverter technology thus eliminating the incoming noise. You have to research this quite well as some inverters are not true sine wave outputs.

Steve

 

[_RaT_]

ok... out of my ignorance, I will probably ask the question poorly but I shall try.

I'm using speakers that are about 109 db so I want to avoid as much noise, cross noise and ground loops as I can.

I'm curious what this statement means and why it is significant. I should think a speaker that has less efficiency would exacerbate the problem (if you have one). Regardless, running an isolated ground back to the main panel is about the only way I see of attempting to eliminate what may be a problem. I have never experienced so my opinion has little basis other then whenever we wire commercial electronics, we always use isolated ground plugs and carry the ground past the subpanel to the main.

 

[Soundguy]

While you can order 1:1 iso xformers.. i think you are going a little overkill.

Get a good power conditioner.. like from APC.. the Line-R seires.. it has good emi/rfi filtering, voltage stabilization, correction, and spike protection.

If you have a line with a hum.. use a 'hum buster' (tm) it's essentially a 1:1 audio iso xformer...

I have thousands of watts of amps and other rack and stage gear running on a few circuits with the only consideration of as load level..(not what components are on them) multiple venue's like this....

Soundguy

ok... out of my ignorance, I will probably ask the question poorly but I shall try.

We've started finishing our basement and this is where I'll end up moving my stereo & home theater stuff.

I have a 150 (but it might be 200) service box in the house and it happens to be located in the room I'll put the stereo in.

I'm WANTING to put some dedicated circuits and outlets in the room that will ONLY have stereo stuff on them.

I'm using speakers that are about 109 db so I want to avoid as much noise, cross noise and ground loops as I can.

I was thinking on adding a second panel and running a dedicated 12g line to various places where I might have a power amp (several tube amps) I might even go as far as to run TWO lines to a specific outlet and breaking the connection between the outlets so each half has a dedicated line.

Point being... I'm more in favor of over kill than underkill and later, needing to use those power strips. Or, if I ever DO need a power strip, I want the OTHER plug on same outlet to have it's own source.

Ok... so now to go with the above... I'm told I can get some kind of isolation transformer or something, where these outlets might have a slightly less net rating however, they WILL be isolated from all the lights, motors, hum of the household??

if so, what, where how do I find out more about these??

 

[Richard]

Thanks for the comments guys.

Rat, you said “I'm curious what this statement means and why it is significant. I should think a speaker that has less efficiency would exacerbate the problem (if you have one).”

I will admit I do not yet know if I have any problem here. What I’m trying to do is help guarantee that I DON’T have a problem, even if I’m tossing some money into the wind. As for speaker efficiency, do I understand you right? You are thinking a LESS efficient speaker would reveal MORE of a line noise problem? If so, I’d suggest you are flipping something backwards. My understanding is the higher you go in efficiency (or is it sensitivity?) the more revealing the speaker might be to extraneous noise and the more important it becomes to have QUIET components in the food chain. Perhaps I’ve got it backwards?

Soundguy: I also think it might be a bit of overkill but I’d rather do an ounce of prevention than a pound of cure since I won’t “know” if I have a problem until the room is done and I don’t want to kick myself later for not addressing this potential issue. I’m going to look into your APC’s however, will they be rated to take some 100 watt tube amps? I was told by someone that plug into the wall isolators won’t have the current needed to run hot tubes like that?

 

[_RaT_]

Thanks for the comments guys.

Rat, you said “I'm curious what this statement means and why it is significant. I should think a speaker that has less efficiency would exacerbate the problem (if you have one).”

I will admit I do not yet know if I have any problem here. What I’m trying to do is help guarantee that I DON’T have a problem, even if I’m tossing some money into the wind. As for speaker efficiency, do I understand you right? You are thinking a LESS efficient speaker would reveal MORE of a line noise problem? If so, I’d suggest you are flipping something backwards. My understanding is the higher you go in efficiency (or is it sensitivity?) the more revealing the speaker might be to extraneous noise and the more important it becomes to have QUIET components in the food chain. Perhaps I’ve got it backwards?

Soundguy: I also think it might be a bit of overkill but I’d rather do an ounce of prevention than a pound of cure since I won’t “know” if I have a problem until the room is done and I don’t want to kick myself later for not addressing this potential issue. I’m going to look into your APC’s however, will they be rated to take some 100 watt tube amps? I was told by someone that plug into the wall isolators won’t have the current needed to run hot tubes like that?

Richard, I was thinking that as you turned an amplifier up to increase the volume, which you would do with a less effiient speaker to get a similar sound level as a more efficient one such as yours, you would also be increasing any hum by the same amount. Since THD typically increases with an increase in output, I would think you would therefore be exacerbating the problem by amplifying the noise or any interference induced or directly placed on the 120V line.

 

[Soundguy]

I got a 900w and a 1200w setting on my desk right now....how big you need?

What's is full input load say on the lil sticker on the back?

Soundguy

Thanks for the comments guys.

Rat, you said “I'm curious what this statement means and why it is significant. I should think a speaker that has less efficiency would exacerbate the problem (if you have one).”

I will admit I do not yet know if I have any problem here. What I’m trying to do is help guarantee that I DON’T have a problem, even if I’m tossing some money into the wind. As for speaker efficiency, do I understand you right? You are thinking a LESS efficient speaker would reveal MORE of a line noise problem? If so, I’d suggest you are flipping something backwards. My understanding is the higher you go in efficiency (or is it sensitivity?) the more revealing the speaker might be to extraneous noise and the more important it becomes to have QUIET components in the food chain. Perhaps I’ve got it backwards?

Soundguy: I also think it might be a bit of overkill but I’d rather do an ounce of prevention than a pound of cure since I won’t “know” if I have a problem until the room is done and I don’t want to kick myself later for not addressing this potential issue. I’m going to look into your APC’s however, will they be rated to take some 100 watt tube amps? I was told by someone that plug into the wall isolators won’t have the current needed to run hot tubes like that?