Sub with floorstanders--opinions...

Discussion in 'Speakers' started by DAA, Jun 16, 2017.

  1. DAA

    DAA New Member

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    So, I just took home a mint Boston VR500 sub for $20. Want to pair it with my Boston T830s lcrossed over at 40hz for music only. Now, I use a Sony TA700 ES integrated. Hook up options are limited---speaker level and out to mains or Towers A and Sub B. Sony does have an Adaptor switch, but I'm but I'm not sure that's a true pre-out. Is it!?! I like to run the amp direct---sounds great. Opinions welcomed...thx!
     
  2. swechsler

    swechsler Frog Whisperer

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    The BA sub has speaker-level inputs. I'd use those. I would also run the towers directly from the amp rather than through the sub's built-in crossover, since the high pass crossover frequency is probably higher than you'd want with those towers. Adjust the low pass frequency on the sub to match the towers' natural low frequency cutoff (which is probably pretty low).

    The adapter I/O is most likely at a fixed level, otherwise it would be labelled preamp level in/out.
     
  3. onplane

    onplane What! No Wake???

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    DAA, with those speakers and your new (to you anyhow) VR500, I would recommend you hook the sub up using speaker B outputs on your Sony. I looked up your Sony and it puts speakers in parallel, so this will work and allow you to easily listen with or without the sub.

    In short, you gain ... flexibility.

    As for using the sub's speaker level outputs, I'd NOT do that. The sub's internal high pass filter is factory set at 100Hz and while OK for those little satellite speakers, it's just way too high for your towers.

    In short, you want the sub to fill in at the very lowest frequencies. With those towers you don't want the sub to take full responsibility for all low frequencies. Finally, that B speaker switch will help you dial everything in.

    Regards,
    Jerry
     
    Last edited: Jun 16, 2017
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  4. canuckaudiog

    canuckaudiog On a quest for high fidelity

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    Using the high level inputs (speaker inputs) on the subwoofer is the most recommended way to wire a subwoofer in. Why? Because it will receive the exact same signal your speakers do. This is how REL and other high end subwoofer manufacturers recommend subwoofers be wired in.
     
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  5. DAA

    DAA New Member

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    Thanks guys. I was considering running two lines from the A speakers as the sub really won't be a load. This way I can still run the amp in direct mode. Seems to not run that way when switched to A/B speakers. Make sense??
     
  6. onplane

    onplane What! No Wake???

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    Whether you run separate lines to the sub from A speakers or those same lines from B speakers, makes no difference to the amp. The amp will see exactly the same load in either case. Difference is primarily flexibility. B gives you the option to shut down the sub at the amp rather than having to turn the sub off.

    As long as you are not using B for an additional set of speakers, using B for your sub gains you flexibility with no difference to the amp.

    Not sure what you mean by "direct mode", but if you mean powering just the T830's without the sub, then the answer is... yes.

    In closing I agree with canuckaudio on speaker level inputs for music and for exactly the reasons he stated.

    On home theater systems, I prefer the lfe outputs.

    Regards,
    Jerry
     
  7. SaturationPt

    SaturationPt AK Subscriber Subscriber

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    Location:
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    I would run through the subwoofer's crossover (high-level in from amp, high-level out to speakers). This is tricky, and if you don't have a good subwoofer or the proper match, it won't work no matter how you hook them up. I've tried several subs for music, it took a lot of trial-and error to match it all up, but compounding the same frequency bass from two sources never works.

    Your towers are fine below 100hz this is true, but if you don't cross them out where you're crossing the sub in you will get an artificial hump in the frequency range where both speakers are producing music (and possibly a dip where they are out of phase). This is fine for theater, too much bass can be good for some, but it will not be accurate music.
     
  8. swechsler

    swechsler Frog Whisperer

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    The sub has both crossover frequency and level adjustments. Using these he should be able to adjust the low pass frequency of the subwoofer to a pretty good match of the main speakers' natural cutoff.
     
  9. canuckaudiog

    canuckaudiog On a quest for high fidelity

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    Running the speakers full range is the right way to do it. It doesn't produce extra bass, it simply helps even out the bass response. This is why subwoofers have volume controls as well so you can get everything properly balanced.
     
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  10. SaturationPt

    SaturationPt AK Subscriber Subscriber

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    Location:
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    But it does produce extra bass.

    A full-range speaker doesn't have flat response below its spec, but it does have response. Your woofer will be moving with a 10hz signal, even DC if it's sent down the wire to the speaker.

    If your subwoofer is crossed at 40hz, it will produce very little if any above 40hz, but from 40hz down the subwoofer and the main speakers are producing sound. Whether these sound waves coming from separate positions are in phase or not, will depend on many things including room acoustics and positioning. If you turn down the gain on the subwoofer so that you don't hear it you are defeating the purpose of having a subwoofer to some extent. You do not want the sub and main speakers competing.

    You like the way your speakers sound compounding and/or cancelling below 40Hz? Nothing wrong with that, and the OP might like it also. My point is simply to point out how that isn't going to create a flat response curve, nor anything close. My suggestion is still to go speaker A out to sub high-level, sub out to main speakers. If the sub has a good crossover in it this should be the best result without buying additional equipment.

    Another option would be to add a DSP, go preamp into DSP, use the DSP for your crossover, high-pass out to your main amp and main speakers, low-pass out to your subwoofer low-level in. This will allow you to tailor your crossover point and type to give you the most seamless transition between main and sub. You can buy a mini-DSP for around $100 and it will give you much flexibility.

    Easy answer is: try it both ways, through the sub's internal crossover and with the two compounding below your crossover frequency. Neither one costs you anything but wire at this point, and you might find that you like it. Be aware that speaker (and especially subwoofer) placement will drastically affect sound levels, putting the sub in a corner will give you a lot more bass than out in the room, on the floor more than up off of the floor, etc. The bass isn't directional so placement isn't important for imaging, but putting it too far from the main speakers will affect the balance. Also, many subs have a phasing switch, try it inverted and normal to see which gives you more bass.
     
  11. DAA

    DAA New Member

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    So, I'm up and running. Ran the speakers and sub off the A speakers. Crossed at 50hz as the main speakers are -3 at 40hz (and I think they play even a bit lower). Sounds pretty damn good. Sub is just barely there until a really low note hits. This is a pretty nice sub for music as it's not tubby sounding.
     
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  12. canuckaudiog

    canuckaudiog On a quest for high fidelity

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    I based my answer off of measurements I've taken of in room response. It's also general consensus that you want to run the speakers full range. It's similar to distributed bass systems. More sources of low frequencies throughout the room is better.
     
  13. WaynerN

    WaynerN Super Member

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    I like my REL sub because it gets it signal directly from the amp's speaker terminals. The input load is around 150K ohm, so it really has no interference with the speaker impedance on the amp. In doing things this way, the tower speakers are not crossed over all at, rather running at their full range. Then its easy to dial in the sub and have it go down to where the towers can't reach.
     
    Last edited: Jun 19, 2017
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  14. DAA

    DAA New Member

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    Yes. This is basically what I did and it seems to be working well!
     
  15. DAA

    DAA New Member

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    So, I'm super happy with this setup!! Sounds fantastic and sub integrates wonderfully just filling in lowest octave.

    Total cost of speakers and sub, including upgrades/foam: $90!
     

    Attached Files:

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  16. WaynerN

    WaynerN Super Member

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    Isn't it great to be happy with a system without mortgaging the house on it! I'm all about "bang for the buck" speakers, whether bookshelf or modest tower.
     

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