CECAA850 Posted March 6, 2014 Share Posted March 6, 2014 Ok, fixed crossover at 90Hz. Run parallel as they've suggested and as I've done on my back patio. You can parallel off of your main amp by running 2 sets of wires off each terminal. You can also parallel at your sub amp by running your speakers off the input posts. Depending where your speakers are in relation to your sub, you can splice drops off your wires running from the amp to your sub (which is how I had to do it). Quote Link to comment Share on other sites More sharing options...
CECAA850 Posted March 6, 2014 Share Posted March 6, 2014 I'd start by adjusting the crossover on your SVS to 50-55Hz and go from there. Quote Link to comment Share on other sites More sharing options...
USNRET Posted March 6, 2014 Author Share Posted March 6, 2014 I'll close this out for now with one last bit of info that I received from SVS. To SVS: Thanks again, any problem having speaker level input (from my 2 channel tube amps) and line level inputs (from my HT pre-pro) physically connected at the same time as long as one source is OFF. Response: Hi Michael, No problem hooking up both line and speaker-level at the same time. Even if both sources are active, you'll simply hear both. The Plus/2 is a classic! Don’t see too many folks letting go of them. Quote Link to comment Share on other sites More sharing options...
erik2A3 Posted March 6, 2014 Share Posted March 6, 2014 The response you received is what I outlined above. Run the sub amp off the main speakers, in other words, in parallel with the amplifier. You are NOT using the other set of speaker outputs on the subwoofer. This is the whole point of my post on using the speaker level inputs, only. Use the crossover control and variable phase adjustment on the subwoofer to find the response you prefer. Its very straightforward, and sounds extremely good in my view. I run my own sub off the main amplifier output transformers as well. I've correspond with a number of people who didn't realize it was possible to run the sub in this fashion. If you're not sure what to do, send an email or post here. Quote Link to comment Share on other sites More sharing options...
erik2A3 Posted March 6, 2014 Share Posted March 6, 2014 The fixed 90Hz crossover point has to do with the speaker outputs on the subwoofer. You're not using that. You bypass the speaker outputs altogether, and choose the crossover frequency for the sub on the variable crossover control on the plate amp. If you connect your main speakers to the sub speaker outputs, the signal they get is filtered by the fixed internal crossover between the speaker inputs and speaker outputs -- not the ideal choice, as SVS indicated. You connect BOTH the subwoofer speaker inputs AND your main speakers in parallel with the VRDs. If the VRDs accept both spades (or bare wire) and banana jacks, use the combination, or two spades under each binding post for the connections. Quote Link to comment Share on other sites More sharing options...
USNRET Posted March 6, 2014 Author Share Posted March 6, 2014 Thanks, I'm good now. What I did not realize was that the sub plate amp speaker level input accepted amplified signal and "re-amplified". I always considered the high level inputs to take amplified speaker level power and send directly to the drivers (well perhaps not directly maybe low cut / high cut / crossed). I have some things to try. Quote Link to comment Share on other sites More sharing options...
erik2A3 Posted March 7, 2014 Share Posted March 7, 2014 Understood and good. Quote Link to comment Share on other sites More sharing options...
jcmusic Posted March 7, 2014 Share Posted March 7, 2014 Erik, This is interesting, so you are saying that by using the speaker level imputs instead of the line level imputs you get a better sounding sub or what? Quote Link to comment Share on other sites More sharing options...
Ski Bum Posted March 7, 2014 Share Posted March 7, 2014 Erik, This is interesting, so you are saying that by using the speaker level imputs instead of the line level imputs you get a better sounding sub or what? I think that this relevant particularly if you're using a tube amp with a distinctive sonic personality; you preserve whatever that personality is across the board (subs and mains) by using the speaker level inputs. Quote Link to comment Share on other sites More sharing options...
CECAA850 Posted March 7, 2014 Share Posted March 7, 2014 That's why I love this place, I'm always learning. I would have thought there would be no sonic difference between using the sub's high level or low level inputs. I'll have to experiment. Quote Link to comment Share on other sites More sharing options...
erik2A3 Posted March 7, 2014 Share Posted March 7, 2014 It's what I generally prefer. In my experience, the sonic qualities of tube amplifiers reside more in the mid-range to higher frequencies, not so much lower frequencies. Subsequently, and also in my opinion, the main amplifier, which is in common with both the sub amp and the main L/R speaker, can be either transistor or vacuum-tube based. However, not all valve amps make automatically suitable candidates. Very low powered single ended triode amps, may (subjectively, of course), be less well adapted, particulalrly in cases where the filaments, which in some tubes also form the cathode, are heated with an AC filament supply. The reason is that the output stage of such an amp often carries includes a noise artifact in the form of low-level 60 cycle AC line noise, and that will continue on to the subwoofer and possibly amplified further. The VRDs should be good candidates, however, which is why I brought up the speaker level connection in the first place. Due to the difference in overal design, the VRD is inherently quieter in that it will self-cancel much of the noise elements assosciated with (some) directly AC heated filament/cathode tubes. A transistor amp will be quieter still, and in fact may have other advantages. Some tube amp designers I know of, include line-level outputs on their products that are derived from them output stage of their amps (meaning that they are taken off the output transformers) and sent through a voltage divider to drop the signal to a strong line level. The connection between that output and another component, which could be another amp (such as might be used for passive bi-amping) or the plate amp of a subwoofer, is then made via an RCA jacl for each channel. In other words, a line level signal that's connected to the subwoofers line-level inputs. I smile because this is yet another example of how vintage audio design still has great validity today. Everything I just mentioned above has already been done, and in one case, by a very illustrious and intelligent gentleman who is the reason behind this very forum. Paul Klipsch did exactly the same thing with his "Mini Box". It's the device he used to create a third, center-fill channel that improved the strength of central imaging between a pair of Klipschorns installed in a wide space. And in fact it was experimenting with this very application that led me to try the same thing with a subwoofer. We talked about the Mini Box in the old days on this forum - things around here now are a bit different, for the most part, than they were in 2002. Some members will remember.... Quote Link to comment Share on other sites More sharing options...
USNRET Posted March 7, 2014 Author Share Posted March 7, 2014 SUCCESS!!!!!!!! Quote Link to comment Share on other sites More sharing options...
CECAA850 Posted March 7, 2014 Share Posted March 7, 2014 SUCCESS!!!!!!!! How'd you get Friday off??????? Quote Link to comment Share on other sites More sharing options...
USNRET Posted March 7, 2014 Author Share Posted March 7, 2014 (edited) SUCCESS!!!!!!!! How'd you get Friday off??????? Had to wait on the "Cable Guy" from U-verse to show and and tell me that he could not connect me. Now waiting on 12:00 to get here so I can pop a top! Edited March 7, 2014 by USNRET Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.