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    want another mod and have 3 original ST70

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    dynacophil

    Posts : 33
    Join date : 2010-10-26
    Age : 59
    Location : Berlin/Germany

    want another mod and have 3 original ST70

    Post by dynacophil on Mon May 30, 2011 3:17 pm

    Hi

    is it pc to ask about another mod made by another maker?

    If, I have an early VTA-mod ST70, I have a Sutherland-Mod ST-70 and a pile of 3 original ST70s, one already with aftermarket original layout board and replaced caps and rectifier.

    So 2 are left to be done something.... I also already have Dynakitpart-stainless chassis' waiting for a new project.

    I somehow read about that Welbourne Labs mu stage-Mod http://www.welbornelabs.com/st70.htm
    that seems interesting to me and wanted to know what others think about this design....

    Also (I can't find now, but have a link somewhere at home) I got the adress of some other modder that looked weird to me, becaause the used board was way bigger and was to mount outside what made the amp look like an oil-rig... If I find I'll ask about that too...

    best, Helge




    Westy56

    Posts : 58
    Join date : 2011-05-09
    Location : Albuquerque

    Re: want another mod and have 3 original ST70

    Post by Westy56 on Mon May 30, 2011 7:35 pm

    dynacophil wrote:Hi

    is it pc to ask about another mod made by another maker?

    Also (I can't find now, but have a link somewhere at home) I got the adress of some other modder that looked weird to me, becaause the used board was way bigger and was to mount outside what made the amp look like an oil-rig... If I find I'll ask about that too...

    best, Helge




    Is that board yellow?


    Steve

    Bob Latino
    Admin

    Posts : 2378
    Join date : 2008-11-27
    Location : Massachusetts

    Re: want another mod and have 3 original ST70

    Post by Bob Latino on Mon May 30, 2011 8:25 pm

    Hi,

    I don't know much about the Sutherland mod but beware of Welborne Labs. The Better Business Bureau of Denver,CO took away their BBB acreditation dues to numerous complaints of non-delivery of items over the past few years. Check some of the links below.

    http://www.bbb.org/denver/business-reviews/internet-selling-services/welborne-labs-in-littleton-co-90014438

    http://www.diyaudio.com/forums/everything-else/115516-welbourne-labs.html

    The Welborne driver board and parts set for the ST-70 is usually sold for $320. I see now that it is "on sale" for 20% off. ($256) (Hmmmm ... I wonder why? - It probably didn't sell well at $320?). In comparison, the VTA driver board and parts set is $90 year round.

    As to the Sutherland board ... I don't believe it is offered any more by Sutherland. If it is the board I am thinking of, it is a total SOLID STATE driver board with no tubes.

    Bob

    dynacophil

    Posts : 33
    Join date : 2010-10-26
    Age : 59
    Location : Berlin/Germany

    Re: want another mod and have 3 original ST70

    Post by dynacophil on Mon May 30, 2011 9:12 pm

    Thx for the warning Smile i read about in a AK-Thread yesterday and somebody was writing very (maybe a bit too) enthusiastic about this...

    http://www.audiokarma.org/forums/showpost.php?p=4692944&postcount=7

    The Sutherland-Mod is the one I have running in one of the amps (right - very solid state), as the VTA Board in a second.

    aliveatfive

    Posts : 7
    Join date : 2009-03-22

    Re: want another mod and have 3 original ST70

    Post by aliveatfive on Tue May 31, 2011 12:11 am

    I would not buy from Welborne. I had to wait many months for delivery of the board + kit + transformer. They were delivered weeks apart from each other. When everything was finally here, there was no manual to go along with all the assorted parts. All I had was a schematic, which I used to assemble the parts. The thing never biased properly and a loud humming noise came from the power transformer. By doing research, I found that the zener diodes that they use in the bias circuit are a really unapproved method of regulating bias current. Buyer beware!

    dynacophil

    Posts : 33
    Join date : 2010-10-26
    Age : 59
    Location : Berlin/Germany

    Re: want another mod and have 3 original ST70

    Post by dynacophil on Tue May 31, 2011 12:28 am

    Ok... was just an idea...

    mantha3

    Posts : 298
    Join date : 2010-11-10

    Re: want another mod and have 3 original ST70

    Post by mantha3 on Tue May 31, 2011 6:37 am

    If you have a VTA mod st70 then cool... Ya got to have one ST70 modded with a VTA.

    For other ideas... Maple Tree Audio is a nice place to check. I just got Loyd (Mapletree owner) to build me a passive pre amp. I think he sells his board. Looks nice!..

    No idea how it sounds... Loyd is a nice guy to do business with... Like the dudes of tubes4hifi

    Report on what ya do.


    mantha3

    Posts : 298
    Join date : 2010-11-10

    Re: want another mod and have 3 original ST70

    Post by mantha3 on Tue May 31, 2011 6:38 am

    PS - Google "mapletree Audio" and then check his site for products... He has a version of board he sells for ST70s. Again, no idea if it is any good. I think you just wanted ideas here.. So ya have it.


    dynacophil

    Posts : 33
    Join date : 2010-10-26
    Age : 59
    Location : Berlin/Germany

    Re: want another mod and have 3 original ST70

    Post by dynacophil on Tue May 31, 2011 1:19 pm

    Hi
    The VTA u see in my Avatar...

    can't find any prices on Mapletree Audio Site...
    best, Helge

    mantha3

    Posts : 298
    Join date : 2010-11-10

    Re: want another mod and have 3 original ST70

    Post by mantha3 on Tue May 31, 2011 5:43 pm

    You can call him at - (613) 387-3830

    Here is the board he has and I think you can pick the color -





    I hope I'm not ticking off anyone for mentioning this other company product... PS, You may want to have two VTA ST70s and use them as mono blocks...

    Here is his site -

    Mapletree[img]

    dynacophil

    Posts : 33
    Join date : 2010-10-26
    Age : 59
    Location : Berlin/Germany

    Re: want another mod and have 3 original ST70

    Post by dynacophil on Wed Jun 01, 2011 1:59 am

    mmmh
    the subject wire monoblocks out of st-70 has been discussed a lot and leads always to the same result: nope, no good idea.
    Sorry, sure I could call, but I guess I'am ±8 hours ahead, can't call US from job...

    mantha3

    Posts : 298
    Join date : 2010-11-10

    Re: want another mod and have 3 original ST70

    Post by mantha3 on Wed Jun 01, 2011 6:02 am

    Sure, no biggie. If ya never call Lloyd it won't bum me out. Just ideas for ya. I think you were just looking for some ideas on things to tinker with..

    Assuming I'm right.. I found this one a few months ago and it was interesting... Read this link:

    The Ultimeate Dynaco ST-70 Mod - Remote Sensing Feedback

    Not an expensive tweek. Again, just tossing ideas out.

    Have fun and post pics/report on what works and what may not.

    Adios

    baddog1946

    Posts : 304
    Join date : 2010-02-04
    Location : Costa Rica

    Re: want another mod and have 3 original ST70

    Post by baddog1946 on Wed Jun 01, 2011 6:43 am

    Check out the dynamutt and KTA driver boards they are usually for sale on eBay.

    j4570

    Posts : 141
    Join date : 2010-08-31

    Re: want another mod and have 3 original ST70

    Post by j4570 on Wed Jun 01, 2011 7:55 am

    I don't think you can the ST70 in mono with a VTA board, as you only put the switch in there as a place holder.

    Anyway, I agree, nearly every briding amp I ever heard sounded better in stereo. Most of that experience comes from car stereo, and it was popular at one time. Now running two mono channels for bass is different than briding the amp. Most bridged amps heat up a lot (though I wouldn't think a tube amp would care).

    JW

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