New VTA driver boards. To upgrade or not

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New VTA driver boards. To upgrade or not

Postby thisisjay » Tue Dec 18, 2012 5:10 pm

I have a ST-120 that is about 3 years old. It still has the VTA driver board that came with the kit. I see now that there are new driver boards out that use a constant current source rather than the old trimpot controlled AC balance system. I have 2 questions:

1. Is the constant current source a big enough step up to warrant an upgrade.

2. If it is worth upgrading, should I install the board that takes 6sn7's?
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Re: New VTA driver boards. To upgrade or not

Postby battradio » Tue Dec 18, 2012 10:37 pm

Image
This is the schematic of the new board , Buy one of shannons Diytube ST 70 boards board it sounds beter .
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Re: New VTA driver boards. To upgrade or not

Postby thisisjay » Wed Dec 19, 2012 9:57 am

Fail! I just came onto Pepsi Board asking about a new flavor of Coke. Not likely to get an unbiased opinion here. I withdraw the question.
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Re: New VTA driver boards. To upgrade or not

Postby mesherm » Wed Dec 19, 2012 3:36 pm

I have built several amps with the older VTA driver board and also with Shannon's driver board.
As long as you have the phase inverter section properly adjusted I would keep the old VTA in place.
I doubt you would hear any difference with a CCS on the PI tail over a properly adjusted all resistor PI. Tube rolling would be a more effective upgrade soundwise.
Mike's N-1 Rule: When looking for N number of components to finish a job, you have a 95% chance of only finding N-1 of them.
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