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Using Krell rca & bal outputs for the same channel

Why would I do that?
My sub has a highpass filter above 65hz. The dedicated sub channel can have info above that. So how can I get the missing freqs above 65hz. I can get a second sub but I’d rather not.
Since Krell’s RCA & balanced outputs are active at the same time, I can send the sub channel to another speaker using a Y cable to get the missing info. I’m thinking if I must use a Y cable and overtax a speaker with sub info, I’d send it to a rear speaker.
Does anyone know if using both outputs will affect the sound? The manual says that both outputs are active but to connect using only one. Will there be impedance issues? I also have an Audyssey EQ between the PrePro and the amp, so I would use the Y cable from sub and one of the rear to the EQ’s rear channel which will turn the analog signal into digital for EQing and back to analog for the amp.
captaincapitalism
dave_b's avatar
dave_b
3,159 posts
 
Rcprince has it correct. Remember, a subwoofer is just that...a SUB woofer i.e..below normal bass frequencies.
captaincapitalism OP
52 posts
 
In music this is not an issue. The lfe does not get information above the crossover. My system crossover is 60hz.
However, if my processor doesn't create the LFE output like in music and if the LFE comes from an independent source other then existing channels then all bets are off. No 2+ channel PrePro in existence applies crossovers to the dedicated LFE channel.

In other words: Crossovers do not apply to the .1 channel.

If that is the case, then my sub gets the entire LFE channel. But my sub nitpicks on LFE freqs. This issue applies to any source that has a dedicated LFE.

Anyway, I am researching if Dolby and DTS mirrors the LFE in other channels. Since other channels also go down to 3hz, it would make sense that they would use LFE just for effects even though it is the other channels.
But I will be limited if someone has info in the LFE and no where else.
rwwear
2,866 posts
 
In my system, which is two channel, I use the RCA outs from my preamp to the sub. The sub's low pass filter is set at 50Hz. I use the balanced outs for my main speakers and they run full range. This works very well and there is no crossover to muck up the sound of my mains.
timrhu
2,779 posts
 
I did the exact same thing as Rwwear but had no preamp. The XLR outputs of the cdp were sent directly to the power amp while the rca outputs went to the sub. Both cdp outputs are variable so no preamp is needed. It was not difficult to get the sub adjusted to mate with the monitors using this configuration. You should have no problem going this route from the Krell preamp. Both the sub and the speakers are fed the full frequency spectrum with the sub crossover and level controls adjusted for a satisfactory blend.
captaincapitalism OP
52 posts
 
I use the balanced outs for my main speakers and they run full range. This works very well and there is no crossover to muck up the sound of my mains.
I am concerned about 2 issues:
1) To send my mains full bass because
a) Wearing and overtaxing my cones with low freqs, my Cremonas Mains go down to 32Hz.
b) Usins a Y cable in the audio chain for my mains. (I must use the Y because of my EQ that sits between the PrePro and the amps)
2) My EQ prefers a crossover and has alot of software dedicated to working with the crossover. I don't want to sacrifice the EQ's crossover optimization for my mains.

Based on the above preferences, I could simply use a rear speaker. Since in Dolby and DTS soundtracks, the rear speakers are used around 5% of the time. So it will be like I have 2 subs. Although it just occurred to me that I should use a Y cable going out as well. Since the EQ will be testing the LFE channel.
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