Sm57+MD421 Mic combo for Amp

JamEZmusic

Active member
Sorry to post another thread, I kinda been out of the game for a long time and trying to get back into it so I found myself back here again. I'm curious of you more experienced here have methods of mik'in up a guitar cab.

My main question is, if using the 57 as the core mic, find a nice spot and everything is good, when it comes to placing the 421 in phase using the amp hiss with headphones to find the point where you are out of phase so you can flip the polarity. So what do you do when that second mic is in great phase but in a really crappy position on the speaker cab, I currently have where it's far too bright and during mixdown I need to have the second mic (421) quite far down in the mix that just seems like a lot of work for nothing, I'll admit when I mute the second mic, it does sound worse though! So would much rather keep it in. Just curious as to how you can phase align the mics while having both mics in great sounding positions on the cab?

Also, is it just me or is recording with less gain than you think you need overrated? It seems that attitude of some is if you need more gain, then just record more guitars, or saturate... I am personally diggin my guitar tones with drive on max, I can get the guitar to growl, which you wouldn't be able to get during mixdown using saturation or tracking more guitars I don't think... I am also scooping very heavily, The guitar just sounds better to me. and I really don't feel like they are losing presence during the mix, infact it's helping immensely for percieved power as I am able to sit my leads down lower letting the heavy rhythms/Snare/Bass take the spotlight a bit... Maybe I have bad tastes, I am almost finished mixing a song using that method I think so will probably post it up for feedback on it I really should start to add more mids...

I wasted a lot of time trying to get good guitar tones by not recording with enough scoop/drive. Maybe I could improve my mixes dramatically if I changed my approach but hopefully you will be able to tell me if my mix sucks or not.

Cheers for reading. I am looking for confirmation with my thought processes also.

James.
 
To align them...all you need to do is make sure their capsules are same distance from the speaker. So one mic can be on the left side of the cone, and the other on the right or above/below...whatever.

AFA finding a good spot on the speaker...it's circular, so you have multiple circular points where you can get the same tone...just move the 421 to a "free" spot on the speaker.
 
I see what you mean, But it just so happens that when I phase align the second mic I am in a sub optimal position for best sound, it seemed like I have to move the mic quite a big distance before I get the phase right. So I was not sure if you'd generally spend a long time placing the mics, even reversing the 1st mics polarity instead allowing you to place the second mic in (hopefully) a better sounding place. I am also unsure if it's good to put the mic off axis or pull it back. Just want to follow the tried and tested method so I don't get caught up on it for too long because time is limited and valuable to me right now.
 
I don't understand how you are positioning the mics...are they both the same distance from the grill...or different distances?

If you are using different distances, you will never be able to correct for all frequency phase differences...that's just how it is...so you find where the two mics blend best to your ears. Also...the far mix is picking up more of the room, so that adds to the differences.

If you are using both mics at same distance from grill...then you shouldn't have any phase issues...and you can move the mics around the speaker cone to find the right tone position, but keeping their distance from the grill the same.

I solve the problem most times by simply using one mic that gives me what I want. If I use two mics, I will use them both at the same distance from the grill.
On the rare occasion when I want one close mic and one far mic...I make that far mic noticeably further away...like a few feet, and just use it as a room mic to add some ambiance and depth...but I don't bother with that approach too often.

Don't let phase differences become an obsession of trying to align everything perfectly. It won't work, and much of what we hear naturally has phase differences because most sounds don't reach out two ears always at the same time, same direction. So IOW...embrace the phase differences. ;)
 
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I am also unsure if it's good to put the mic off axis or pull it back. Just want to follow the tried and tested method so I don't get caught up on it for too long because time is limited and valuable to me right now.
The tried and tested methods are tried and tested for a reason. But I think they obscure a reality that there really is no universal "great" sound. Maybe it's just me, but I've found throughout my homerecording life that experimenting is the key because the sound of any particular element only really has to satisfy me. If no one else likes the sound of my guitar in a particular song but I love it, well, tough. There are tons of songs that I don't like specific instrument sounds on but nonetheless love the songs and even the playing of those instruments I may not like the sounds of.
There isn't a question you've asked thus far that you couldn't actually have answered yourself by just trying out and committing to what you liked. Which is not getting at you in any way, more a case of trying to encourage you to like what you like, regardless of whatever a consensus may be.

is it just me or is recording with less gain than you think you need overrated?
Well.....yes, in a sense, it is overrated. Fact is, it's not in every single situation that less gain is warranted. Sometimes, as you've highlighted, much gain is the sound you like and want and fits your song. So it's overrated as a standard practice for every scenario, but when it's right, it's exactly right and perfect and not at all overrated.
 
Just an observation about phase across a speaker cone. Guitar speaker cones are far from pistonic! They react more like a drum head where different parts are moving one way, others another and yet others not moving at all at various frequencies ( we have all seen the 'bowed plate' with fine sand on it and the patterns it produces)

The upshot of this is that one part of a cone can easily be 180dgrs out pf phase with another. As with all things to do with capturing guitar cabs it seems 'cut and try' is the main way?

Dave.
 
Just an observation about phase across a speaker cone. Guitar speaker cones are far from pistonic! They react more like a drum head where different parts are moving one way, others another and yet others not moving at all at various frequencies ( we have all seen the 'bowed plate' with fine sand on it and the patterns it produces)

The upshot of this is that one part of a cone can easily be 180dgrs out pf phase with another. As with all things to do with capturing guitar cabs it seems 'cut and try' is the main way?

Dave.

I get what you mean about a cone vibrating in drum-like fashion...but the idea that one side of speaker can be 180 degrees out of phase with the other, is something I've never heard anyone mention before...and speaker phase issues have been discussed to death.
I think you're just introducing an ambiguous perspective that isn't really relevant in the greater speaker phase discussion, and it will only confuse things.
For most discussions...the whole speaker cone is moving in one direction or another...not some parts of it one way and some the other.
I'm just saying that's the simple, valid way to look at it.

Now AFA some tone difference from say...the left side VS the right side in the same relative spot...I think that might be more to do with the speaker's construction irregularity and/or the cabinet...but generally speaking, I've found that if I put the mic on the left or right or top or bottom in the same relative spot and distance...most speakers will have pretty much the same tone.
 
Some people just tape the 2 mics together and use one clip.

Just recently I picked up a pair of Royer ribbons...and decided to get one of their AxeMount dual mic clips, since I also have SM57 mics, and they apparently combine very well with the Royer 121 mics...so they made the dual clip to hold a 121 and 57.
Mine are actually the 122 active ribbon mics...but they are the same size as the 121, so their AxeMount clip works for any of them that have that same size/shape.

It might even work for some other mics...but there's not too many that have that uniform cylindrical shape like the Royer mics.

As soon as I get done with the studio construction project, I will be trying out that dual mic setup on some guitar cabs. Who knows, it might become my new staple, but I still like using the one mic approach...it just keeps things simple, without additional considerations like phase and alignment.
 
I'm going to guess that a 421 wouldn't fit in that dual clip. That might actually be a good reason to tape it to a 57. That mic clip on the 421 is like Ikea or something, except they don't stock replacements for when they break. Read something a while ago about taking a regular plastic mic clip and cutting the sides off, then carving what you have left so you can slide it in the channel of the 421. If you taper it a little you can get it to jam in there and sort of lock.
 
I get what you mean about a cone vibrating in drum-like fashion...but the idea that one side of speaker can be 180 degrees out of phase with the other, is something I've never heard anyone mention before...and speaker phase issues have been discussed to death.
I think you're just introducing an ambiguous perspective that isn't really relevant in the greater speaker phase discussion, and it will only confuse things.
For most discussions...the whole speaker cone is moving in one direction or another...not some parts of it one way and some the other.
I'm just saying that's the simple, valid way to look at it.

Now AFA some tone difference from say...the left side VS the right side in the same relative spot...I think that might be more to do with the speaker's construction irregularity and/or the cabinet...but generally speaking, I've found that if I put the mic on the left or right or top or bottom in the same relative spot and distance...most speakers will have pretty much the same tone.

I am suitably admonished Miroslav. My feeble contribution was to perhaps reinforce the fact that getting a good sound when micing a cab can be tricky, a fact demonstrated perhaps by your statement that the subject has been "done to death" in this and many other forums.

I'll get me coat....

Dave.
 
I liked this explanation. Which I borrowed.....

Loudspeaker Doppler distortion: the cause
Doppler effect can give rise to distortion - Doppler distortion in moving coil loudspeakers. The distortion is noticed when a high frequency tone is being reproduced at the same time as the cone is moving in and out to accommodate a low frequency tone.The Doppler effect causes the pitch of the high tone increases as the cone moves forwards with the bass tone, and then falls as the cone moves towards the back.

The level of modulation of the high pitched tone is proportional to the amplitude of the low frequency tone. This generates a form of frequency modulation.

It is found that loudspeakers with smaller cones are more affected by the Doppler effect. The reason for this is that they need larger excursions to produce the same audio output. In fact the FM distortion due to the Doppler effect is proportional to the square of the decrease in cone diameter. It is also found to be at its maximum along the axis of the loudspeaker, falling either side.

So...in relation to this question...It's probably not the effect of phase you are hearing with a two-mic setup (I'm assuming the single speaker) but thespread of the capsules resulting in capturing the Doppler distortion....which is sorta the definition of phase anomaly. It will certainly sound very similar.

I use two mics on amps...generally....but I time align the caps and use two very different mics. I have ancient SM57's (1969) and a Royer R-101 which I cannot recommend enough for guitar amps in general. I like a pre that is kind 'Neve-ish' and API EQs.
 
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The science behind this seems to be way beyond the scope of my understanding.

I am mikin the cab with dual mic's as close as i can get them, no axis. Touching grill. I know some people say to leave a gap but I am following Cameron Webbs advice and he uses same mic combination and his results are spectacular. He's produced a lot of my favourite records. (quote:"Cameron Webb" = if there was no grill I would put the mics even closer) I'll note i've never had to use an EQ, or multiband to reduce thumpy boomyness. Maybe my opinion will change when I start recording more heavier palm mutes. I really don't know! (still learning)

Getting the phase right is honestly incredibly easy using headphones and amp hiss, it takes me all of 5 seconds, no exaggeration. Much quicker to phase align the mics than to find the correct tone for the mix. As it happens the tone I got is really complimenting my mix after just a 5khz cut at around 3db(on guitar bus not individual mics). The second mic although bright acts as the ultimate EQ and I definitely need it to compliment the SM57. I would go as far to say that I am getting some of the best tones i've ever recorded recently by using max gain/max scooped sound using amp EQ controls, and EQpedal in loop. Which surprises me as it goes against everything I ever read about online. Maybe partly because I am using a metal amp that is tuned for this type of tone may be helping. I don't know!

What Cavedog & ecc said makes perfect sense to me. The phase relationship I am getting is perfect. I record a quick part and zoom into the waveforms and they look to be identical after the polarity inverse. It really is no effort at all I feel and I will probably from now on use a dual mic setup every time, wether or not I choose to use the second mic in the mix I will leave up to my choice at the end of the day. But it's a backup. much like recording DI. imo.

So not many people here bother phase aligning dual mics by the look of it? I use 1 mic for my lead tone, but really unhappy with the results, still have to figure out how to get great lead tones, but I feel like I have nailed the heavy rhythms so far. I at least know how to place the mics very quickly for my next labour of love.

Taping 2 mics together sounds like a solid approach though! When my Md421 clip breaks, I will probably resort to this ha ha.

Cheers everyone for your thoughts.

Edit: I know I could have figured out a lot of this for myself with lots of trial and error. oh how i've tried so much in the past and failed many times. I am sick of failing, I just wanted to hear how others do their tried and tested method, I feel like recording out of phase might sound better in some instances but for the maximum power of guitars I feel lke recording say 90degrees out of phase could actually be very risky. I can see myself starting to notice artifacts when I am someway into the mix leaving me no choice but to mute a mic, or reamp, or phase align anyway. I am just trying to find ways to speed up the process and thought i'd reach out for help.

Just to clarify though, sm57 pretty central to first speaker, and md421 about 8-10inches (from memory) to the right, so more over the second speaker on a 2x12. Touching grill, no axis, same pre-amp gain so mics peak together. md421 phase flipped. I got the position of the 57 (core mic) while listening through phones and getting tone while listening to the mix in context, the 421 I just phase aligned and didn't care for where it was placed (which is the whole point of me posting this thread up)

Edit again: I will be purchasing a cheap 100£ ribbon mic soon. I hear it's great for it's price but later on down the line I will no doubt purchase the royer121, or royer10. But could be a while away before I can justify the cost. Not to mention the tones I will be recording most are the up front dry 0 room tone kind of recordings, so I really would hate to be very dissapointed with the mic picking up room as it's figure 8 destroying the kind of tones I am going for, I feel like the main use for the mics would then become acoustic guitar recordings, which I think I desperately need a ribbon because my acoustic steel strings are bright as helll..... but again..... cost, had the r121 in wishlist for years and never does seem to drop in price on black fridays or whatever.
 
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The gist is one mic gives what the other lacks.
Blend like salt and pepper.
Ask ten engineers and you get ten different answers.
Many ways to skin a catfish.

G
 
Agree!

My sm57 sounds a little honky/nasal by itself. But not every engineer has my guitar/amp. I personally feel like I have hit the holy grail using dual mic with this combination and tracking/mixing is becoming fun for me again.
 
Agree!

My sm57 sounds a little honky/nasal by itself. But not every engineer has my guitar/amp. I personally feel like I have hit the holy grail using dual mic with this combination and tracking/mixing is becoming fun for me again.

Sub in a SM58.
Keep up the good work.

G
 
I'm going to guess that a 421 wouldn't fit in that dual clip. That might actually be a good reason to tape it to a 57. That mic clip on the 421 is like Ikea or something, except they don't stock replacements for when they break. Read something a while ago about taking a regular plastic mic clip and cutting the sides off, then carving what you have left so you can slide it in the channel of the 421. If you taper it a little you can get it to jam in there and sort of lock.

That's a solid solution for 421 mounting. I did two that way.
Just trim the donor clip such that it slides in easily, because forcing it even a little can cause a body crack/split easily enough.
Drop of hot glue, slide her on it...Never coming out again.
 
...the 421 I just phase aligned and didn't care for where it was placed (which is the whole point of me posting this thread up).

Then maybe I misunderstood your OP, because it sounded to me like you were saying that after phase aligning the second mic...you couldn't find the tone position you liked...or when you found the tone position you liked, then the mic was no longer phase aligned...??

That's why I asked if the two mics were equidistant from the grill or if one was further back...because I couldn't understand the problem you were having of both phase aligning and getting good tone from the two mics. Now it sounds like you're really talking about 2 different speakers and where you "didn't care for where it (421) was placed"...??


Anyway...as long as you get what you want in the end...:)...but I personally wouldn't combine a 57 with 421, as they are too alike in some ways.
With either of those, I would pair with a ribbon most likely if using dual mics...but then, I'm one of those people who never like a 57 on cabs, though like I mentioned, now that I have a Royer 122, I will try pairing the two, since everyone says that is very common pairing in most studio sessions.

My preferred dynamic to a 57 has been the AGD D1000E...it removes both the unwanted and the missing stuff of a 57 (which is why so many people need to pair something with a 57)...so that's how I ended up using a single mic most of the time. Prior to that I was trying some of the Cascade ribbons alone, like the Fat Head and a couple of others...and while they were good alone, I still needed to trim up the low end and sometimes add some clarity in the high end. The AKG D1000E kinda eliminated that....but I never want to get stuck using the same setup over and over unless I wanted the exact same sound over and over.

Your desire to have a quick solution available without any need for experimentation is understandable...but I always enjoyed trying some different setup with each session, and only going with a known solution if I couldn't find what I wanted. There seems to be some kind of time constraint for many guys doing the home/project thing, not sure why...and a need for quick, repeatable solutions, where I tend to lean in favor of experimentation during tracking, and taking the time to find new things, but I'm not on any time constraint.
 
That's a solid solution for 421 mounting. I did two that way.
Just trim the donor clip such that it slides in easily, because forcing it even a little can cause a body crack/split easily enough.
Drop of hot glue, slide her on it...Never coming out again.

I'll keep that in mind. :cool:

When I acquired some 421 mics...just because I felt I needed to add some to my locker...:D...the thing I thought about was the clip issue with them.
It's not even just the problem of breakage...but that when you are attaching them to a stand, it's so easy to press the button and watch the mic fall out...THUMP.
I think that's why so many used ones come with bashed grills...that and the wild drummers who can't aim! ;)

My Senn 441 mics have a similar issue...clips that are very proprietary, and can break easily, especially the clear plastic ones. I also have one with an all-black plastic clip, and that one seems like it's stronger. With them, you "can" sometimes work them into a generic rubbery mic clip...but their square body doesn't usually go into many other clips easily.
 
I am suitably admonished Miroslav. My feeble contribution was to perhaps reinforce the fact that getting a good sound when micing a cab can be tricky, a fact demonstrated perhaps by your statement that the subject has been "done to death" in this and many other forums.

I'll get me coat....

Dave.

You don't have to get your coat. :D

I do get what you were saying about the speaker movement...I just don't think those types of "phase" considerations would be easy to incorporate into hands-on mic alignment for guitar cabs...so for typical daily setups, it's best to just go with the basic ideas of speaker movement. :)
 
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