New build Low volume and LarMar issue

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rooster
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Re: New build Low volume and LarMar issue

Post by rooster »

Woah. Swapping the OT primaries is not the problem. The amp would scream/howl at much lower volumes the 1/2. :lol:

Those resistors you call the 'swamp' resistors are always best place on the socket - as close to the pin as possible. And that may be your slight noise issue. When done correctly, the LarMar MV is absolutely quiet.
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yalesmith
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Re: New build Low volume and LarMar issue

Post by yalesmith »

I just swapped the OT wires and it works perfect. As far as the swamper resistors I always thought that it should be by the pin but the larmar instructions specifically calls for them to be put at the pot. Any thoughts?

As far as the LarMar is concerned, is really works well, i'll be honest cant really tell the difference. it works just as good if not better than the air-brake all things considered. I am really happy with this design...ingenious!
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rooster
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Re: New build Low volume and LarMar issue

Post by rooster »

Wow. So your 'slight noise' issue was caused by the reversed primaries? Hm, OK. I guess everything is realtive, including slight noise.

Here's a pic of the LarMar hookup that I have worked from. It clearly describes the grid resistors (your 'swamp resistors') as being where they typically are, which is on the tube socket pin.
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Most people stall out when fixing a mistake that they've made. Why?
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rooster
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Re: New build Low volume and LarMar issue

Post by rooster »

BTW, Larry of Larry Amps, a rather brilliant gentleman IMO, came up wtih the implementation of the LarMar MV.

Where are you finding a drawing suggesting hanging the grid resistors off the dual pot? I hope it's not from this site?
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yalesmith
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Re: New build Low volume and LarMar issue

Post by yalesmith »

I was using the following: Thanks for the input as i would agree it would make sense to be put at the tube
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JazzGuitarGimp
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Re: New build Low volume and LarMar issue

Post by JazzGuitarGimp »

Glad to hear you got it working, yale!
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