new build 36lite with vvr
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Re: new build 36lite with vvr
Would this do? Furman seems unavailable/ expensive over here
https://ie.farnell.com/phonapart/cs929- ... dp/3530988
They also sell handy things like metal film resistors etc...
https://ie.farnell.com/phonapart/cs929- ... dp/3530988
They also sell handy things like metal film resistors etc...
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Re: new build 36lite with vvr
They block me from viewing their site, but if it's filtering the mains, then it should probably help.chaliapin wrote: ↑Wed 03/08/23 5:46 amWould this do? Furman seems unavailable/ expensive over here
https://ie.farnell.com/phonapart/cs929- ... dp/3530988
They also sell handy things like metal film resistors etc...
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Re: new build 36lite with vvr
6 way, 2m mains conditioner and radio frequency interference filter for home cinema and hi-fi.
Contains a powerful mains conditioning filter
Reduces or eliminates mains interference
Helps to enhance sound and picture quality
Incorporates surge protection
Mains cable shielded with aluminium foil
Applications
Sent from my SM-J600FN using Tapatalk
Contains a powerful mains conditioning filter
Reduces or eliminates mains interference
Helps to enhance sound and picture quality
Incorporates surge protection
Mains cable shielded with aluminium foil
Applications
Sent from my SM-J600FN using Tapatalk
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Re: new build 36lite with vvr
Mains conditioner and ruby mod in. Not replaced input resistors yet. Amp seems a little better behaved up to halfway amp volume (guitar ON FULL), no popping or static or particular humming for the ten minutes I managed to play earlier. At half volume there is a a little dirt in the sound but nothing you'd call overdrive or crunch. It's pretty loud at that point but I don't have much here to compare it to and say if it's producing the right volume. Turning up further gives unmusical harmonics with the distortion along with fartiness...
Sent from my SM-J600FN using Tapatalk
Sent from my SM-J600FN using Tapatalk
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Re: new build 36lite with vvr
Take new voltages and post them all.
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Re: new build 36lite with vvr
Latest voltages marked on the left with a line. Little significant difference. As I said before I have a pair of output tubes giving only 20mv on the grid but ive paired them with leakier ones so combined giving 40-60mv.
AC varies here.
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AC varies here.
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Re: new build 36lite with vvr
To recap what I think I've read so far...
You probably regret making a 36W instead of an 18W. You were considering a PPIMV to reduce the volume/headroom.
2 of your 4 power tubes are likely faulty.
You're unhappy with the distortion sound from the amp.
I can't read the voltages, the image is too small.
The only reasonable advice I can give you is to take the 2 GOOD tubes, and ditch the 2 bad tubes. Rewire the amp as an 18W and get the voltages where they need to be. Listen to it. It will probably sound a lot closer to what you want, and give you the dirt you want, with more usable volume levels.
This amp drives the power tubes to get that sweet distortion sound. If you're power tubes are problematic, you'll never get a good sound.
You probably regret making a 36W instead of an 18W. You were considering a PPIMV to reduce the volume/headroom.
2 of your 4 power tubes are likely faulty.
You're unhappy with the distortion sound from the amp.
I can't read the voltages, the image is too small.
The only reasonable advice I can give you is to take the 2 GOOD tubes, and ditch the 2 bad tubes. Rewire the amp as an 18W and get the voltages where they need to be. Listen to it. It will probably sound a lot closer to what you want, and give you the dirt you want, with more usable volume levels.
This amp drives the power tubes to get that sweet distortion sound. If you're power tubes are problematic, you'll never get a good sound.
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Re: new build 36lite with vvr
Stupid tapatalk app shrunk the photo.
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Re: new build 36lite with vvr
Ok I think I've finally made it. Josh diagnosis of bad ac power was totally right, unfortunately the power conditioner does f all. The intermittent awful distortion was the motor of the washing machine coming on and off...
Sorted through until I had 4 power tubes I was happy with. Very happy with the spiky cleans with the full 36 Watts.
Fitted the vvr to the whole amp, to be honest I'm not bothered about chasing super low volume distortion, I just play cleaner when I want it quieter. I like the vvr a lot though.
Also added the pp-se mod which is basically a ppmv for one side of the power section. Love this mod too, reduces overall volume quite a lot and changes the flavour in a tweedy early gibson feel .
Still have slight microphonic issues with the chassis in the combo cab but I've no more time to investigate or build boxes so it's just sat on top for the moment...
Sorted through until I had 4 power tubes I was happy with. Very happy with the spiky cleans with the full 36 Watts.
Fitted the vvr to the whole amp, to be honest I'm not bothered about chasing super low volume distortion, I just play cleaner when I want it quieter. I like the vvr a lot though.
Also added the pp-se mod which is basically a ppmv for one side of the power section. Love this mod too, reduces overall volume quite a lot and changes the flavour in a tweedy early gibson feel .
Still have slight microphonic issues with the chassis in the combo cab but I've no more time to investigate or build boxes so it's just sat on top for the moment...
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Re: new build 36lite with vvr
Nice! Glad to see you made progress.
Did you use a filtered inlet, or just a filtered power strip? I like to use both.
You should post updated voltages and see what your power tube dissipation is now.
It's possible some of your tubes just happen to be microphonic, but it's also possible that the voltages are increasing a tubes tendency towards microphonics. You can tap each tube with a chopstick and see if any of them respond louder or differently than the others. With the amp on so you can hear it.
Did you use a filtered inlet, or just a filtered power strip? I like to use both.
You should post updated voltages and see what your power tube dissipation is now.
It's possible some of your tubes just happen to be microphonic, but it's also possible that the voltages are increasing a tubes tendency towards microphonics. You can tap each tube with a chopstick and see if any of them respond louder or differently than the others. With the amp on so you can hear it.
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Re: new build 36lite with vvr
Thanks josh.
Honestly I'm surprised I still have any tubes left after the hours already spent tapping and listening...
I used just the filter strip. I'll order a filtered inlet next time I order anything.
I'll post new voltages but I doubt they've changed much from my last post a while ago. Haven't done much since I finally noticed that the timing of the nasty distortion was very similar to that of the washing machine turning and pausing...
Honestly I'm surprised I still have any tubes left after the hours already spent tapping and listening...
I used just the filter strip. I'll order a filtered inlet next time I order anything.
I'll post new voltages but I doubt they've changed much from my last post a while ago. Haven't done much since I finally noticed that the timing of the nasty distortion was very similar to that of the washing machine turning and pausing...
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Re: new build 36lite with vvr
Still got a sibilant metallic nastiness getting into the sound. Nothing in these voltages causing me trouble is there?
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Re: new build 36lite with vvr
I'm assuming there's nothing suspicious in the above voltages? At this point considering getting an amp tech to look at it...
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Re: new build 36lite with vvr
What are your cathode resistor values for the power tubes? 150Ω? Have you calculated your dissipation? If it's 150Ω, then you should be okay there.
V1 plate voltages are low.
Share a sample of the audio problem. Descriptions aren't often enough.
What are your power transformer specs?
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Re: new build 36lite with vvr
Thanks josh. Cathode resistor is 150 yes.
Pt is a danbury pt04. I can't find anything on the net but I think Barry at ampmaker used to supply them in his kits. Attached the sheet I got with it plus tea stains...
I tried to record a couple of clips but the volume distorts my phone mic. I'll try to sort something else out. It's not as bad when the chassis is on top of the combo rather than bolted in. It's in the treble, sounds like sitar-like fret buzz but it isn't.
I'm thinking could be lead dress, hopefully borrowing a looper pedal so I can chopstick and listen at the same time.
Pt is a danbury pt04. I can't find anything on the net but I think Barry at ampmaker used to supply them in his kits. Attached the sheet I got with it plus tea stains...
I tried to record a couple of clips but the volume distorts my phone mic. I'll try to sort something else out. It's not as bad when the chassis is on top of the combo rather than bolted in. It's in the treble, sounds like sitar-like fret buzz but it isn't.
I'm thinking could be lead dress, hopefully borrowing a looper pedal so I can chopstick and listen at the same time.
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Re: new build 36lite with vvr
Ok this is another phone recording. The vvr is on 8, I know that's not what you want but I'm getting the same high pitched ringing at full power but the phone recording falls to pieces at that volume. I switched both pre valves, no change.
https://vimeo.com/865899860
Holding the tubes doesn't get rid of the high pitched ringing which you can hear after the guitar begins to fade.
https://vimeo.com/865899860
Holding the tubes doesn't get rid of the high pitched ringing which you can hear after the guitar begins to fade.
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Re: new build 36lite with vvr
Does the same noise come through with other guitars?
Have you ruled out any ground loops? Have you tried that with the VVR completely bypassed?
Have you tried different power tubes?
Ruby mod?
Have you ruled out any ground loops? Have you tried that with the VVR completely bypassed?
Have you tried different power tubes?
Ruby mod?
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Re: new build 36lite with vvr
Thanks josh.
Ringing seems slightly less with strat but still there. More prominent with vvr up full. I'll try it bypassed entirely.
Can you link me to some ground loop information please? Google didn't give me anything very specific.
I'm still thinking it could be my poor ac power, I need to try turning off everything which could be causing dirty power.
Ringing seems slightly less with strat but still there. More prominent with vvr up full. I'll try it bypassed entirely.
Can you link me to some ground loop information please? Google didn't give me anything very specific.
I'm still thinking it could be my poor ac power, I need to try turning off everything which could be causing dirty power.
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Re: new build 36lite with vvr
Oh and the ruby mod is already on. I feel like I'm going a bit mad listening to it but it isn't far from sounding right/ good to my ears, just the ringing and slightly unmusical distortion?
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Re: new build 36lite with vvr
I would remove the VVR from the circuit to rule it out.
I would also make sure your outlet is grounded properly, and that there are no external appliances plugged in on the same circuit, and preferably nothing on that can interfere.
I would also try different tubes.
In the recording, it's hard for me to hear it, it sounds like the guitar. It could obviously be something else though.
There's also the possibility that your lead dress could be causing a parasitic oscillation that would negatively impact the distortion sound and cause weird noise like that, but again, you need to work towards ruling things out. I guess post some updated photos of the build and we can see if anything stands out.
I would also make sure your outlet is grounded properly, and that there are no external appliances plugged in on the same circuit, and preferably nothing on that can interfere.
I would also try different tubes.
In the recording, it's hard for me to hear it, it sounds like the guitar. It could obviously be something else though.
There's also the possibility that your lead dress could be causing a parasitic oscillation that would negatively impact the distortion sound and cause weird noise like that, but again, you need to work towards ruling things out. I guess post some updated photos of the build and we can see if anything stands out.
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