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    Just obtain a ST-70 built by Bob Latino

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    myounger1930

    Posts: 9
    Join date: 2009-08-31
    Age: 52
    Location: Memphis TN

    Just obtain a ST-70 built by Bob Latino

    Post by myounger1930 on Tue Dec 29, 2009 12:37 am

    What upgrades can be done to this system. Current setup is
    AudioNova DAC/Amp connected to a shuttle PC , DAC connected to a Woo Audio headphone/preamp connect to ST-70 ,speakers Klispch Hersesy 's ...

    LEVLHED

    Posts: 21
    Join date: 2009-10-26

    Re: Just obtain a ST-70 built by Bob Latino

    Post by LEVLHED on Tue Dec 29, 2009 10:23 am

    I just changed out the Electro Harmonix EL34's for Genalex Gold Lion KT66's. A pretty big difference in sound! In hindsight I probably should have just changed those first.

    Other than that there's a mind boggling number of choices for the 12AT7's affraid (assuming you have the high gain board like me). I am currently running an RCA black plate in the middle and some Siemens triple mica's on the sides. The Siemens were a little pricey and I got the RCA for xmas, but I assume it wasn't necessarily *cheap* either. It's all relative though, isn't it?
    Many people seem to like the Mullards. The midrange is awesome but the highs were too rolled off for my taste. YMMV Suspect

    Bob Latino
    Admin

    Posts: 1958
    Join date: 2008-11-26
    Location: Massachusetts

    Re: Just obtain a ST-70 built by Bob Latino

    Post by Bob Latino on Tue Dec 29, 2009 10:46 am

    myounger1930 wrote:What upgrades can be done to this system. Current setup is
    AudioNova DAC/Amp connected to a shuttle PC , DAC connected to a Woo Audio headphone/preamp connect to ST-70 ,speakers Klispch Hersesy 's ...

    Hi myounger1930,

    Virtually everything on that amp is upgraded already be it the power transformer, B+ DC power storage, stainless chassis, driver board etc, etc. I believe that your amp already has the power supply upgrade capacitors and the Russian PIO main coupling capacitor upgrade. There is really nothing left to do but, as LEVELHED mentioned, roll tubes.

    The Gold Lion KT66 output tubes are really great in that amp. I like the Mullard CV4024 (12AT7 equivalent) in the 3 driver positions. They are easier to source NOS than the RCA blackplates. As for a rectifier > An inexpensive GZ34 is the Ruby GZ34. I like it better than either the Sovtek or JJ equivalents. If you want to experiment with a solid state rectifier try the Weber Copper Cap WZ68. No tube rectifier will flow as much current as the Weber WZ68 at high current demands. At higher volume levels I notice a touch more bass impact from my VTA ST-70 when using the Weber WZ68.

    Bob

    myounger1930

    Posts: 9
    Join date: 2009-08-31
    Age: 52
    Location: Memphis TN

    St-70

    Post by myounger1930 on Tue Dec 29, 2009 1:53 pm

    Thanks for the tube rolling advice,
    I dont beleive the amp I have as the upgraded PS or Rusiiam caps, so can i still use
    the tubes mentioned? Also is it possible to over drive with the two pre-amps i am using feeding
    into ST-70? DAC/Preamp- Woo Preamp - ST70 . I will try to post pictures

    myounger1930

    Posts: 9
    Join date: 2009-08-31
    Age: 52
    Location: Memphis TN

    Pictures

    Post by myounger1930 on Tue Dec 29, 2009 2:01 pm

    http://i19.servimg.com/u/f19/14/69/13/63/12-29-14.jpg
    http://i19.servimg.com/u/f19/14/69/13/63/12-29-16.jpg
    http://i19.servimg.com/u/f19/14/69/13/63/12-29-17.jpg
    http://i19.servimg.com/u/f19/14/69/13/63/12-29-18.jpg


    Last edited by myounger1930 on Tue Dec 29, 2009 2:05 pm; edited 1 time in total

    Bob Latino
    Admin

    Posts: 1958
    Join date: 2008-11-26
    Location: Massachusetts

    Re: Just obtain a ST-70 built by Bob Latino

    Post by Bob Latino on Tue Dec 29, 2009 2:03 pm

    Hi,

    You can drive that amp with virtually any preamp or high level input souce with a volume control. I haven't found or had anyone tell me of any "mismatch" issue when the VTA ST-70 was driven by ANY source with a volume control.

    Sure - post up some photos of your amp and/or your entire system. If you look at the stickys above we have an area where members can post photos of their system. The only issue is that you will have to host the photos on another web site and then link to them.

    Bob

    myounger1930

    Posts: 9
    Join date: 2009-08-31
    Age: 52
    Location: Memphis TN

    ST-70

    Post by myounger1930 on Tue Dec 29, 2009 2:17 pm

    I have volume controls on both preamps(DAC and Woo) that allow me to really crank up the volume...
    I am new to this hobby but already love the sound - starting to rebuild a ST-35,
    Current set-up Itunes lossless files out of a shuttle PC feeding Peachtree Audionova DAC/Pre-amp/Amp into
    a WooAudio2 Headphone/Preamp (bg470u/160v,bg220u/200v caps) out to the ST-70

    LEVLHED

    Posts: 21
    Join date: 2009-10-26

    Re: Just obtain a ST-70 built by Bob Latino

    Post by LEVLHED on Tue Dec 29, 2009 2:45 pm

    there really shouldn't be any need to put the Woo headphone amp in there too? Just go from the Peachtree to the ST-70. That alone should improve the sound, I can't see any reason to run two preamps in line like that.

    Yes, you can change the tubes regardless of the other parts.

    Do you know what tubes are currently in your ST-70?

    edit:
    actually isn't that Peachtree an integrated amplifier? Are you just using some sort of pre out on it?
    Please detail what you have and how you are hooking it up.

    myounger1930

    Posts: 9
    Join date: 2009-08-31
    Age: 52
    Location: Memphis TN

    ST-70

    Post by myounger1930 on Tue Dec 29, 2009 2:59 pm

    Thanks - I will get the tubes specs tonight and exactly how I have it wired.
    I have hooked it several differeny ways. With the Woo and with out . I figured the more tubes I ran it thru the higher i could crank it up... the Hersesy HBR speakers handle all i throw at it - ST-70 and the ST35. I mainly want the Peachtree for the DAC
    and bypass the amp section. i hooked up so i could control the volume with the preachtree remote. The Woo has 4 inputlines in and one output line. the peachtree has control line input and line level input as welll . I have hooked up both ways...

    LEVLHED

    Posts: 21
    Join date: 2009-10-26

    Re: Just obtain a ST-70 built by Bob Latino

    Post by LEVLHED on Tue Dec 29, 2009 3:21 pm

    ah I get it, you need the DAC on the Peachtree and I'm certain the remote would be considered essential as well. Yeah, I would still pull the Woo Audio preamp out of the loop even though it looks like it is a nice preamp itself. I guess you can let your ears decide what you like better?
    To me it doesn't make sense to have two preamp's in line like that, I think it would just add more noise than anything really useful.

    I'd be tempted to just sell the Woo and reinvest the money elsewhere!
    Heck, sell both the Peachtree and Woo to get a dedicated preamp and DAC?

    The USA Dared seller sells the Dared SL-2000A preamp with remote + a USB DAC.
    I love my Dared preamp with my VTA ST-70!

    myounger1930

    Posts: 9
    Join date: 2009-08-31
    Age: 52
    Location: Memphis TN

    ST-70

    Post by myounger1930 on Tue Dec 29, 2009 3:26 pm

    If sell the Woo and Peachtree what would you reccomend for a DAC?

    LEVLHED

    Posts: 21
    Join date: 2009-10-26

    Re: Just obtain a ST-70 built by Bob Latino

    Post by LEVLHED on Tue Dec 29, 2009 3:50 pm

    really what I'd do is just goto ebay and search for Dared under electronics and take a look at the SL-2000A. He sells it with a USB DAC too! It's just a basic solid preamp with the added benefit (IMO) of using 12AT7's which lets you do all sorts of swapping around with the ST-70.

    I have no idea how "quality" the DAC is, but it can't be that bad.
    Myself, I'm just using an Audiotrak Maya44 USB soundcard I had left over from previous projects. Eventually I'll be getting an ASUS Xonar STX internal sound card for my HTPC/music server.

    I bought my Dared used.

    As with all of this though there are any number of directions to go and it pays to do your research and decide for yourself! There is no "best" anything.

    Les Lammers

    Posts: 5
    Join date: 2010-02-02

    Re: Just obtain a ST-70 built by Bob Latino

    Post by Les Lammers on Wed Feb 03, 2010 4:14 am

    myounger1930 wrote:If sell the Woo and Peachtree what would you reccomend for a DAC?

    New guy to the forum here.

    Google MHDT Labs Havana. There is no 'best' but this is really, really good. Google Bob Crites for Heresy mods.

    Preamp? I recently got a very clean Marantz 1060 30 wpc integrated that can be also used as a pre. I am driving a good 6BQ5 amp with it and the sound is excellent. It also has a well regarded phono stage and tone controls. I will have the 1060 completely 'refreshed' caps etc. and replace the 6BQ5 with a ST-70. As always YMMV.

    Bob Latino
    Admin

    Posts: 1958
    Join date: 2008-11-26
    Location: Massachusetts

    Re: Just obtain a ST-70 built by Bob Latino

    Post by Bob Latino on Wed Feb 03, 2010 6:19 am

    Preamp? I recently got a very clean Marantz 1060 30 wpc integrated that can be also used as a pre

    Many of the Japanese built (Pioneer, Sansui, Sony, Kenwood, Marantz etc.) receivers of the 1970's and 1980's have two "U" shaped pins on the back of the preamp that may be used to separate the amp from the preamp sections of the receiver. When you pull the two pins (one for each channel) you wind up with two "PRE OUT" and two "AMP IN" RCA connectors. This allows you to now use the amp and preamp sections of your receiver separately. The nice thing is that many of the lower powered Japanese receivers can be had used on Ebay for less than $100. You can get yourself a nice serviceable "preamp" to use with your Dynaco tube amp for low bucks. Check first, however, before you buy, that the receiver DOES HAVE this nice feature because they all don't.

    Bob

    Les Lammers

    Posts: 5
    Join date: 2010-02-02

    Re: Just obtain a ST-70 built by Bob Latino

    Post by Les Lammers on Wed Feb 03, 2010 6:34 am

    That is exactly why I bought it. Very Happy The 1060 is the sweet spot. The going price for a near mint sample is $100-$125. I suggest getting it stock and re-doing it yourself or sending it to a tech who really knows this piece. That is what I am going to do.

    I also got a Sanusi AU555 mint in the box and will compare the two. However, I think the phono stage in the Marantz will be hard to beat. These are very well built machines and the outputs are capacitor coupled. If you decide to do some work on your Dyna, you still have a sweet sounding amp to use while you work. Very Happy

    Bob, I went with the lower power units because of the simple design and do not get hot...just warm to the touch.

    Both of these and the Sansui Au555a have the pre/main option. I am sure there are others too.

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