Are big subwoofers viable for 2 channel music?

How SVS fixed it...

I think it's a little disingenuous of SVS to imply that they're the only ones that know how to use a big driver.

Hello phusis and jwmorris,

     I think our disagreements and differences expressed on this thread can be boiled down to a difference in preferences and priorities. I could go into detail but I believe it basically comes down to both of your top priorities seeming to be the optimum bass extension of your sub systems for HT Bluray 4K Ultra HD audio performance and my top priority being the optimum bass quality of my sub system for 2-ch stereo music hi-res digital music file audio performance.  I think both are enjoyable and worthy goals.  But why can't we have both?

    It's my understanding that current direct to hi-res digital recording technology is capable of recording deep bass content below 20 Hz on both digital music files and 4K Ultra HD Bluray discs.  Given the factual limits of human hearing, of course, it would make little sense to record this deep bass as discrete stereo channels and the bass below 80 Hz would be summed to mono during the mixing stage for both music and HT audio recordings.  
     I think this would be a big step forward in the quality of the listening experiences involved with both music and HT audio.  This would just require consumers possessing high quality subs capable of reproducing such deep bass frequencies, including my upgrading my 4 subs to ones of higher quality capable of reproducing bass frequencies accurately down to single digits.  
     Of course this would probably also destroy most regular consumer subs and sound bars that couldn't handle single digit bass frequencies, but that's a reasonable sacrifice, right?

Tim 

@noble100  I agree the priorities of any system can be very different. The priorities of the person mixing the music or sound track also come into play. The bottom line is we each spend our time, and hard earned money where it matters to us most.  

The question of destroying consumer subs and sound bars is the entire reason behind the BEQ thread linked earlier. Someone discovered that some film companies were reducing low bass content in blu-rays and DVD to prevent damaging consumer equipment. 

That makes sense. But if you have invested the time and money to have a system capable of sub 20 Hz performance you can get that filtered information back using BEQ. 

I did not plan on having a system capable of ultra low frequencies. The sub-woofers I bought were available less than 30 minutes away. I thought it was a great opportunity to own a pair of world class sub-woofers, so I made the purchase. 

I do not believe I am lacking in quality or quantity. I have added some screen shots of my room measurements to my profile. I will try and add some pictures soon. The next thing on my wish list is some room treatments. 


@phusis Thank you!


John

       

Hello John,

    
      I've always built my systems based on the assumption that bass content on virtually all music and HT source material (LPs, CDs, SACDs, DVD and Bluray, digital files, etc.)  only had bass extension down to 20 Hz since any recorded bass below 20 Hz was generally filtered out at the mixing stage.  
     I've been almost certain this assumption was correct and the complete story until you and phusis informed me that a group of AVS forum members had figured out a method, using a mini-DSP, that allows the retrieval of any bass content still existing on numerous specific Bluray and DVD discs that's below 20 Hz.
     This was the first I was aware this was even possible on certain discs, so I wanted to thank both of you for bringing this to my attention.  As I stated, I'm very satisfied with my current system's bass performance on both music and HT even though it's currently restricted to only 20 Hz in bass extension.  
    However, I am curious about experiencing how I would perceive even further bass extension in my room and system.  I understand I would need to upgrade my current Audio Kinesis Debra 4-sub distributed bass array system, or at least the existing four 4 ohm passive subs with 10" aluminum long-throw drivers it uses, along with adding a mini-DSP unit to realize high quality deep bass below 20 Hz.  Even then, I understand this deeper bass would only accessible on certain HT Bluray and DVDs.  I think whether I decide to proceed depends on your answer to the following question:

     Does the mini-DSP also allow retrieval of deeper bass content on audio only discs such as CDs and SACDs?


Thanks,
 
 
 
   

@noble100 --

I think our disagreements and differences expressed on this thread can be boiled down to a difference in preferences and priorities. I could go into detail but I believe it basically comes down to both of your top priorities seeming to be the optimum bass extension of your sub systems for HT Bluray 4K Ultra HD audio performance and my top priority being the optimum bass quality of my sub system for 2-ch stereo music hi-res digital music file audio performance. I think both are enjoyable and worthy goals. But why can’t we have both?

Even though I fully acknowledge the impact <20Hz reproduction can have and that there’s plenty of source material to support it, not least watching movies via Blu-ray’s and UHD’s, as I’ve stated earlier I’ve chosen to consciously forego infrasonics in my own set-up. This is due to the nature imposed by design limits mostly, in addition to practical considerations in regards to sheer size; tapped horns, my preferred bass principle, are bandwidth limited to covering about 2 to 2 1/2 octaves cleanly (some would say 1 1/2 to 2 octaves, but it depends on the specific TH design and its weighted parameters within the given fold/expansion/compression ratio), and therefore a lower tune will at the same time "eat away" of the upper range that can be achieved. For those not in the need of a cross-over frequency above 50-60Hz here, 15Hz honest extension (or even lower in-room) can be had from tapped horns the likes of which count Josh Ricci’s monstrous Gjallarhorn V2, the Danley DTS-10 or lilmike’s LilWrecker. Apart from upper range limitations naturally imposed on these designs there’s also size to consider as they climb upwards of 30 cubic feet in volume, not to mention the added weight that follows. Moreover, a lower tune with tapped comes at the cost of sensitivity, though relative to direct radiating designs they are typically still more efficient even when tuned rather low. My MicroWrecker’s have a ~23Hz tune @97dB sensitivity that gives clean extension upwards to about or just below 100Hz, and with a 78Hz lowpass in my system to the mains (36dB/octave Linkwitz-Riley) no irregularities from the upper band of the MW’s interfere in the presentation. Highpassing the mains above some 70Hz has advantages in relieving them more effectively, but the exact cross-over frequency is one to be found with careful listening. A highpass at 20Hz (4th order Butterworth) protects the bass drivers of the MW’s downwards as they unload below the tune (in domestic use mostly to reduce theoretical distortion rather than over-excursion), and so 20Hz is pretty much the "hard deck." With the pair of MW’s this translates to +125dB’s SPL envelope and honest 20-25Hz reproduction. Some may regard such SPL capabilities in domestic environments as insane, but when faced with the effortless reproduction they deliver at any SPL one would care for, even having impact down to 60-70dB’s, it makes perfect sense.

So, my preference and priorities revolve around attaining the bass that best integrates with my mains as well as acquiring prodigious amounts of headroom, and this requires going the (tapped) horn route with massive physical size to follow, as well as bandwidth limitations to consider. Infrasonics make a difference, for sure, but I’d rather attain optimum integration and overall bass presentation, to my liking, and sacrifice <20Hz with the given tapped horn design. Choices, and compromises.. (sorry for lengthy elaboration above).