Why no sub-out on 2ch. preamp?

begbie
begbie Posts: 630
edited July 2003 in 2 Channel Audio
I noticed this on some Rotel models and a few other brands that they don't have a sub-out. Shouldn't they ?
Polk Rt800i -Fronts
Polk cs400i -Center
Polk fx500i -side surrounds
Polk rc60i -rear surrounds
Onkyo TX-NR 1009 (9.2) receiver
Velodyne cht12
Polk psw111
Post edited by begbie on

Comments

  • begbie
    begbie Posts: 630
    edited July 2003
    Makes sense. Though I thought I read the pre-outs were for an external processor? Or am I getting myself all mixed up here ? :confused:
    Polk Rt800i -Fronts
    Polk cs400i -Center
    Polk fx500i -side surrounds
    Polk rc60i -rear surrounds
    Onkyo TX-NR 1009 (9.2) receiver
    Velodyne cht12
    Polk psw111
  • dcarlson
    dcarlson Posts: 1,740
    edited July 2003
    If it's just a 2ch preamp, it should only do 2 channel.

    It's not made to process a signal. It's your choice wether you want to run a sub or not.
    SDA-2a, Anthem Pre-2L, Anthem Amp 1, MF A324 DAC, Rotel RCD1070

    Senn HD650 Cardas, Mapletree Audio Ear+ HD2, Kimber KS1030, Bel Canto DAC2, M-Audio Transit, Laptop.
  • dragon1952
    dragon1952 Posts: 4,894
    edited July 2003
    You would have to run interconnects from the preamps pre-outs to the sub line-in and then interconnects from the sub line-out to the external amp in order to incorporate a sub into a 2 channel system. You could also connect the external amp to the preamp and then run speaker wires from the external amp to the sub speaker line-in and then from the sub speaker line-outs to the speakers.
    2 channel - Willsenton R8 tube integrated, Holo Audio Spring 3 KTE DAC, audio optimized NUC7i5, Windows 10 Pro/JRiver MC29/Fidelizer Plus 8.7 w/LPS and external SSD drive, PS Audio PerfectWave P3 regenerator, KEF R3 speakers, Rythmik F12SE subwoofer, Inakustik Reference USB cable, Gabriel Gold IC's, Morrow Audio SP5 speaker cables. Computer - Windows 10/JRiver, Schiit Magni 3+/Modi 3+, Fostex PMO.4n monitors, Sennheiser HD600 headphones
  • begbie
    begbie Posts: 630
    edited July 2003
    thanks, I think I'm getting it?! But if a manual says it can be used to pass the signal to another source than is it okay to send that signal to your sub ? :confused:

    Probably shouldn't sweat about it but just curious though.
    Polk Rt800i -Fronts
    Polk cs400i -Center
    Polk fx500i -side surrounds
    Polk rc60i -rear surrounds
    Onkyo TX-NR 1009 (9.2) receiver
    Velodyne cht12
    Polk psw111
  • organ
    organ Posts: 4,969
    edited July 2003
    Use a Y-adaptor. It has one male and two females. You'll be able to run two sets of interconnect from the single output. I suggest getting high quality Y-adaptor. Check monstercable.com, they have a very nice one.

    Maurice
  • dragon1952
    dragon1952 Posts: 4,894
    edited July 2003
    There are some pre-amps with sub outs....I've read about them in my internet travels here and there. In fact there was an H/K PT2300 that sold on ebay tonite for $105 that had them. Some newer ones do also, just can't think right now.
    2 channel - Willsenton R8 tube integrated, Holo Audio Spring 3 KTE DAC, audio optimized NUC7i5, Windows 10 Pro/JRiver MC29/Fidelizer Plus 8.7 w/LPS and external SSD drive, PS Audio PerfectWave P3 regenerator, KEF R3 speakers, Rythmik F12SE subwoofer, Inakustik Reference USB cable, Gabriel Gold IC's, Morrow Audio SP5 speaker cables. Computer - Windows 10/JRiver, Schiit Magni 3+/Modi 3+, Fostex PMO.4n monitors, Sennheiser HD600 headphones
  • dragon1952
    dragon1952 Posts: 4,894
    edited July 2003
    ATC......you are right on. You can certainly do that if you have two line outs.
    2 channel - Willsenton R8 tube integrated, Holo Audio Spring 3 KTE DAC, audio optimized NUC7i5, Windows 10 Pro/JRiver MC29/Fidelizer Plus 8.7 w/LPS and external SSD drive, PS Audio PerfectWave P3 regenerator, KEF R3 speakers, Rythmik F12SE subwoofer, Inakustik Reference USB cable, Gabriel Gold IC's, Morrow Audio SP5 speaker cables. Computer - Windows 10/JRiver, Schiit Magni 3+/Modi 3+, Fostex PMO.4n monitors, Sennheiser HD600 headphones
  • George Grand
    George Grand Posts: 12,258
    edited July 2003
    And unless you have an outboard cross-over unit, your going to be feeding a full-range signal to BOTH the sub-woofer AND your main speakers. Not a great idea.

    One of the reasons for employing a sub-woofer, is not to get super deep bass, but to relieve your main speakers the trouble of reproducing low frequencies that they probably can't reproduce anyway. There's all kind of benefits to that.

    You might have to use speaker level connections to your sub from your power amp, and then feed your main speakers a speaker level signal from the sub. There's no reason it wont work, and is an intelligent way to do it. Running the sub AND mains at full range is not.

    George Grand (of the Jersey Grand's)
  • Dr. Spec
    Dr. Spec Posts: 3,780
    edited July 2003
    Originally posted by George Grand
    You might have to use speaker level connections to your sub from your power amp, and then feed your main speakers a speaker level signal from the sub. There's no reason it wont work, and is an intelligent way to do it. Running the sub AND mains at full range is not.

    George Grand (of the Jersey Grand's)

    Agreed - it's the only way to do it when there is no sub out and you need to high pass the speaks.

    Unfortunately, it will require the amp to send a full power signal to the subwoofer. You won't reap the benefits of internal filtering before the amp stage like you would with digital BM in a pre/pro or AVR. Amps always run cooler, distort less, and have more dynamic range/headroom when relieved of the high-current bass duties.

    Doc
    "What we do in life echoes in eternity"

    Ed Mullen (emullen@svsound.com)
    Director - Technology and Customer Service
    SVS
  • tryrrthg
    tryrrthg Posts: 1,896
    edited July 2003
    Originally posted by George Grand
    And unless you have an outboard cross-over unit, your going to be feeding a full-range signal to BOTH the sub-woofer AND your main speakers. Not a great idea.

    One of the reasons for employing a sub-woofer, is not to get super deep bass, but to relieve your main speakers the trouble of reproducing low frequencies that they probably can't reproduce anyway. There's all kind of benefits to that.

    You might have to use speaker level connections to your sub from your power amp, and then feed your main speakers a speaker level signal from the sub. There's no reason it wont work, and is an intelligent way to do it. Running the sub AND mains at full range is not.

    George Grand (of the Jersey Grand's)
    not completely true... REL uses a full range signal to BOTH mains and sub. They claim that you will get a more seamless transition from mains to sub by allowing your mains to gradually roll-off and have the REL come up from underneath the mains. REL has the lowest crossovers that I know of. Allowing the crossovers in the low 20's.

    I think that without a sub crossover like REL running mains that can go into the upper 20's (or even 30's, since most sub crossovers stop at 35 or 40hz) full range will cause some problems. but running standmount speakers full range and bringing the sub up from under the standmounts can offer a terrific transition from speakers to sub.
    Sony KDL-40V2500 HDTV, Rotel RSX-1067 Receiver, Sony BDP-S550 Blu-ray, Slim Devices Squeezebox, Polk RTi6, CSi3 & R15, DIY sub with Atlas 15
  • tryrrthg
    tryrrthg Posts: 1,896
    edited July 2003
    EDIT: damn double post...
    Sony KDL-40V2500 HDTV, Rotel RSX-1067 Receiver, Sony BDP-S550 Blu-ray, Slim Devices Squeezebox, Polk RTi6, CSi3 & R15, DIY sub with Atlas 15
  • Dr. Spec
    Dr. Spec Posts: 3,780
    edited July 2003
    If you bridge the amp (if it has that capability), you will reduce it to a single channel output. Not sure what you are getting at here??

    Doc
    "What we do in life echoes in eternity"

    Ed Mullen (emullen@svsound.com)
    Director - Technology and Customer Service
    SVS
  • pjdami
    pjdami Posts: 1,894
    edited July 2003
    B&K PT5 two channel pre-amp can do it.

    It has a high pass output at 80 hz, low pass at 80 hz LFE for sub though it is fixed, mono output L + R for full range to the sub (use sub crossover) and a set of full range outputs for the mains as well.

    It's the main reason I went with a B&K preamp; that and B&K's excellent sound and reputation for making good mid-fi gear.

    Paul
  • RuSsMaN
    RuSsMaN Posts: 17,987
    edited July 2003
    Originally posted by Dr. Spec
    If you bridge the amp (if it has that capability), you will reduce it to a single channel output. Not sure what you are getting at here??

    Doc

    Doc, I think he is looking at using two AMC amps bridged. (100x2 or 250x1).

    Cheers,
    Rooster
    Check your lips at the door woman. Shake your hips like battleships. Yeah, all the white girls trip when I sing at Sunday service.
  • VR3
    VR3 Posts: 27,969
    edited July 2003
    Originally posted by tryrrthg
    REL has the lowest crossovers that I know of. Allowing the crossovers in the low 20's.

    @_@ My M&K does like 120-20hz. You can cross it over from 120hz all the way down to 20hz.
    - Not Tom ::::::: Any system can play Diana Krall. Only the best can play Limp Bizkit.
  • dragon1952
    dragon1952 Posts: 4,894
    edited July 2003
    You might have to use speaker level connections to your sub from your power amp, and then feed your main speakers a speaker level signal from the sub. There's no reason it wont work, and is an intelligent way to do it.

    I don't know if this is generaly true or not but I found this while searching for various methods of incorporating a sub in a 2-channel system:
    RE: connecting sub-
    "Using the "Speaker level" inputs requires some care, since this usually involves connecting it in "parallel" with other speakers, and therefore generally reduces the impedance of these connections putting more of a strain on your receivers amplifier."

    link=http://www.ramelectronics.net/html/howto-av.html
    2 channel - Willsenton R8 tube integrated, Holo Audio Spring 3 KTE DAC, audio optimized NUC7i5, Windows 10 Pro/JRiver MC29/Fidelizer Plus 8.7 w/LPS and external SSD drive, PS Audio PerfectWave P3 regenerator, KEF R3 speakers, Rythmik F12SE subwoofer, Inakustik Reference USB cable, Gabriel Gold IC's, Morrow Audio SP5 speaker cables. Computer - Windows 10/JRiver, Schiit Magni 3+/Modi 3+, Fostex PMO.4n monitors, Sennheiser HD600 headphones
  • RuSsMaN
    RuSsMaN Posts: 17,987
    edited July 2003
    Originally posted by Vr3MxStyler2k3
    :rolleyes: My M&K does like 120-20hz. You can cross it over from 120hz all the way down to 20hz.

    Cross it over at 20Hz? That's a hoot, considering that sub has almost ZERO useable output in entire first octave. ;)

    Cheers,
    Rooster
    Check your lips at the door woman. Shake your hips like battleships. Yeah, all the white girls trip when I sing at Sunday service.
  • VR3
    VR3 Posts: 27,969
    edited July 2003
    Originally posted by RuSsMaN
    Cross it over at 20Hz? That's a hoot, considering that sub has almost ZERO useable output in entire first octave. ;)

    Cheers,
    Rooster

    I never said it played that loud, I said you can cross it over there.....jeez, chill....;)
    - Not Tom ::::::: Any system can play Diana Krall. Only the best can play Limp Bizkit.
  • RuSsMaN
    RuSsMaN Posts: 17,987
    edited July 2003
    It's all good young buck, I have *three* powered, and *one* passive sub in use in my humble abode, and only *two* of those can hit 25Hz (room loaded) at a level thats remotely useable.

    Cheers,
    Rooster
    Check your lips at the door woman. Shake your hips like battleships. Yeah, all the white girls trip when I sing at Sunday service.
  • Dr. Spec
    Dr. Spec Posts: 3,780
    edited July 2003
    Cross it over at 20Hz? That's a hoot, considering that sub has almost ZERO useable output in entire first octave.

    Sid got owned.

    [URL=http://]violent-smiley-012.gif[/URL]
    "What we do in life echoes in eternity"

    Ed Mullen (emullen@svsound.com)
    Director - Technology and Customer Service
    SVS
  • tryrrthg
    tryrrthg Posts: 1,896
    edited July 2003
    Originally posted by Vr3MxStyler2k3
    :rolleyes: My M&K does like 120-20hz. You can cross it over from 120hz all the way down to 20hz.
    Why are you rolling your eyes?!? I said REL is the only sub I KNOW of that crosses over that low. I don't know anything about M&K... You could have just told me that without being a smart **** and acting like I'M the dumbass!
    Sony KDL-40V2500 HDTV, Rotel RSX-1067 Receiver, Sony BDP-S550 Blu-ray, Slim Devices Squeezebox, Polk RTi6, CSi3 & R15, DIY sub with Atlas 15
  • VR3
    VR3 Posts: 27,969
    edited July 2003
    Dont take that serious man, Cmon.....I just like that smiley - really - AIM should have it. MSN has a really cool one. Don't worry about it......gah! Everyone is so uptight around here!!!!!!!!:D

    Doc,
    Yep! I'm OWNED!

    Russ, I need a new Subwoofer.....lol
    - Not Tom ::::::: Any system can play Diana Krall. Only the best can play Limp Bizkit.
  • tryrrthg
    tryrrthg Posts: 1,896
    edited July 2003
    Originally posted by Vr3MxStyler2k3
    Dont take that serious man, Cmon.....I just like that smiley - really - AIM should have it. MSN has a really cool one. Don't worry about it......gah! Everyone is so uptight around here!!!!!!!!:D
    No biggie, it just came off the wrong way. water under the bridge my man.
    Originally posted by Vr3MxStyler2k3
    Russ, I need a new Subwoofer.....lol [/B]
    You and me both! :D But I need a new amp first!
    Sony KDL-40V2500 HDTV, Rotel RSX-1067 Receiver, Sony BDP-S550 Blu-ray, Slim Devices Squeezebox, Polk RTi6, CSi3 & R15, DIY sub with Atlas 15
  • VR3
    VR3 Posts: 27,969
    edited July 2003
    I plan to get the SVS 20-39 PCi. Just need the $$$$$!!
    - Not Tom ::::::: Any system can play Diana Krall. Only the best can play Limp Bizkit.
  • dragon1952
    dragon1952 Posts: 4,894
    edited July 2003
    My M&K does like 120-20hz. You can cross it over from 120hz all the way down to 20hz.

    Cross...over....at.....20....Hz :eek: Wha?! Huh!?
    What kinda sub would one own that they would set the x-over at 20Hz!?!?

    M&K must stand for "M"akin' it up' & just "K" iddin' !
    2 channel - Willsenton R8 tube integrated, Holo Audio Spring 3 KTE DAC, audio optimized NUC7i5, Windows 10 Pro/JRiver MC29/Fidelizer Plus 8.7 w/LPS and external SSD drive, PS Audio PerfectWave P3 regenerator, KEF R3 speakers, Rythmik F12SE subwoofer, Inakustik Reference USB cable, Gabriel Gold IC's, Morrow Audio SP5 speaker cables. Computer - Windows 10/JRiver, Schiit Magni 3+/Modi 3+, Fostex PMO.4n monitors, Sennheiser HD600 headphones