I have a powered sub to go with my HT 5.1 system. I also have a small 6LU8 tube amp for my turntable and streaming. I also have two sets of speakers, both are 89db sensitivity, so the 3 watt or so amp needs a little low frequency help.
Anyway, the HT amp is hooked up to the sub with the amps sub out. Since the tube amp does not have a sub out, I would need to use the speaker level inputs on the sub. My question is this, will connecting both of these inputs work? I typically use only one amp at a time.
Roger
Anyway, the HT amp is hooked up to the sub with the amps sub out. Since the tube amp does not have a sub out, I would need to use the speaker level inputs on the sub. My question is this, will connecting both of these inputs work? I typically use only one amp at a time.
Roger
The question is about using the powered sub line level input connected from one amp while the sub's speaker level input is connected to another amp that may not necessarily be used at the same time.
I've had no luck finding out what the result would be of simultaneously connecting a powered subwoofer to two different amplifiers by using its low-level connection for one and its high-level connection for the other.
I can give your thread a bump though!
Perhaps stating the make and model of your subwoofer would be of help.
I can give your thread a bump though!
Perhaps stating the make and model of your subwoofer would be of help.
I believe that, if working, they must be forcedly used one at a time.
However, as far as I know "SW" output usually is just a preamp line out (RCA socket).
I'm not an expert, but in my opinion it also depends on the characteristics of the active subwoofer.
Does your subwoofer have 2 low level line-in inputs (L/R)?
The amp SW output is a single output that goes to one of them?
Also does it have 2+2 pairs (L/R) of high level (speakers) inputs and outputs?
If so, it should be doble using necessarily one amp at a time, otherwise unpredictable results if not damages.
You can find some related replies here too, but I haven't deepened them.
Anyway, I just noticed the first one is a Bot reply (which I wouldn't trust too much).
@Logon
It reads like Roger's HT amp has an LFE output. If so, the subwoofer could have an LFE input (a single RCA connection) and/or two RCA line level inputs, as well as high-level speaker inputs.
I cannot rule out the possibility that having both amplifiers hooked up and potentially working at the same time could have some sort of deleterious effect.
Under the circumstances, I therefore agree with your advice to have only one amp connected at any time.
What we need is for a subwoofer expert to chime in and educate us. I wonder in which forum they are hiding? 🙂
It reads like Roger's HT amp has an LFE output. If so, the subwoofer could have an LFE input (a single RCA connection) and/or two RCA line level inputs, as well as high-level speaker inputs.
I cannot rule out the possibility that having both amplifiers hooked up and potentially working at the same time could have some sort of deleterious effect.
Under the circumstances, I therefore agree with your advice to have only one amp connected at any time.
What we need is for a subwoofer expert to chime in and educate us. I wonder in which forum they are hiding? 🙂
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Yes, I realize your point of view, but still I'm not sure about that since the subwoofer is active and we don't know its model, circuitry or functions, so it probably would take a guessing anyway.
Frankly, if the amps will be used one at the time I can't see an issue.
Maybe a problem could arise if both of them were to be turned on by mistake.
I've an active subwoofer in my PC system and in its manual it says not to use the two inputs (high and low level) together.
Yet it refers to the use of a single amplifier...
Yes, the information I've found always relates to a single amplifier using both the low and high level inputs.
Using both from a single amplifier is said to confuse the electronic wizardry inside the sub and mess up the sound.
We don't know how the sub isolates the low and high level inputs so there is always the possibility of an interaction if two amps were to be used.
The advice to Roger stands - be sure to use only one amp at a time.
Using both from a single amplifier is said to confuse the electronic wizardry inside the sub and mess up the sound.
We don't know how the sub isolates the low and high level inputs so there is always the possibility of an interaction if two amps were to be used.
The advice to Roger stands - be sure to use only one amp at a time.
Exactly, and if it is true that it happens for a single amp then that same behavior certainly can't be different if it's related to use of 2 amps. 😉
Of course the interaction will occurs for sure in any case, since the amplifier inside the subwoofer is obviously not designed to work that way.
But if one of the 2 amps is turned-off then they can't interfere. 🙂
If you think of a sub as pre and power, the power has to be happy with what the pre can provide. The high level is too much for it. It needs reducing, to allow it's use of a power stage with such input expectations. Thus, the chain logically goes high level, to low level, to power. I have a sub here, where what you input as high level, appears on the phono jacks of the low level, at low level. As it passes by on it's way to the power amp stage.
My concern is how well separated the high level and low level stages are. Only because it's valves though, and I know nothing about valves. If they have a low impedance they might drain the HT signal. Which seems less likely, if they are turned off.
I would probably just get on with it. There is always a chance it might go badly, but there is nothing really there, that could damage the other. Presuming the high level is more than just a voltage divider, and at least has some coupling capacitors.
My concern is how well separated the high level and low level stages are. Only because it's valves though, and I know nothing about valves. If they have a low impedance they might drain the HT signal. Which seems less likely, if they are turned off.
I would probably just get on with it. There is always a chance it might go badly, but there is nothing really there, that could damage the other. Presuming the high level is more than just a voltage divider, and at least has some coupling capacitors.
Thanks guys. The picture is similar to mine, I am just not close to it right now, but features look familiar.
My typical usage as HT, the second amp is always off. In the case of using the second amp,when playing vinyl, the HT amp is off.
So far,so good. The potential issue is when I stream Pandora. I Need the HT amp on to view/select on the TV. I turn the volume on the HT system down and mute but the amp is still on.
Also should parallel the speaker connections or serial?
Roger
My typical usage as HT, the second amp is always off. In the case of using the second amp,when playing vinyl, the HT amp is off.
So far,so good. The potential issue is when I stream Pandora. I Need the HT amp on to view/select on the TV. I turn the volume on the HT system down and mute but the amp is still on.
Also should parallel the speaker connections or serial?
Roger
Please give more information regarding the above question.
Does that mean you've actually had both amps switched on while each is connected to the sub, and nothing has gone awry?
You could make a switch box to switch between the 2 inputs, however you would probably need to set the xo on the sub for the valve amp, which may be a different setting to the one you use for the AV amp.
Rob
Rob
Do I run two sets of wires, one to speaker and one to sub (parallel) or to the in/out on the sub and then on to the speakers (serial).
To be safe, my suggestion is using a Niles SAS-1 switcher.
Niles SAS-1 Installation Manual
You can still find an used unit at low prices.
Niles SAS-1 Installation Manual
You can still find an used unit at low prices.