18 watt Superlite TMB Reverb

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Re: 18 watt Superlite TMB Reverb

Post by Bieworm »

JMPGuitars wrote:
Mon 08/09/21 7:46 am
Sounds great!

When you make your reverb tank bag, live a tiny little bit of room height-wise. You probably will want to slide a piece or two of cardboard in there the length/width of the tank (covering the tank opening).

Thanks,
Josh
I learned a lot about the behavior of tanks. I always put a long piece of adhesive foam on top of the tank to prevent resonance and 2 long pieces of that foam on the bottom of the combo to suspend the tank from the cab. The bottom is closed with aluminiumfoil covered 2mm plexi sheet, bolted to the tank.
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Re: 18 watt Superlite TMB Reverb

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After playing with it I feel the amp is too bass heavy, even on the bright switch setting. The speaker buzzes.. very annoying. I built the amp playing a telecaster, but now I played my jazzmaster and the buzz appeared...
I was thinking to swap the .022uf coupling cap between V1a and the gain pot with a .0047uf. Good idea to start?
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Re: 18 watt Superlite TMB Reverb

Post by JMPGuitars »

Maybe. Also maybe try a different speaker first?
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Re: 18 watt Superlite TMB Reverb

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Bieworm wrote:
Tue 08/10/21 3:34 pm
After playing with it I feel the amp is too bass heavy, even on the bright switch setting. The speaker buzzes.. very annoying. I built the amp playing a telecaster, but now I played my jazzmaster and the buzz appeared...
I was thinking to swap the .022uf coupling cap between V1a and the gain pot with a .0047uf. Good idea to start?
Is the owner still on about tilt-back legs? Decoupling the bottom of the combo from the floor when it is tilted may affect the low end, so something to consider. I would also be inclined to consider the speaker choice but also trimming the coupling cap down. Do you have a current schematic, as you built the amp?
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Re: 18 watt Superlite TMB Reverb

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colossal wrote:
Wed 08/11/21 10:31 pm
Bieworm wrote:
Tue 08/10/21 3:34 pm
After playing with it I feel the amp is too bass heavy, even on the bright switch setting. The speaker buzzes.. very annoying. I built the amp playing a telecaster, but now I played my jazzmaster and the buzz appeared...
I was thinking to swap the .022uf coupling cap between V1a and the gain pot with a .0047uf. Good idea to start?
Is the owner still on about tilt-back legs? Decoupling the bottom of the combo from the floor when it is tilted may affect the low end, so something to consider. I would also be inclined to consider the speaker choice but also trimming the coupling cap down. Do you have a current schematic, as you built the amp?
Thanks! I used the latest schematic in the Downloads area, just added reverb.
But I think the problem was something else. It was the position it stood in the room. It's a laminate floor. When I was preparing for the solution to the problem yesterday I noticed the buzz was gone. The amp stood a few meters from the spot It was before, when It buzzed. Maybe a hollow part of the floor was the cause
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Re: 18 watt Superlite TMB Reverb

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Did some experimenting and I like it a LOT!!
Here's what I did: initially I installed the bright-fat switch. After finding it not fat enough to be very different I swapped the 1uf additional/switch-in cathode bypass cap with a 2.2uf. That was a lot more what I wanted. Overall the amp is really bassy , even on the bright setting. I like that, but not for every situation. The switch I used for the bright-fat switching happens to be a DPDT mini toggle. I only used 1 side for the switching, so there was this spare side waiting to get involved.
Now, I put a .01uf cap in series with the .022uf coupling cap before the gain pot.. but it can be switched out when the fat switch is activated. This means that on the fat setting there is a .022uf coupling cap + the extra 2.2uf on the cathode over V1a, whilst on the bright setting there is only a .047uf cathode bypass cap and the series .022uf+ .01uf = .0068uf.
Sounds really great!!!
https://www.dropbox.com/s/smoka9iyloal4 ... 10812?dl=0
https://youtu.be/uLRlic0Alac
Last edited by Bieworm on Thu 08/12/21 10:58 pm, edited 1 time in total.
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Re: 18 watt Superlite TMB Reverb

Post by JMPGuitars »

Sounds great! A really nice variety of tone (and the demo only scratched the surface of the dirt it should be capable of). Perhaps now you understand why I like ZP's Superlite TMB circuit so much. ;)
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Re: 18 watt Superlite TMB Reverb

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JMPGuitars wrote:
Thu 08/12/21 3:32 pm
Sounds great! A really nice variety of tone (and the demo only scratched the surface of the dirt it should be capable of). Perhaps now you understand why I like ZP's Superlite TMB circuit so much. ;)
I will build myself one too!!! I want to keep it as is... great little amp!!!
And it's dirty all right!!!
Vol was on 2 for the clip , gain not even max
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Re: 18 watt Superlite TMB Reverb

Post by colossal »

Great job. Sounds really nice.
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