Adding a sub to a stereo setup?

[GeoffP.]

Hi Guys,

Just wanting to know if it's possible to add my SVS PB200 sub to a Naim 5si amp which I'll be taking delivery of next week?

Thanks Geoff.

[A9X]

You can do it one of two ways.

Poorly: run the sub in parallel with the L/R. Easiest and simplest, but may not be simplest to set up well.

Well: Add a line level xover before the Naim to high pass the L/R, adding the sub as an extra "way" to the system.

 

A long time ago I had Linn/Naim active system so it's not like option 2 is unheard of.

 

Setting up by ear alone is much more difficult than measuring and almost always produces lesser results.

 

 

[Wimbo]

38 minutes ago, A9X said:

Setting up by ear alone is much more difficult than measuring and almost always produces lesser results.

Please explain.

[A9X]

41 minutes ago, Wimbo said:

Please explain.

It's pretty obvious.

[Irek]

1 hour ago, Wimbo said:

Please explain.

He's saying that setting it properly might take few days or weeks + a little bit of patience. 

Look up SVS website.

 

'The crossover frequency of your subwoofer is the frequency at which your speakers start to roll off and your subwoofer kicks in with LFEs and bass notes. Most modern AV receivers feature an auto EQ program that will assign the proper crossover frequency automatically based on the capabilities of your loudspeakers. It’s generally best to leave these settings where they are.

If you’re using an AV processor, preamplifier or a DSP subwoofer to adjust the crossover frequency in a two-channel or surround sound set-up, here’s a few tips to get the best performance possible. As with any bass management functions, it’s helps to do some critical listening and experimentation to achieve the best sounding results.

• If you know your speaker’s frequency range, set the crossover point roughly 10 Hz above the lowest frequency your speakers can handle cleanly
• The most common crossover frequency recommended (and the THX standard) is 80 Hz.
• The numbers below highlight general guidelines for speaker/subwoofer crossover frequencies
  • On-wall or Tiny 'satellite' speakers: 150-200 Hz.
  • Small center, surround, bookshelf: 100-120 Hz.
  • Mid-size center, surround, bookshelf: 80-100 Hz.
  • Large center, surround and bookshelf: 60-80 Hz.
  • Very large center, surround, bookshelf: 40-60 Hz.
  • Tower speakers with 4”-6” woofers: 60 Hz.
  • Tower speakers with 8”-10” woofers: 40 Hz or Large/Full-Band (i.e., full-range).
• If you’re unsure about your speaker’s ideal crossover frequency, try our SVS Subwoofer Matching Tool, which will recommend the ideal SVS subwoofer for your speakers and tell you the best crossover frequency.
• Listen for a smooth transition between speakers and subwoofer. Ideally, the blending will be so seamless, you won’t be able to localize the bass and everything will play in unison.
• If you’re noticing a bass bump at the crossover frequency, try adjusting the volume control to match the output of your main speakers.
• For a deeper dive into crossover frequencies, check out our Digital Bass Management Primer. "

[almikel]

2 hours ago, A9X said:

Setting up by ear alone is much more difficult than measuring and almost always produces lesser results.

 

1 hour ago, Wimbo said:

Please explain.

I agree with @A9X, setting up a sub by ear is not the best approach - measurements will provide the ability to compare results across different sub/speaker/listening positions to achieve the smoothest bass at the listening position.

 

The brain's "audio memory" is extremely short - by the time you've shifted a sub and listened again, your brain has a poor recollection of what the bass was like with the sub in the previous position...better to have measured the sub response...

 

...better still do the "sub crawl" - put the sub at the listening position (literally where your ears would be), and measure with the mic at all the positions likely for the sub - compare the measurements and place the sub at the spot where the mic showed the smoothest bass at the listening position.

 

cheers

Mike

[A9X]

12 minutes ago, Irek said:

He's saying that

You've made some incorrect assumptions...

12 minutes ago, Irek said:

setting it properly might take few days or weeks + a little bit of patience.

It won't take anywhere near that long.

13 minutes ago, almikel said:

I agree with @A9X, setting up a sub by ear is not the best approach - measurements will provide the ability to compare results across different sub/speaker/listening positions to achieve the smoothest bass at the listening position.

 

The brain's "audio memory" is extremely short - by the time you've shifted a sub and listened again, your brain has a poor recollection of what the bass was like with the sub in the previous position...better to have measured the sub response...

Bingo.

 

Plus to expand, human hearing is weakest, both in terms of sensitivity and resolution at LF. It's also easy to miss narrow peaks or dips in the FR, which are hard to detect by ear, but over time you may wonder why a particular recording or instrument on such, usually piano, organ or bass has a weak or exaggerated note or harmonics. Xover frequencies and slopes can more easily be chosen by the FR and distortion characteristics of the sub and L/R to see where they marry up best.

 

With a decent measurement suite, such as REW, a calibrated mic and a PC, I'll find those errors in minutes. As everyone has a PC, all it takes is a Umic (~$100 last I looked) to set it up. I'd rather pony up for the mic, and get it done in a couple of hours than spend weeks agonising over it by ear. Plus the mic can be useful for other tasks later. I've often offered to lend my measurement system out, but have never had a taker (can't any more as I also use the phantom PS and mixer for another task).

[A9X]

30 minutes ago, Irek said:

Look up SVS website.

I meant to add this into the previous post, but there is a considerable amount I disagree with in the SVS info you copy/pasted. I'd rather measure the sub and L/R and make decisions based on that than go by ROTs for example. They're trying to tell you how to add a sub without high passing the L/R as they have no facilities to do that on their subs. As I stated earlier, not the best approach.

[almikel]

45 minutes ago, A9X said:

They're trying to tell you how to add a sub without high passing the L/R as they have no facilities to do that on their subs. As I stated earlier, not the best approach.

agreed - good sub integration usually requires a high pass filter on the main speakers to 'crossover" to the sub.

 

there is an alternative if your mains are very capable in the low end to have an overlap rather than a crossover between mains and sub (essentially providing additional bass sources in the room), but this approach will only work if your mains can produce the low bass without distortion and you have measurement and EQ capability to smooth the room's bass response...I tried this approach for a while and went back to crossing over between mains and sub - the integration is easier.

 

cheers

Mike