My Wilson Alexx V speakers are rated +/- 3db 20Hz-32kHz thus I always dismissed the need for subs. At the same time I never felt my soundstage depth and room filling “richness/fullness” was where it should be. After extensive research I concluded a pair of subs might address this issue. I own a pair of SVS SB-17-Ultra R and Perlisten D212s used in other systems. I decided to try REL who has a reputation for two channel audio subs and high-level inputs as the recommended connection. Purchased a pair of REF No. 31s and installed to the outside of my speakers. Low pass set at 27, phase180 and 1/3 loudness (13) . My goals were realized; bigger scale, hall ambience, image density and ease at all volumes. Highly recommended.
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Very cool! Always more to figure out. How are you feeding the REL subwoofers?
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Hi Daniel, I’m using the REL Baseline Blue with the Neutrik Speakon High-Level interconnect with both red and yellow leads connected to the speaker positive terminal and the black ground connection floated. I got lucky as there is no ground loop hum. Cheers
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Excellent! That’s what I was hoping to hear.
@skinzy running dual #31’s with my Forza, I have been a dual REL sub person for years and I can’t imagine ever going back
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I guess there is a SQ benefit from using two of these to drive my JL Audio Fathom F113v2 subs from my Mono Blocks rather than using their internal Amps driven by the second set of XLR outputs from my PreAmp?
Is that a correct assumption?
I think you are not understanding high-level input. The subs (No. 31s) internal amp is being driven by the signal from the power amp but it is drawing a minuscule amount of wattage. These are 100% analog subs unlike the JL Audio which uses DSP. This means a low level connection is made from the preamp and then converted to digital for signal processing. If you like the control of DSP this is the preferred connection. This is how I understand the context.
I understand that active subs need a line level input. Either from a PreAmp or from the Sub adapters.
What I don’t understand is the benefit, or more precisely, the cost v benefit, of taking an amplified signal at my speakers, reducing its voltage to line level and feeding an active sub versus taking the line level output direct from a PreAmp.
For me, I have the PreAmp outputs and the XLR cables to connect to my subs. To use the MSB Sub adapters, I would need to spend ~$6,000.
I am assessing that value equation.
In your situation I understand your question better. Would MSB Sub adapters improve the SQ of your JL Audio’s. I can’t answer that. I do know that the “marketing” feature of the REL subs is that they are driven by the SQ of the power amps in the same way that the main speakers are. Plus there is no DSP and digital conversion.
Very dependant on the PreAmp and the Sub, but the goal is to eliminate any noise from entering the system before the amplifier. Injecting, even low level noise, and then amplifying it to your speaker is what we are trying to avoid. Grabbing the signal post amplification is ideal.
Powered subwoofers typically have very noisy amplification, because it has very little effect on the performance vs say revealing tweeters. So, connecting any powered sub to the low level signals can be a recipe for losing so much detail and “background blackness”.
Our Sub Adaptors are ideal, since they have great isolation and are passive. But any solution that takes the amplified high-level signal is a good starting point.
It might at least be worth comparing the difference with a demo set. That is why we made them! Certainly not to make us any kind of money… it’s a niche of a niche type of product. We just want every MSB system to sound its best!
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Thanks Daniel! As always, a very reasonable, science based perspective. Craig