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    VTA-ST 120

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    Leigh W

    Posts : 45
    Join date : 2013-04-02

    VTA-ST 120

    Post by Leigh W on Tue Sep 03, 2013 8:00 pm

    I think I remember seeing something about the VTA ST-120 being bridgeable or not on this forum, but don't remember if it is or isn't. I've looked but can't seem to find the post. So the question is: Can Bob's VTA-ST 120 be used in bridge mode? If it can I will be purchasing another. If not, maybe a couple of 125's are in order. Thanks for any help......Leigh

    Bob Latino
    Admin

    Posts : 2374
    Join date : 2008-11-26
    Location : Massachusetts

    Re: VTA-ST 120

    Post by Bob Latino on Tue Sep 03, 2013 8:32 pm

    Hi Leigh,

     Yes - You can bridge the VTA ST-120 - BUT - It doesn't sound as good bridged as it does as a stereo amp do to the mixing of the two feedback lines of each channel. If you need 120 watts per stereo channel then you should BIAMP with two VTA ST-120 stereo amps. Most speakers have separate woofer and tweeter inputs. You just remove any straps between the woofer and tweeter sections and then run one ST-120 amp on each stereo channel. Send the left channel of one ST-120 to the woofer section of the speaker and the right channel to the tweeter section on the LEFT stereo channel. (or vice /versa) Next do the same thing on the RIGHT stereo channel with another VTA ST-120. You are now VERTICAL biaming which is the preferred way to biamp with these amps.

    Most preamps have TWO sets of outputs that help do this easier. If your preamp does NOT have two sets of inputs, you can just use a RCA Y connector with two male ends (plugged into each amp) and one female connector to receive the interconnect from your preamp.

    Bob

    Leigh W

    Posts : 45
    Join date : 2013-04-02

    Re: VTA-ST 120

    Post by Leigh W on Tue Sep 03, 2013 8:54 pm

    Thank you so much for the info Bob. Will running an amp on each channel split between the highs and lows defeat the crossover network of the speaker? I've heard you would need an outboard crossover network to do this. Maybe i have read wrong. I am running Klipsch RF'82's now that do have the ability to separate the woofers from the mids and tweeters. I am a Dynaco kit addict and would love to build another....Leigh

    Bob Latino
    Admin

    Posts : 2374
    Join date : 2008-11-26
    Location : Massachusetts

    Re: VTA-ST 120

    Post by Bob Latino on Tue Sep 03, 2013 9:26 pm

    No - You are still using the passive crossover inside the speaker. You don't NEED an active crossover but some people like them to alter the crossover point and/or adjust levels a bit.

    Below is a photo of my using two VTA ST-120's to drive two Magnepan MG 3.6R speakers with no active crossover - just directly into the woofer and tweeter sections of these speakers.

    Bob



    Leigh W

    Posts : 45
    Join date : 2013-04-02

    Re: VTA-ST 120

    Post by Leigh W on Tue Sep 03, 2013 9:31 pm

    Thank you Bob. Great info you have provided. Expect another order soon. Cheers....Leigh

    Sprags

    Posts : 123
    Join date : 2013-02-27

    Re: VTA-ST 120

    Post by Sprags on Wed Sep 04, 2013 12:59 am

    What is the make and model of the preamp you used in that setup Bob? Thanks...Blake

    Bob Latino
    Admin

    Posts : 2374
    Join date : 2008-11-26
    Location : Massachusetts

    Re: VTA-ST 120

    Post by Bob Latino on Wed Sep 04, 2013 8:37 am

    Sprags wrote:What is the make and model of the preamp you used in that setup Bob? Thanks...Blake
    Hi Blake,

     That preamp is a BAT (Balanced Audio Technology) VK30SE with a phono board.
     The turntable is a Music Hall MMF7 with a Goldring Eroica H moving coil cartridge

    Bob

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