prefered voltages?

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Roe
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prefered voltages?

Post by Roe » Thu May 31, 2012 9:56 am

What kind of voltages do you prefer in your 45/100s (at idle and when running)? Having tried voltages from 480 to 560v (at idle) in 4 different jtm45/100s w/kt66s, I think I prefer the sound of plate voltages around 520-530v. However, the higher voltages give a nice, punchy response though.

The marstran 1204-43 seem to sag quite a bit under load (like the originals did). When I tried the other day, one of my amps saged 40v when playing a little ac/dc (and even more when running flat out). Do the metro -43 sag this much?

Finally, what kind of choke are you running? I'm using the RS in one of my 45/100s and its 690ohm resistance brings down the screen voltage quite a bit (around 400v when running flat out, although its 525-530 at idle)
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neikeel
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Re: prefered voltages?

Post by neikeel » Thu May 31, 2012 10:38 am

Roe wrote:What kind of voltages do you prefer in your 45/100s (at idle and when running)? Having tried voltages from 480 to 560v (at idle) in 4 different jtm45/100s w/kt66s, I think I prefer the sound of plate voltages around 520-530v. However, the higher voltages give a nice, punchy response though.

The marstran 1204-43 seem to sag quite a bit under load (like the originals did). When I tried the other day, one of my amps saged 40v when playing a little ac/dc (and even more when running flat out). Do the metro -43 sag this much?

Finally, what kind of choke are you running? I'm using the RS in one of my 45/100s and its 690ohm resistance brings down the screen voltage quite a bit (around 400v when running flat out, although its 525-530 at idle)
Not been that forensic (although perhaps I should :oops: ).
Recent gigs quite small indoor (< 250 people) so been using 50watters or my 18w. We have x3 outdoors to do in next month so will be taking the 45/100. My metro had an early -43 with the higher voltages. I am really happy with it although most the stuff we are playing at the moment (funk, pop and indie) I run in the clean range with a bit of fuzz or boost for dirty stuff but more often a bit of slap back or a touch of compression. I like the thick punchy response of this amp with the GECs.
Neil

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