RTI A7 Bi Amp Impedance / Resistance

245

Comments

  • tonyb
    tonyb Posts: 32,902
    Show off... :p
    HT SYSTEM-
    Sony 850c 4k
    Pioneer elite vhx 21
    Sony 4k BRP
    SVS SB-2000
    Polk Sig. 20's
    Polk FX500 surrounds

    Cables-
    Acoustic zen Satori speaker cables
    Acoustic zen Matrix 2 IC's
    Wireworld eclipse 7 ic's
    Audio metallurgy ga-o digital cable

    Kitchen

    Sonos zp90
    Grant Fidelity tube dac
    B&k 1420
    lsi 9's
  • don0
    don0 Posts: 78
    nguyendot wrote: »
    The current is pulled from the same power supply in the receiver. Bi-wiring won't improve anything in the way you're describing, as the current is not only coming from the same power supply, but the same terminal jacks even - to the same amps.

    But it does not travel on the same wire and I can hear the difference.
  • F1nut
    F1nut Posts: 49,704
    The full frequencies are traveling on both sets of cables, which are traveling from the same place to the same crossover, which splits the signal the same way it does with jumpers in place. The only difference when bi-wiring is you are effectively increasing the wire gauge, which could be done with a single run as well.
    Political Correctness'.........defined

    "A doctrine fostered by a delusional, illogical minority and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a t-u-r-d by the clean end."


    President of Club Polk

  • nguyendot
    nguyendot Posts: 3,594
    don0 wrote: »
    nguyendot wrote: »
    The current is pulled from the same power supply in the receiver. Bi-wiring won't improve anything in the way you're describing, as the current is not only coming from the same power supply, but the same terminal jacks even - to the same amps.

    But it does not travel on the same wire and I can hear the difference.

    Same frequencies, fed to same crossover with portions of the sound tossed out via heat. You aren't gaining anything, and if put to a test will reveal no differences. Put a scope on it and see.
    Main Surround -
    Epson 8350 Projector/ Elite Screens 120" / Pioneer Elite SC-35 / Sunfire Signature / Focal Chorus 716s / Focal Chorus CC / Polk MC80 / Polk PSW150 sub

    Bedroom - Sharp Aquos 70" 650 / Pioneer SC-1222k / Polk RT-55 / Polk CS-250

    Den - Rotel RSP-1068 / Threshold CAS-2 / Boston VR-M60 / BDP-05FD
  • don0
    don0 Posts: 78
    nguyendot wrote: »
    don0 wrote: »
    nguyendot wrote: »
    The current is pulled from the same power supply in the receiver. Bi-wiring won't improve anything in the way you're describing, as the current is not only coming from the same power supply, but the same terminal jacks even - to the same amps.

    But it does not travel on the same wire and I can hear the difference.

    Same frequencies, fed to same crossover with portions of the sound tossed out via heat. You aren't gaining anything, and if put to a test will reveal no differences. Put a scope on it and see.

    My ears are the test, the same as yours are when you think that fancy insulation and fancy covers on your high priced cables make them sound better than another cable with the same ga wire.
  • F1nut
    F1nut Posts: 49,704
    Fail
    Political Correctness'.........defined

    "A doctrine fostered by a delusional, illogical minority and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a t-u-r-d by the clean end."


    President of Club Polk

  • don0
    don0 Posts: 78
    F1nut wrote: »
    Fail

    Not Fail. You did not hear my system.
  • F1nut
    F1nut Posts: 49,704
    edited May 2016
    I'm referring to your uninformed comments concerning cables.

    It is funny you bring up gauge though as that is the only reason you might hear a difference from bi- wiring. However, as I stated previously you could get the same results from a single run.
    Post edited by F1nut on
    Political Correctness'.........defined

    "A doctrine fostered by a delusional, illogical minority and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a t-u-r-d by the clean end."


    President of Club Polk

  • don0
    don0 Posts: 78
    edited May 2016
    F1nut wrote: »
    I'm referring to your uninformed comments concerning cables.

    It is funny you bring up gauge though as that is the only reason you might hear a difference from bi- wiring. However, as I stated previously you could get the same results from a single run.
    F1nut wrote: »
    I'm referring to your uninformed comments concerning cables.

    It is funny you bring up gauge though as that is the only reason you might hear a difference from bi- wiring. However, as I stated previously you could get the same results from a single run.

    I did not say that gauge was the reason I can hear a difference. I said it is because the woofer and midrange current does not travel on the same wire as the tweeter, so that it does not interfere with the tweeter.

    Someone above implied (He said frequency) that the current is the same on all wires that are connected to the same terminal. Not true
    Try plugging a lamp with 100W bulb and a 1500W heater heater into the same wall outlet and measure the current with an amp meter. One will read about 1 amp=100W and the other will read about 15 amps=1500W. They share the same source.

    I said that the same gauge wire will probally sound the same as another wire with the same gauge, assuming that they are borh good copper. The expensive cover probably does not change the sound.

    I know that mine sounds better with 12ga wire than it does with 14ga wire.

  • F1nut
    F1nut Posts: 49,704
    Both sets of wires carry the exact same full range signal. Repeat that sentence until it sinks in.
    Political Correctness'.........defined

    "A doctrine fostered by a delusional, illogical minority and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a t-u-r-d by the clean end."


    President of Club Polk

  • F1nut
    F1nut Posts: 49,704
    edited May 2016
    don0 wrote: »

    I said that the same gauge wire will probally sound the same as another wire with the same gauge, assuming that they are borh good copper. The expensive cover probably does not change the sound.

    I know that mine sounds better with 12ga wire than it does with 14ga wire.

    Getting back to this. There's more to cable than just the gauge. Your assumption above discounts a multitude of things such as solid, stranded or a combination, the actual configuration, the dielectric and the purity of the metal. The commonly used Techflex cover material is actually rather inexpensive.

    Post edited by F1nut on
    Political Correctness'.........defined

    "A doctrine fostered by a delusional, illogical minority and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a t-u-r-d by the clean end."


    President of Club Polk

  • tonyb
    tonyb Posts: 32,902
    Dono,

    The guys are factually correct, but we are not denying you don't hear a difference. I think the reason for your slight difference is that with bi-wiring you have replaced those crappy brass jumper plates between the top and bottom posts of the speaker with some good speaker wire instead.

    You could also accomplish the same thing by making your own jumpers, buying them, instead of buying a whole run of bi-wired cables.

    Comes down to a matter of preference is all, either way.....those brass jumpers get replaced with better quality and that's probably the source of the better audio your hearing.
    HT SYSTEM-
    Sony 850c 4k
    Pioneer elite vhx 21
    Sony 4k BRP
    SVS SB-2000
    Polk Sig. 20's
    Polk FX500 surrounds

    Cables-
    Acoustic zen Satori speaker cables
    Acoustic zen Matrix 2 IC's
    Wireworld eclipse 7 ic's
    Audio metallurgy ga-o digital cable

    Kitchen

    Sonos zp90
    Grant Fidelity tube dac
    B&k 1420
    lsi 9's
  • don0
    don0 Posts: 78
    edited May 2016
    F1nut wrote: »
    Both sets of wires carry the exact same full range signal. Repeat that sentence until it sinks in.

    Not same current. You research that. The lamp and heater example carry the same 60Hz but not the same current. It is the same with the woofer and tweeter.

    The tweentr is not in the same circuit as the midrange and woofer. If the jumpers are in place, some of the woofer current can interect with the tweeter because the crossover does not have a definite cutoff point. If it did there would be apaces between the woofer and tweeter where the sound would be missing.
  • don0
    don0 Posts: 78
    nbrowser wrote: »
    don0 wrote: »

    I did not say that gauge was the reason I can hear a difference. I said it is because the woofer and midrange current does not travel on the same wire as the tweeter, so that it does not interfere with the tweeter.

    Incorrect, the midrange and tweeter are fed from the upper binding posts, the dual 7 inch woofers are fed by the lower binding posts. I've also done to bi-wiring thing with my RTiA7 towers with benefits but that was with a fairly powerful 2 channel receiver. And yes, F1Nut is right both sets of wires carry the full signal.

    Wrong. My tweeter is fed form the top post and the two midrange and two woofers are fed from the bottom post.
  • don0
    don0 Posts: 78
    nguyendot wrote: »
    don0 wrote: »
    nguyendot wrote: »
    The current is pulled from the same power supply in the receiver. Bi-wiring won't improve anything in the way you're describing, as the current is not only coming from the same power supply, but the same terminal jacks even - to the same amps.

    But it does not travel on the same wire and I can hear the difference.

    Same frequencies, fed to same crossover with portions of the sound tossed out via heat. You aren't gaining anything, and if put to a test will reveal no differences. Put a scope on it and see.

    A scope will not show what the tweeter sounds like.
  • don0
    don0 Posts: 78
    tonyb wrote: »
    Dono,

    The guys are factually correct, but we are not denying you don't hear a difference. I think the reason for your slight difference is that with bi-wiring you have replaced those crappy brass jumper plates between the top and bottom posts of the speaker with some good speaker wire instead.

    You could also accomplish the same thing by making your own jumpers, buying them, instead of buying a whole run of bi-wired cables.

    Comes down to a matter of preference is all, either way.....those brass jumpers get replaced with better quality and that's probably the source of the better audio your hearing.

    The above is not true. I had replaced the jumpers with wire before I tried bi-wiring or bi-amping. The latter two sound better.
  • F1nut
    F1nut Posts: 49,704
    What we've got here is a failure to communicate. Some men you can't reach.
    Political Correctness'.........defined

    "A doctrine fostered by a delusional, illogical minority and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a t-u-r-d by the clean end."


    President of Club Polk

  • don0
    don0 Posts: 78
    don0 wrote: »
    F1nut wrote: »
    Both sets of wires carry the exact same full range signal. Repeat that sentence until it sinks in.

    Not same current. You research that. The lamp and heater example carry the same 60Hz but not the same current. It is the same with the woofer and tweeter.

    The tweentr is not in the same circuit as the midrange and woofer. If the jumpers are in place, some of the woofer current can interect with the tweeter because the crossover does not have a definite cutoff point. If it did there would be spaces between the woofer and tweeter where the sound would be missing.

  • F1nut
    F1nut Posts: 49,704
    Maybe if you read it from another source.
    Bi-wiring

    Bi-wiring requires speakers with two pairs of binding posts for speaker wire. Many upscale loudspeakers now come with this configuration, including a removable shorting bar that connects the two "+" and the two "-" terminals for use with normal, single pair, speaker wire. One set of binding posts connects to the high frequency side of the passive crossover inside the speaker box and the other set of binding posts connects to the low frequency side of the crossover. The shorting bar (when left in place) insures that both sides of the crossover receive the same input signal.

    Remove the shorting bar and the speaker is ready for bi-wiring. This procedure runs two lengths of two-conductor speaker wire in parallel from the power amplifier's output to the dual binding posts on the loudspeaker. Note that these dual speaker wires are shorted together at the amplifier end; thus, both speaker cables are carrying the same signal from the amplifier to the loudspeaker. One speaker wire is attached to the high frequency side of the speaker's crossover binding posts and the other is attached to the low frequency side. It doesn't matter which wire pair goes to which side of the crossover, since both are identical. The result is both sides of the crossover getting the same, identical signal, just as it would if the shorting bar were in place and both sides of the crossover were fed by one speaker cable.
    Political Correctness'.........defined

    "A doctrine fostered by a delusional, illogical minority and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a t-u-r-d by the clean end."


    President of Club Polk

  • don0
    don0 Posts: 78
    F1nut wrote: »
    Maybe if you read it from another source.
    Bi-wiring

    Bi-wiring requires speakers with two pairs of binding posts for speaker wire. Many upscale loudspeakers now come with this configuration, including a removable shorting bar that connects the two "+" and the two "-" terminals for use with normal, single pair, speaker wire. One set of binding posts connects to the high frequency side of the passive crossover inside the speaker box and the other set of binding posts connects to the low frequency side of the crossover. The shorting bar (when left in place) insures that both sides of the crossover receive the same input signal.

    Remove the shorting bar and the speaker is ready for bi-wiring. This procedure runs two lengths of two-conductor speaker wire in parallel from the power amplifier's output to the dual binding posts on the loudspeaker. Note that these dual speaker wires are shorted together at the amplifier end; thus, both speaker cables are carrying the same signal from the amplifier to the loudspeaker. One speaker wire is attached to the high frequency side of the speaker's crossover binding posts and the other is attached to the low frequency side. It doesn't matter which wire pair goes to which side of the crossover, since both are identical. The result is both sides of the crossover getting the same, identical signal, just as it would if the shorting bar were in place and both sides of the crossover were fed by one speaker cable.

    I am not talking about signal. I am talking about current. Lamp and heater example.

    Tweeter and woffer current are not the same, signals are the same.
  • don0
    don0 Posts: 78
    edited May 2016
    F1nut wrote: »
    What we've got here is a failure to communicate. Some men you can't reach.

    I understand every word that you wrote. I also understand that you do not know everything about everyone else's systems or everything about electronics and electricity.

    Either bi-amping or bi-wiring my speakers seems to make the tweeters sound a little better on some female voices, especially on classical or opera music.

    This is my original post story and I am sticking to it.
  • F1nut
    F1nut Posts: 49,704
    Everyone is telling you the same thing that I have, even an outside source. If you refuse to believe the facts, that's pretty silly. Good luck to you, I'm done here.
    Political Correctness'.........defined

    "A doctrine fostered by a delusional, illogical minority and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a t-u-r-d by the clean end."


    President of Club Polk

  • nguyendot
    nguyendot Posts: 3,594
    don0 wrote: »
    nguyendot wrote: »
    don0 wrote: »
    nguyendot wrote: »
    The current is pulled from the same power supply in the receiver. Bi-wiring won't improve anything in the way you're describing, as the current is not only coming from the same power supply, but the same terminal jacks even - to the same amps.

    But it does not travel on the same wire and I can hear the difference.

    Same frequencies, fed to same crossover with portions of the sound tossed out via heat. You aren't gaining anything, and if put to a test will reveal no differences. Put a scope on it and see.

    My ears are the test, the same as yours are when you think that fancy insulation and fancy covers on your high priced cables make them sound better than another cable with the same ga wire.

    What the f are you smoking? What cables of mine? You don't have a clue what cables I run to even make that assumption.
    Main Surround -
    Epson 8350 Projector/ Elite Screens 120" / Pioneer Elite SC-35 / Sunfire Signature / Focal Chorus 716s / Focal Chorus CC / Polk MC80 / Polk PSW150 sub

    Bedroom - Sharp Aquos 70" 650 / Pioneer SC-1222k / Polk RT-55 / Polk CS-250

    Den - Rotel RSP-1068 / Threshold CAS-2 / Boston VR-M60 / BDP-05FD
  • don0
    don0 Posts: 78
    F1nut wrote: »
    Everyone is telling you the same thing that I have, even an outside source. If you refuse to believe the facts, that's pretty silly. Good luck to you, I'm done here.

    Good, because I know what I hear and I didn't ask you to tell me that I don't.
  • don0
    don0 Posts: 78
    edited May 2016
    nguyendot wrote: »
    don0 wrote: »
    nguyendot wrote: »
    The current is pulled from the same power supply in the receiver. Bi-wiring won't improve anything in the way you're describing, as the current is not only coming from the same power supply, but the same terminal jacks even - to the same amps.

    But it does not travel on the same wire and I can hear the difference.

    Same frequencies, fed to same crossover with portions of the sound tossed out via heat. You aren't gaining anything, and if put to a test will reveal no differences. Put a scope on it and see.

    This is the thread that I was referring. You said that (You aren't gaining anything and a test would reveal that.) The cable comment was to show (not necessarily referring to you or any one person) that the ears are the test.
    You are wrong. I can hear a difference on some female voices on opera and classical songs. I stated a fact and was told that I am lying.
    I am smoking the lying card.
  • tonyb
    tonyb Posts: 32,902
    I don't think anyone said you were lying about hearing a difference, just the reasons why you said you heard a difference.

    Are you bi-amping or bi-wiring ? Using a receiver to bi-amp ? If your using bi-wired cables, are they the same gauge for both top and bottom ? Did you change brands of cable over your single runs ?
    HT SYSTEM-
    Sony 850c 4k
    Pioneer elite vhx 21
    Sony 4k BRP
    SVS SB-2000
    Polk Sig. 20's
    Polk FX500 surrounds

    Cables-
    Acoustic zen Satori speaker cables
    Acoustic zen Matrix 2 IC's
    Wireworld eclipse 7 ic's
    Audio metallurgy ga-o digital cable

    Kitchen

    Sonos zp90
    Grant Fidelity tube dac
    B&k 1420
    lsi 9's
  • gp4jesus
    gp4jesus Posts: 1,969
    While reading this thread, saddened it became another "mudslinger," it occurred to me two possible/probable benefits (read that SQ improvement!) to passive bi-amping the RTi A7 by AVR:
    1. The channel connected to the MIT/tweet has just their back EMF w/which to cope. Same for the other channel connected to the bass drivers.
    2. Each channel "sees" 8 ohms. Enough of us know all too well, low to mid priced AVRs are, at best, so-so to, at worst, just flat lousy driving lower impedance loads. Any contrary opinions can't change this fact: the 'A7's impedance drops to 4 ohms below 125hz. That said even in a 5.1 system, w/'A7 LRs bi-amped by an AVR rated at, say 90 X 2, 75 X 4, and of course less X 5, SHOULD sound better and "see" more power w/less distortion. WHY NOT?!

    A side note to the above is internal wiring upgrades - worth it? I've never regretted it. 2-3 years ago I recall a thread w/a couple of naysayers that never tried it. To them and similar type naysayers of these other topics such as the above I say leave my house! Claiming something doesn't work one has never tried is saying you don't like this or that food or when you've never tried it, how silly!

    Tony
    Samsung 60" UN60ES6100 LED Outlaw Audio 976 Pre/Pro Samsung BDP, Amazon Firestick, Phillips CD Changer Canare 14 ga - LCR tweeters inside*; Ctr Ch outside BJC 10 ga - LCR mids, inside* & out 8 ga Powerline: LR woofers, inside* & out *soldered LR: Tri-amped RTi A7 w/Rotels. Woofers - 980BX; Tweets & “Plugged*” Mids - 981, connected w/MP Premiere ICs Ctr Ch: Rotel RB981 -> Bi-amped CSi A6 Surrounds: Premiere ICs ->Rotel 981 -> AR 12 ga -> RTi A3. 5 Subs: Sunfire True SW Signature -> LFE & Ctr Ch; 4 Audio Pro Evidence @ the “Corners”. Power Conditioning & Distribution: 4 dedicated 20A feeds; APC H15; 5 Furman Miniport 20s *Xschop's handy work
  • F1nut
    F1nut Posts: 49,704
    That said even in a 5.1 system, w/'A7 LRs bi-amped by an AVR rated at, say 90 X 2, 75 X 4, and of course less X 5, SHOULD sound better and "see" more power w/less distortion. WHY NOT?!

    If you study your own words you should realize, WHY NOT.



    Political Correctness'.........defined

    "A doctrine fostered by a delusional, illogical minority and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a t-u-r-d by the clean end."


    President of Club Polk

  • tonyb
    tonyb Posts: 32,902
    don0 wrote: »
    Either bi-amping or bi-wiring my speakers seems to make the tweeters sound a little better on some female voices, especially on classical or opera music.
    I believe it is because the high current of the woofers do not reach the tweeters.

    I believe this statement is what sent the thread downhill.

    Your speakers have a built in crossover that act like a traffic cop, x frequencies go here, Y frequencies go there. You can adjust which frequencies are sent to the speakers by way of bass management, but the speaker itself still uses it's own internal crossover. This is why when talking current, proper bi-amping requires separate amps and a separate crossover. When bi-amping with a receiver, your robbing Peter to pay Paul, but in 2 channel only, I can see a slight change in sound happening. Passive bi-amping is simply throwing more current to both top and bottom portions of the speaker while still using the speakers internal crossover. Many do this with external amps, and the reason most don't with receivers is that when talking current, most receivers are pretty lackluster in that department. So asking it to put out more current is like trying to squeeze blood from a Turnip. If you dig into the specs of most receivers, they all use the same 450-600 watt transformer to power all 5-7 channels. There is no independent channels of power like monoblock amps. Every bit of power asked of it is pooled from the same source.

    That said, I would be amazed if the tweeters on the RTIA 7's used more than 25 watts total. It's not soaking up a lot of current to begin with. Less current may have an effect on the sound but I would think a negative one. Bi-wiring isn't changing the current going to either the woofer or tweeter.....providing they are the same gauge.

    Maybe more details Don, and we can figure out why you hear what you hear. We aren't denying you don't hear things, just the reasons you stated why . Bi-amping and bi-wiring are 2 separate things.

    HT SYSTEM-
    Sony 850c 4k
    Pioneer elite vhx 21
    Sony 4k BRP
    SVS SB-2000
    Polk Sig. 20's
    Polk FX500 surrounds

    Cables-
    Acoustic zen Satori speaker cables
    Acoustic zen Matrix 2 IC's
    Wireworld eclipse 7 ic's
    Audio metallurgy ga-o digital cable

    Kitchen

    Sonos zp90
    Grant Fidelity tube dac
    B&k 1420
    lsi 9's
  • don0
    don0 Posts: 78
    tonyb wrote: »
    I don't think anyone said you were lying about hearing a difference, just the reasons why you said you heard a difference.

    Are you bi-amping or bi-wiring ? Using a receiver to bi-amp ? If your using bi-wired cables, are they the same gauge for both top and bottom ? Did you change brands of cable over your single runs ?

    Same ga and brand everywhere including the jumpers.

    Several posters above say that I said that I heard can not be true.

    I was only telling the original poster what I heard and several people jumped in and said NOT TRUE.