Transformerless mic to record DSL5cr amp with

[PelliX]

If you're setting the amp volume way too low and cranking the interface's input volume that could cause hum. Maybe turn the amp up a bit and lower the gain on the interface.

I certainly agree, but the hum still comes from somewhere. Even if one choses not to address the root cause but work around it for whatever reason - and we all do this sometimes - it's good to know why/what/where/how so that the next time you already have a battleplan in your head.

Try to do a ground lift on the mixer or at least on the channel the mic is plugged in. An isolation transformer between the amp and mixer could possibly help too.

Ground lift is going to be tricky if he's running the Cloudlifter in the chain which requires phantom power. I'd leave the CL out of the equation for now. As @ElvisNixon outlined; simplify the setup, run through each bit. As the amp and mixer are not coupled, this should not be an issue. The DSL's aren't typically an issue for other gear on the same circuit. If the mixer's power supply was acting up, one would expect to notice that on its outputs *generally*. What kind of mixer is this?

 

[guitarbilly74]

I certainly agree, but the hum still comes from somewhere. Even if one choses not to address the root cause but work around it for whatever reason - and we all do this sometimes - it's good to know why/what/where/how so that the next time you already have a battleplan in your head.



Ground lift is going to be tricky if he's running the Cloudlifter in the chain which requires phantom power. I'd leave the CL out of the equation for now. As @ElvisNixon outlined; simplify the setup, run through each bit. As the amp and mixer are not coupled, this should not be an issue. The DSL's aren't typically an issue for other gear on the same circuit. If the mixer's power supply was acting up, one would expect to notice that on its outputs *generally*. What kind of mixer is this?

Yeah, I wouldn't use a Cloudlifter with a 57. I don't think it's necessary at all. The 57 definitely has enough output for a guitar amp, especially into modern interfaces.

 

[ElvisNixon]

I didn’t realize that you have such a complex and somewhat convoluted system. There’s a myriad of things that can be causing the noise problems.

I would recommend that you re-think what you’re trying to accomplish and simplify as much as possible. Even in big professional studios there are problems that arise when they make changes or a client with a large complex system of there own comes in. There are a few “noise doctors” who make big money by fixing noise problems for the big studios who don’t have the option to simplify and streamline their studios.

In light of what you’ve described, it’s got to be a ground loop issue. I’ve seen situations where it turned out to be the individual pieces of outboard equipment mounted in an equipment rack making a ground loop by contacting metal to metal with no washers.

The solution was to use two plastic washers to mount the gear in the rack. One washer between the rack itself and the gear mounted in it and the other on the normal front of the gear position to isolate the rack screws from the front of the equipment.

You really would be well served by keeping everything as simple as possible to do the job.

You really need to tell us everything you have and how it’s hooked up and what you’re trying to accomplish for us to do more than make educated guesses.

like 57>Focusirite>mixerXLR>____ etc. Tell us how it’s connected and with what cables.

Ground lifts are something best used in emergencies like a live performance. Best case is they are a band aid and worst case you could be electrocuted. I’ve been in studios where touching a rack and the mixing console at the same time would give you a shock. Don’t lift grounds for a permanent solution. Just my .02 and YMMV.

 

[Emenius Sleepus]

Should do, yes. Check if the switch makes any difference - it shouldn't.



There's something wrong there, and I'd almost say it smells a bit like cables somehow. A 57 with a Cloudlifter through an 8i6 mic preamp should result in a pretty hot signal. The Cloudlifter will isolate the downstream mic from any phantom power, but if you're plugging the mic straight in, best to keep it off. It won't hurt the 57 (neither will a car rolling over it or a medium sized nuclear explosion), but it can cause odd issues.

Here's an idea, does the mixer have mic inputs? Have you tried plugging a 57 into that and checking if you get any hum? If not, then run the main/master/monitor/channel/whatever outputs to the interface and record some. Any hum in the recording? Note that you should of course use the jack inputs at Line level for that on the Scarlett.

Yeah when I get my 5 watt amp back I'll test it.

Yeah the Cloudlifter was only used with the 8i6, when I used the mixer (Yamaha MG10) it has better pre amps so a CL-1 was never needed. But I still had the hum.

Yes the mixer has mic inputs and that's what I was using for our live video. I will admit I'm using xlr - xlr from the MG10 mixer to the Scarlett. I should probably be using XLR - TS or TRS.

 

[Emenius Sleepus]

Yeah it could be just gain staging too. If you're setting the amp volume way too low and cranking the interface's input volume that could cause hum. Maybe turn the amp up a bit and lower the gain on the interface. You can throw a blanket on top of the amp and mic if you need a bit less volume in the room, have the amp facing a different direction or even set the amp up in a different room.


This could indicate a ground loop between the amp and mixer and possibly even the interface. Try to do a ground lift on the mixer or at least on the channel the mic is plugged in. An isolation transformer between the amp and mixer could possibly help too.

May well be, the amp is never turned up more than 1/4 way. I thought about building an iso cab box thing for the amp to sit in when recording and then I can turn it up even louder. Or, like you suggest face it away from us or in another room.

A ground loop between the amp and mixer is a possibility as its more loud when I use that, and the Cloudlifter.

 

[Emenius Sleepus]

I didn’t realize that you have such a complex and somewhat convoluted system. There’s a myriad of things that can be causing the noise problems.

I would recommend that you re-think what you’re trying to accomplish and simplify as much as possible. Even in big professional studios there are problems that arise when they make changes or a client with a large complex system of there own comes in. There are a few “noise doctors” who make big money by fixing noise problems for the big studios who don’t have the option to simplify and streamline their studios.

In light of what you’ve described, it’s got to be a ground loop issue. I’ve seen situations where it turned out to be the individual pieces of outboard equipment mounted in an equipment rack making a ground loop by contacting metal to metal with no washers.

The solution was to use two plastic washers to mount the gear in the rack. One washer between the rack itself and the gear mounted in it and the other on the normal front of the gear position to isolate the rack screws from the front of the equipment.

You really would be well served by keeping everything as simple as possible to do the job.

You really need to tell us everything you have and how it’s hooked up and what you’re trying to accomplish for us to do more than make educated guesses.

like 57>Focusirite>mixerXLR>____ etc. Tell us how it’s connected and with what cables.

Ground lifts are something best used in emergencies like a live performance. Best case is they are a band aid and worst case you could be electrocuted. I’ve been in studios where touching a rack and the mixing console at the same time would give you a shock. Don’t lift grounds for a permanent solution. Just my .02 and YMMV.

Yes since experiencing the humming I've gradually changed the way I record audio, now its straight into a DAW without a mixer. So Amp - SM57 - (sometimes CL-1) into Focusrite. Before it'd be using 2 hardware devices (i.e mixer into interface as the mixer has no USB out). I do understand this complicated things which is why I'm now recording the audio first.

Once I get my 5 watt amp repaired and back then I will test again with the stock speaker and the Orange 1x12. Right now I can only test with my 1 watt and its not causing any issues so far.

 

[PelliX]

I will admit I'm using xlr - xlr from the MG10 mixer to the Scarlett. I should probably be using XLR - TS or TRS.

Most definitely.

A ground loop between the amp and mixer is a possibility as its more loud when I use that, and the Cloudlifter.

I don't see how the amp would be connected to the mixer? Not only is the microphone not ground referencing the two together, but the CL would isolate it a little more yet. Am I missing something in the setup?

 

[Emenius Sleepus]

Most definitely.



I don't see how the amp would be connected to the mixer? Not only is the microphone not ground referencing the two together, but the CL would isolate it a little more yet. Am I missing something in the setup?

The amp is mic'd up via the 57 xlr - xlr into one of the mic inputs on the mixer. Nothing else.

 

[PelliX]

The amp is mic'd up via the 57 xlr - xlr into one of the mic inputs on the mixer. Nothing else.

Right, that's not causing a ground loop in any case.

 

[JohnH]

Seems like striping the whole rig back to simpler is the way to go then add things back if you need them. So '57 to xlr mic input on the interface, to DAW, no cloudlifter, nothing else. If you just do that, and sing into it (ie no amp or cab nearby), can you get a clear hum-free recording? Then try micing the amp.

I use a Rode M1 dynamic mic, it's a few dB's less sensitive than a '57 or '58 and it's more than enough output even for a speech recording, and plenty for any close-miced amp even though I'm attenuating amps down to much less than a watt.

 

[guitarbilly74]

I will admit I'm using xlr - xlr from the MG10 mixer to the Scarlett. I should probably be using XLR - TS or TRS.

That's an issue. When you go XLR-XLR from the mixer to the Scarlett you are plugging the mixer - which is line level - into the Mic Preamp of the Scarlett.The way the combo jacks on these interfaces work is when you plug an XLR cable it activates the Mic Pres and set the input level to Mic level. When you plug TS or TRS, it bypasses the Mic Pre and you can switch between either Line or Instrument level.

So if you want to use the mixer, you have to use balanced XLR- TRS cables so the Scarlett bypasses the Mic Pre and takes the line level signal from the mixer.

Bu better yet, just take the mixer out of the equation completely and plug the mic straight into the interface.

 

[Emenius Sleepus]

That's an issue. When you go XLR-XLR from the mixer to the Scarlett you are plugging the mixer - which is line level - into the Mic Preamp of the Scarlett.The way the combo jacks on these interfaces work is when you plug an XLR cable it activates the Mic Pres and set the input level to Mic level. When you plug TS or TRS, it bypasses the Mic Pre and you can switch between either Line or Instrument level.

So if you want to use the mixer, you have to use balanced XLR- TRS cables so the Scarlett bypasses the Mic Pre and takes the line level signal from the mixer.

Bu better yet, just take the mixer out of the equation completely and plug the mic straight into the interface.

I don't use this method anymore for recording, but still use it to live stream (online guitar lessons). I have tried xlr to trs and found the signal to be weaker and quieter meaning I've had to use a bit of preamp gain on the interface.

But recording wise yeah mic straight into interface.

 

[Emenius Sleepus]

Ok so got my DSL5 back yesterday, all fixed. If anyone is interested here's a report of what the tech did:

Checked the mains fuse- found it was blown. Replaced the fuse, connected test equipment and applied power.
Found the amp powered on ok.
Connected a dummy load and scope.
Input test signal and checked power output.
Found the output signal was very low and very distorted.
Removed screws and removed the chassis from the cabinet.
Removed valves for testing.
Please see separate report.
Found 2nd preamp valve had a bad triode - replaced with a JJ from stock
Sourced and ordered and replacement 12BH7

It's working and sounding great now so will do further recording tests with my SM57. I now know the location of the transformer on the amp but I think ultimately the Orange cab sounds better anyway which I believe don't have transformers in them?

 

[PelliX]

Checked the mains fuse- found it was blown. Replaced the fuse, connected test equipment and applied power.
Found the amp powered on ok.

Wow, the mains fuse popped, too? Ok...

Connected a dummy load and scope.
Input test signal and checked power output.
Found the output signal was very low and very distorted.
Removed screws and removed the chassis from the cabinet.
Removed valves for testing.
Please see separate report.
Found 2nd preamp valve had a bad triode - replaced with a JJ from stock
Sourced and ordered and replacement 12BH7

We'll skip the separate report, then, hehe. Interesting, though; a knackered preamp valve, a dead output valve *and* a blown mains fuse. Was it the victim of some kind of electrical surge? It's too coincidental for a bit of bad luck.

It's working and sounding great now so will do further recording tests with my SM57. I now know the location of the transformer on the amp but I think ultimately the Orange cab sounds better anyway which I believe don't have transformers in them?

Correct, cabs typically only contain speakers (and a jack), no transformers. If the cab sounds better to you then by all means continue using it.

 

[Emenius Sleepus]

Wow, the mains fuse popped, too? Ok...



We'll skip the separate report, then, hehe. Interesting, though; a knackered preamp valve, a dead output valve *and* a blown mains fuse. Was it the victim of some kind of electrical surge? It's too coincidental for a bit of bad luck.



Correct, cabs typically only contain speakers (and a jack), no transformers. If the cab sounds better to you then by all means continue using it.

Yeah it popped and just turned off randomly during a lesson with someone, then refused to turn back on after which would explain the fuse blowing.

I don't think it was a surge, after all it is 6.5 years so something was going to go on it at some point. Or maybe I was just unlucky.

Hmm....well seeing as I already have all the stuff to use with another cab then for now recording with the Orange is my best bet right now. I don't think they make V30's in 10 inch speaker sizes or do they? Otherwise I'd consider swapping out the stock speaker, though this isn't really a recording amp.

 

[PelliX]

I don't think they make V30's in 10 inch speaker sizes or do they?

Well, sort of:

Celestion G10 Vintage - 10 inch 60W Guitar Speaker

Celestion G10 Vintage - A 10 inch guitar speaker with powerful ceramic magnet and the same voice coil design as the Vintage 30 - packs an impressive punch

celestion.com

Celestion actually has a nice comparison function on their site, you might want to check it out.

I don't think it was a surge, after all it is 6.5 years so something was going to go on it at some point. Or maybe I was just unlucky.

Sure, sooner or later something will give, but three things at once, including the mains fuse. Hmm. Ah well, it's back in business now.

Otherwise I'd consider swapping out the stock speaker, though this isn't really a recording amp.

My experience is that 10" speakers in combos never sound as good as a 12", let alone a 12" in a proper cab. Anything open back or semi-open back will also be harder to mic/record 'the way it sounds in the room', too. My experience, opinion and taste, of course - feel free to ignore.

 

[Emenius Sleepus]

Well, sort of:

Celestion G10 Vintage - 10 inch 60W Guitar Speaker

Celestion G10 Vintage - A 10 inch guitar speaker with powerful ceramic magnet and the same voice coil design as the Vintage 30 - packs an impressive punch

celestion.com

Celestion actually has a nice comparison function on their site, you might want to check it out.



Sure, sooner or later something will give, but three things at once, including the mains fuse. Hmm. Ah well, it's back in business now.



My experience is that 10" speakers in combos never sound as good as a 12", let alone a 12" in a proper cab. Anything open back or semi-open back will also be harder to mic/record 'the way it sounds in the room', too. My experience, opinion and taste, of course - feel free to ignore.

Ah ok, I'll check it out though in reference to your last paragraph you're right - 10 inch speakers probably aren't going to sound as good as a 12 inch one, as I think I'm finding out when I'm A/B'ing my Orange and the stock speaker.
I'll also add the previous way of recording with it was live, and within an hour's guitar lesson so there's little to no time to tweak things and try different settings/positions etc etc. Now I am a bit more experienced and record differently (straight into a DAW) I can appreciate the better way of doing things and have more experience on what doesn't sound as good.

Yeah, I don't think it was a misuse thing (or I certainly hope not) I never cranked it up full or used it for a gig. There've been a few over enthusiastic learners who don't know that switching it on and off repeatedly and fiddling with the dials could have affected it (probably not). I don't really play through it much myself, its more for the learner.

 

[PelliX]

I never cranked it up full or used it for a gig.

It should handle that, too. Of course it will be a little rougher on it, but provided it has a bit of ventilation and it doesn't get rattled to pieces it's fair game. You won't get 20 years of maintenance-free life out of it gigging three times a week but there's no harm in pushing a bit of air from time to time. Personally, I believe that kit sometimes needs to be "exercised" occasionally.

There've been a few over enthusiastic learners who don't know that switching it on and off repeatedly and fiddling with the dials could have affected it (probably not).

Fiddling is fine, but the rapid power on/off/on cycles are harsh. That slams the capacitors, the diodes, the heater filaments in the valves, etc.

Good luck with the recording, lessons, etc!

 

[Emenius Sleepus]

It should handle that, too. Of course it will be a little rougher on it, but provided it has a bit of ventilation and it doesn't get rattled to pieces it's fair game. You won't get 20 years of maintenance-free life out of it gigging three times a week but there's no harm in pushing a bit of air from time to time. Personally, I believe that kit sometimes needs to be "exercised" occasionally.



Fiddling is fine, but the rapid power on/off/on cycles are harsh. That slams the capacitors, the diodes, the heater filaments in the valves, etc.

Good luck with the recording, lessons, etc!

I've never turned it past halfway so that might have to change when recording haha. But I think if I use the 12 inch speaker I will find I won't have to because its a bigger speaker so more air comes out.

Yeah and also not turning it off before unplugging cables. Just inexperience/nerves/lack of respect for my gear haha.

Thanks for all your advice and input though, I've really learnt a few new things in the process and hopefully get a better recorded sound from this (and the 1 watt) amp.

 

[PelliX]

Yeah and also not turning it off before unplugging cables.

No harm in that, as long as it's not the speaker cable (and the amp isn't on standby). Pulling the guitar lead is perfectly fine for the amp. Pulling the power cord is the same as flipping the switch, so no harm there, either. Just sayin'.

Also, just FYI, people have managed to cram a 12" speaker in the 5CR. Personally, I'd just go with a cab, but you would not be the first person to do it.

MARSHALL DSL5CR COMBO AMP with 12” CELESTION GREENBACK - A Guitar And Gear Support Forum