18W SuperLite TMB a little too harsh

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Piamp
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18W SuperLite TMB a little too harsh

Post by Piamp »

Hi!
Thanks for all the ressources here :)
I built a 18W SuperLite TMB, and i think it needs some tweakings.
I did not really like the gain/vol combination so i dumped the volume pot and wired a crossline master volume instead, it's much better now with nice PI distorsion.
But i find it a little too harsh, if no eye piercing....treeble needs to be way low even on the neck pickup of my LP.
Any tweak i could try ? A 50pf accross the pi did nothing :)
Also i get a lot of hiss, changed tubes, still here !
0 x

thomas22
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Re: 18W SuperLite TMB a little too harsh

Post by thomas22 »

Lower Coupling Cap Values – If you’re using 0.022µF or larger coupling caps in the preamp or PI, try reducing them to 0.01µF or even 0.0047µF to cut some of the high-end fizz.
Grid Stopper Resistors – Increase the grid stopper resistors on the preamp tubes, especially on V1 (try 68kΩ to 100kΩ on the input stage). This can roll off some high frequencies.
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Bieworm
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Re: 18W SuperLite TMB a little too harsh

Post by Bieworm »

Piamp wrote:
Sat 03/15/25 12:21 pm
Hi!
Thanks for all the ressources here :)
I built a 18W SuperLite TMB, and i think it needs some tweakings.
I did not really like the gain/vol combination so i dumped the volume pot and wired a crossline master volume instead, it's much better now with nice PI distorsion.
But i find it a little too harsh, if no eye piercing....treeble needs to be way low even on the neck pickup of my LP.
Any tweak i could try ? A 50pf accross the pi did nothing :)
Also i get a lot of hiss, changed tubes, still here !
Let’s start with the speaker. If you’re using a V30 or G12H30 70th anniversary series that could be enough to experience a harsh amp. IME the SL is not a harsh amp at all
1 x
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