Can someone explain the Triode A470s Taps

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yalesmith
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Location: Orange County NY

Can someone explain the Triode A470s Taps

Post by yalesmith »

It looks like there are 2 taps blue/white and blue then a green/white and green (can be seen here http://www.triodeel.com/pdf/a470sdiag.pdf) what are differences? both are 4.3k Ohm i gather. I spoke to someone at Triode and he said the blue wires are plate leads and the green wires are UL screen taps. What are Plate leads? what is closer to what KF would have used


Thanks in advance!
Jana
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Re: Can someone explain the Triode A470s Taps

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martin manning
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Re: Can someone explain the Triode A470s Taps

Post by martin manning »

The ultralinear taps are usually at 43% of the way from the CT to the end of the primary (which are the normal plate leads), and they are connected to the screen grids when using that topology. For a non-ultralinear output stage you would use the outer Blue/Blue-White leads for a 4k3 primary. Using the Green/Green-White would give only 0.8k if the taps are at 43%.
yalesmith
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Location: Orange County NY

Re: Can someone explain the Triode A470s Taps

Post by yalesmith »

Which is typical of what is used in a Rocket? also in terms of sound, it theory, what would the characteristics be?

Thanks
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sliberty
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Re: Can someone explain the Triode A470s Taps

Post by sliberty »

A Rocket is not Ultralinear, so you would normally ignore the green pair. Also, many feel that Ultralinear is not that well suited to guitar amps (this is not a universal belief however). For example, some CBS Fenders used UL OT's, and many people felt that they sound like dog poo, and blamed the UL design for that. YMMV. But either way, on a Rocket, just use the Blue pair, and you will have a great sounding amp. Those 470A's really rock!
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