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Author Topic: Barely any sound in the left channel [resolved]  (Read 1126 times)

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Offline Jimb0

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Barely any sound in the left channel [resolved]
« on: July 09, 2020, 08:38:02 AM »
Getting some static and nearly no sound in left channel. Voltages checked out good. I also tried all three inputs same issue* Edit
« Last Edit: July 17, 2020, 04:53:24 PM by Paul Birkeland »

Offline Thermioniclife

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Re: Barely any sound in the left channel
« Reply #1 on: July 09, 2020, 09:12:16 AM »
Did you try all three inputs?
Lee R.

Offline Paul Birkeland

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Re: Barely any sound in the left channel
« Reply #2 on: July 09, 2020, 09:13:40 AM »
I would start by resoldering all of the joints in the amp.  If that doesn't resolve the issue, try connecting a jumper between the upper and lower middle lugs on the volume pot to see if that brings back the left channel.
Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man

Offline Jimb0

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Re: Barely any sound in the left channel
« Reply #3 on: July 09, 2020, 09:36:21 AM »
Did you try all three inputs?

Yes, sorry I meant I tried different inputs in my first post
« Last Edit: July 09, 2020, 09:41:03 AM by Jimb0 »

Offline Jimb0

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Re: Barely any sound in the left channel
« Reply #4 on: July 09, 2020, 09:40:54 AM »
I would start by resoldering all of the joints in the amp.  If that doesn't resolve the issue, try connecting a jumper between the upper and lower middle lugs on the volume pot to see if that brings back the left channel.

Sure I will try resoldering the joints. Also, how do I connect the jumper on the stepped attenuator? Which lugs will I be connecting?

Offline Paul Birkeland

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Re: Barely any sound in the left channel
« Reply #5 on: July 09, 2020, 12:57:32 PM »
Also, how do I connect the jumper on the stepped attenuator? Which lugs will I be connecting?
try connecting a jumper between the upper and lower middle lugs on the volume pot
Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man

Offline Jimb0

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Re: Barely any sound in the left channel
« Reply #6 on: July 17, 2020, 08:59:06 AM »
Hi PB. Just got some time to work on this. So to be clear am I connecting Q3U and Q3L, Q8U and Q8L, Q11U and Q11L? Sorry if I'm not understanding this

Offline Paul Birkeland

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Re: Barely any sound in the left channel
« Reply #7 on: July 17, 2020, 09:18:08 AM »
Wait, what? Did this work before the Two-Quiet?
Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man

Offline Jimb0

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Re: Barely any sound in the left channel
« Reply #8 on: July 17, 2020, 09:21:02 AM »
I skipped the normal pots and upgraded it with the two quiet

Offline Paul Birkeland

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Re: Barely any sound in the left channel
« Reply #9 on: July 17, 2020, 09:53:47 AM »
So, what I would have you do to debug the stock amp isn't all that easy to do on the 2-Quiet.  In fact, one could ruin the coarse switch attempting to do the debugging in the same way that debugging the amp with the pots could easily be done.

4U and 12U could be connected together to mostly ascertain whether the attenuators/input wiring are the problem or something else.
Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man

Offline Jimb0

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Re: Barely any sound in the left channel
« Reply #10 on: July 17, 2020, 10:33:02 AM »
Thanks PB I'll try that out

Offline Jimb0

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Re: Barely any sound in the left channel
« Reply #11 on: July 17, 2020, 10:42:48 AM »
I'm getting sound in both channels when 4U is connected to 12U

Offline Paul Birkeland

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Re: Barely any sound in the left channel
« Reply #12 on: July 17, 2020, 11:53:27 AM »
Take that jumper out and jumper Q1 to Q5.

If you still have sound in both channels, then there's an issue between the attenuator and the RCA jacks.

If you lose one channel (which I think you will), then you have an issue with the build of the attenuator.
Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man

Offline Jimb0

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Re: Barely any sound in the left channel
« Reply #13 on: July 17, 2020, 01:49:50 PM »
Thanks PB. Indeed I lost sound in the left channel again
« Last Edit: July 17, 2020, 01:51:38 PM by Jimb0 »

Offline Jimb0

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Re: Barely any sound in the left channel
« Reply #14 on: July 17, 2020, 02:16:55 PM »
I had the red wire from the fine switch bottom lug going to the bottom lug of the course switch when it should've been going to terminal 1. I can hear the sound on both sides now, however I'm getting mild hiss/static in both channels. Did I mess up the Two Quiet or is this something else?