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    Using all speaker taps -- new build.

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    StevieRay

    Posts : 27
    Join date : 2009-01-09
    Age : 56
    Location : Central VA

    Using all speaker taps -- new build.

    Post by StevieRay on Wed Oct 31, 2018 2:24 pm

    Well after lurking here for many years, just yesterday I received my brand spanking new VTA ST-120 kit.

    'Just gathering things up, thinking things through at this point.....

    The newest kits come with binding posts for ground (black) and two other taps.

    I'll be experimenting with the two sets of speakers I have on different taps (using 4 ohm tap I know for MMG's),but friends occasionally bring over different small bookshelf speakers to experiment with.

    I would like to be able to use all 3 (4/8/16 ohm) taps without having to rewire at times.

    Without having to resort to the original Dynaco type terminal lugs, 'any of you got suggestions on how /where to mount another binding post, or be able to select between 2 to use with the 2-tap posts now shipping?
    I heard that the stainless steel chassis is hard to drill (not that I want to do that anyway).

    If some of the original types were plated with something besides tin, I might consider those also.

    Suggestions, pics on how to have all 3 taps available?
    avatar
    peterh

    Posts : 1054
    Join date : 2012-12-25
    Location : gothenburg, sweden

    Re: Using all speaker taps -- new build.

    Post by peterh on Wed Oct 31, 2018 3:00 pm

    StevieRay wrote:Well after lurking here for many years, just yesterday I received my brand spanking new VTA ST-120 kit.

    'Just gathering things up, thinking things through at this point.....

    The newest kits come with binding posts for ground (black) and two other taps.

    I'll be experimenting with the two sets of speakers I have on different taps (using 4 ohm tap I know for MMG's),but friends occasionally bring over different small bookshelf speakers to experiment with.

    I would like to be able to use all 3 (4/8/16 ohm) taps without having to rewire at times.

    Without having to resort to the original Dynaco type terminal lugs, 'any of you got suggestions on how /where to mount another binding post, or be able to select between 2 to use with the 2-tap posts now shipping?
    I heard that the stainless steel chassis is hard to drill (not that I want to do that anyway).

    If some of the original types were plated with something besides tin, I might consider those also.

    Suggestions, pics on how to have all 3 taps available?
    I found terminal barrier strip on ebay :
    See last photo on : http://n.manet.nu/vta70/index.html
    avatar
    Peter W.

    Posts : 965
    Join date : 2016-08-07
    Location : Melrose Park, PA

    Re: Using all speaker taps -- new build.

    Post by Peter W. on Wed Oct 31, 2018 3:23 pm

    StevieRay wrote:Well after lurking here for many years, just yesterday I received my brand spanking new VTA ST-120 kit.

    'Just gathering things up, thinking things through at this point.....

    The newest kits come with binding posts for ground (black) and two other taps.

    I'll be experimenting with the two sets of speakers I have on different taps (using 4 ohm tap I know for MMG's),but friends occasionally bring over different small bookshelf speakers to experiment with.

    I would like to be able to use all 3 (4/8/16 ohm) taps without having to rewire at times.

    Without having to resort to the original Dynaco type terminal lugs, 'any of you got suggestions on how /where to mount another binding post, or be able to select between 2 to use with the 2-tap posts now shipping?
    I heard that the stainless steel chassis is hard to drill (not that I want to do that anyway).

    If some of the original types were plated with something besides tin, I might consider those also.

    Suggestions, pics on how to have all 3 taps available?

    I am not precisely sure of what you want. But, if you wish to be able to access any tap at any time, I suggest you get a three-position, double-pole rotary switch and use that as an outboard addition. Point being that at no time do you want to be loading more than one tap, and at no time do you want to let the amp be unloaded when receiving signal. A rotary switch handles that nicely.

    https://www.mouser.com/ProductDetail/Grayhill/44MS45-01-2-03N?qs=sGAEpiMZZMvNbjZ2WlReYhndqMY8foDI7lBNzHrn6r0%3d

    Get something that has the capacity to switch 150 watts at about 40 volts AC. Remember, there should be NO DC on the speaker outputs. At all.

    StevieRay

    Posts : 27
    Join date : 2009-01-09
    Age : 56
    Location : Central VA

    Re: Using all speaker taps -- new build.

    Post by StevieRay on Wed Oct 31, 2018 3:55 pm

    I'm just looking for some way to have all 3 taps. The selector switch is out of the question. I hate to put another binding post in and have to drill a hole, but I may do that.

    When using my primary speakers (Quad ESL-57's), different transformer taps can act like a tone control because of the wildly varying impedance. I'm just looking for a quick, easy way to try and use all those taps.

    The original design did have all available, but then those leave much to be desired also.

    StevieRay

    Posts : 27
    Join date : 2009-01-09
    Age : 56
    Location : Central VA

    Re: Using all speaker taps -- new build.

    Post by StevieRay on Wed Oct 31, 2018 4:05 pm

    Alas! -- I found these, but out of stock Crying or Very sad

    I use bananas exclusively now, so this is an option.

    I could make my own with Pamona bananas if I know where to get that phenolic board.......

    https://www.dynakitparts.com/shop/4-terminal-banana-jacks/
    avatar
    peterh

    Posts : 1054
    Join date : 2012-12-25
    Location : gothenburg, sweden

    Re: Using all speaker taps -- new build.

    Post by peterh on Thu Nov 01, 2018 6:35 pm

    avatar
    DynakitParts
    Admin

    Posts : 203
    Join date : 2008-11-30

    Terminal strip

    Post by DynakitParts on Thu Nov 01, 2018 6:57 pm

    StevieRay,
                    Email to me your mailing address: dynakitparts@aol.com  and I will send you (2) of these brown (4) hole mounting strips.

    Kevin @ Dynakit
    avatar
    ViperZ

    Posts : 63
    Join date : 2010-03-26

    Re: Using all speaker taps -- new build.

    Post by ViperZ on Fri Nov 02, 2018 4:19 pm

    StevieRay wrote:Alas! -- I found these, but out of stock Crying or Very sad

    I use bananas exclusively now, so this is an option.

    I could make my own with Pamona bananas if I know where to get that phenolic board.......

    https://www.dynakitparts.com/shop/4-terminal-banana-jacks/

    I bought similar terminal strips from Kevin for my ST-70 many years ago, but he doesn't sell them any more, so I had to use 3-terminal strips on my MK-IIIs and not use 16-Ohm tap. I mean, how often do you use 16-Ohm taps, unless of course you have some nice monitors like Rogers ones.

    Maybe contact him and ask for expected delivery dates?

    (LOL, I see Kevin already responded Smile). Nice to see that we can get these new style terminal strips!!!)
    avatar
    Bob Latino
    Admin

    Posts : 2698
    Join date : 2008-11-26
    Location : Massachusetts

    Re: Using all speaker taps -- new build.

    Post by Bob Latino on Fri Nov 02, 2018 6:04 pm

    StevieRay wrote:

    I would like to be able to use all 3 (4/8/16 ohm) taps without having to rewire at times.


    You have a valid point IF you have speakers of all three impedances in your home. Understand that 95% of all speakers made today are either 4 or 8 ohm speakers so the 16 ohm tap now is almost never found anymore on modern USA made tube amps. All the VTA amps for the past two years now have 3 post binding posts and may be set up for any TWO impedances > 4 and 8 ohm, 4 and 16 ohm or 8 and 16 ohm. Rarely now do you see now a modern tube amp set up for all 3 impedances. Some still have just ONE pair of output binding posts. See below the rear of a modern $6000 Conrad Johnson Classic 62SE amp. (60 WPC like the VTA ST-120) It has one pair of output binding posts which normally come set up for 4 ohms but they will set up that one post for 8 or 16 ohms at the factory if you request the change. The McIntosh MC 2301 monoblocks (300 watts per monoblock and $22,000 for the pair) do have 3 pairs of binding posts but they are for 2, 4 and 8 ohms (no 16 ohms ?).

    Bob

    Conrad Johnson Classic 62SE rear



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