As some of my audiophile friends know my obsession with great bass continues. And the more I learn and listen it’s become increasingly apparent to me that in order to get true full - range effortless and accurate sound without compromise the ultimate in woofer to subwoofer integration would require converting / integrating my 4 – way Vivids to 5 - way with my subs rather than 4 ½ way (speaker woofers play as low as possible spec'd down to ~30Hz with subs overlapping ~45Hz) as almost everyone does. So the goal was:
Listening after two days of subwoofer tuning yields to my ears some of the best bass I've heard. The silence between the notes is palpable, the soundstage is wall to wall on more material, the dynamics are startling, and most unexpected part - the clarity is incredible. Reviewing the REW data I think the main reason for the sonic benefits is the reduction of disruptive low frequency energy in the room versus before. Specifically, the low frequency decay is reduced (and not by much btw) since with the 5 - way no bass drivers' frequency ranges overlap. As a test I played one of my favorite SACDs, The Bassface Trio Plays Gershwin, a direct cut SACD from Stockfisch studios which always exhibited quite loud and boomy bass especially with notes that showcased my room modes. With the 5 way setup, the bass was still quite loud - but crystal clear without any boominess. Other recordings with prominent bass yielded the same results.
Net is - Overlapping frequency duties even with optimal phase alignment are not as sonically beneficial as dedicated drivers per frequency ranges. Overlap can and does cause bass smearing and likely in many cases excessive decay. I urge anyone with a little DIY skill and subs integrated in he typical way to give this a try. With the mains out of the way for the bottom 2 octaves it should yield positive results for most IMO and IME. Happy Listening!
Steve
- Comply with Vivid Giya drivers’ specs covering about 2 octaves with the exception of the woofers (tweeter: 3.5K – ~16Khz, mid tweet – 880Hz – 3.5KHz, mid – 220Hz – 880Hz, woofers – 220Hz – 30Hz).
- The woofers you will notice cover almost 3 octaves and the bottom octave is the most difficult to deliver let alone with low distortion. It’s also the most work for an amplifier as the Vivids dip to 4-5 ohms from 120Hz and below so. They are an easy load above as they slope from 8 ohms and higher from 200Hz+. So if I can take the frequency load off the woofers and the woofer amp to only manage 200Hz -> 80Hz, I lower the distortion of the woofers, increase available power from the woofer amp and can have a true 5 way with the subs managing the bottom 2 octaves.
- Reduce the load on my preamp by moving the RCA sub outs from the preamp to high output -> low output converters. Currently my preamp has 2 pair of outputs which each amp occupies (1 for mids/highs, 1 for woofers). The subs are Y connected off the woofer amp RCAs - not a good solution. I've measured 1/4DB attenuation across the woofer frequency range with the 3rd subwoofer RCA outs connected = bad. This would alleviate the attenuation and hopefully result in a more balanced sound with possible better dynamics.
- Path to (hopefully) success
- Step 1: Removed the interconnects from the preamp out to the subwoofers by ordering / implementing custom Jensen high to low output subwoofer – specific converters. This takes the output from the amp, voltage divides it and attenuates it so the subwoofer can use it as an input (like Rel does). Specifically I had Jensen custom make the subwoofer – specific converters with Neutrik connectors inputs used in Pro Audio. This effectively reduced the output load on the preamp as it now only uses 2 pair of outputs to my amps. After integration the result was the best bass I’ve ever heard in my system. More dynamic, bigger soundstage and more effortless. I’ve rarely heard big, full bass this clean IMO. Maybe it was the scotch at the end
- Step 2: To make the Vivids -> JLAs a true 5 - way I needed to employ a high pass filter. The challenges is – anything more than a first order alters the phase but provides a greater attenuation. So I made a simple 80Hz first order high pass (only a cap in series leveraging the input impedance from my amp). After initial subwoofer tuning I’m achieved +/- 2.3DB aligned to the Sean Olive curve from 15Hz – 10KHz.
Listening after two days of subwoofer tuning yields to my ears some of the best bass I've heard. The silence between the notes is palpable, the soundstage is wall to wall on more material, the dynamics are startling, and most unexpected part - the clarity is incredible. Reviewing the REW data I think the main reason for the sonic benefits is the reduction of disruptive low frequency energy in the room versus before. Specifically, the low frequency decay is reduced (and not by much btw) since with the 5 - way no bass drivers' frequency ranges overlap. As a test I played one of my favorite SACDs, The Bassface Trio Plays Gershwin, a direct cut SACD from Stockfisch studios which always exhibited quite loud and boomy bass especially with notes that showcased my room modes. With the 5 way setup, the bass was still quite loud - but crystal clear without any boominess. Other recordings with prominent bass yielded the same results.
Net is - Overlapping frequency duties even with optimal phase alignment are not as sonically beneficial as dedicated drivers per frequency ranges. Overlap can and does cause bass smearing and likely in many cases excessive decay. I urge anyone with a little DIY skill and subs integrated in he typical way to give this a try. With the mains out of the way for the bottom 2 octaves it should yield positive results for most IMO and IME. Happy Listening!
Steve
