How to dampen an amp's volume for recording?

Question

Unfortunately I live in a block of flats and strangely enough not everyone appreciates loud guitar music..

However, I'm of the opinion that recording an amp with a mic will pretty much always sound better than a software amp (although I have to admit, Revalver is really good, so I have tried to get the best tone possible).

Does anyone have any tips or tricks to try and restrict the volume of the amp while still getting enough signal for the mics? Specifically, more the bleed into the other flats rather than the volume of the amp itself. The amp is a Bugera TriRec (with adjustable power output) set down to 1W, going through a Marshall 1960AV (however I'm only using the left side to try and keep some volume down so it's actually only coming out of 2 speakers).

I've tried the technique of covering the amp with a thick sheet and it's a good start, but I was wondering if anyone else knew anything I could try?

As a side note, I know it's not an ideal situation and I know the best tones are achieved by getting the speakers in the cab to actually start moving some air, but for demos in a flat, I'm having to make do for now!

Answer 1

Having been down this road myself, I agree that even a quiet amp miked up in a room is much much better than the best amp simulator software I've ever used. And you can get very good tone in an apartment at reasonable levels. The other answers are solid, and I want to add a few things I've learned and used over the years.

Some ways to reduce the sound pressure level coming from your speakers, including ways mentioned by other answers:

• Reduce the output power (you've already done this)
• Reduce the output impedance (look for a 4/8/16 Ohm switch if you have one, set it to the lowest number it has)
• Increase the load impedance of the speaker cabinet (you might be able to do this by actually using all four drivers instead of just two - depending on the wiring of your cabinet)
• Use a less sensitive cabinet or change the drivers in your cabinet to less sensitive drivers (as mentioned by another answer)
• Reduce the bass frequencies in your tone as much as you can stand - they are more likely to annoy the neighbors and you can fill them out again using DIed bass guitar and/or keyboards - or you can DI the guitar before it goes to the amp and get your low end from the DI track, which you can run through an amp simulator or not (I just thought of this idea and I really like it - I'll have to try it next time I record in my apartment!)

Some ways to reduce the amount of sound that makes it into your neighbor's dwellings:

• Get the speaker cabinet up off the floor, ideally on some foam pads or platform designed to isolate the cab from the floor (Auralex makes these, among others)
• Point the cabinet towards a window or exterior wall; if open-backed, stack up pillows or baffles behind the cabinet since open-backed cabinets are almost as loud from the back as from the front - if you point it towards a window put some pillows or drapes in front of the window because reflections off a window will sound really bad getting into the mic
• Build a pillow fort or other baffle system around the amp with the mic inside it (as others have mentioned) Note: This should be a last resort, because whatever baffling you do around the mic and cabinet will at least in some ways reflect sound back to the mic, which will add a lot of early reflections which will sound bad. Also you will be blocking out a lot of the "air" and room tone which is part of the advantage of miking a cab instead of using a speaker simulator or amp modeller. Frankly, if this were my only option I would just DI and use amp modelling instead.

Some other tips:

• Obviously, recording during the day on a weekend is least likely to offend. Late Sunday morning might be best if you are surrounded by church-goers, partly because of the next point:
• With a really quiet amp, you have to make everything else as quiet as possible to have a good signal to noise ratio. Pre-cool or pre-heat the space with the A/C or heater on full and then shut it completely off before you make a take. Do the same with the refrigerator (don't forget to turn it back on!) Finding a daytime period where you're less likely to wake people and trucks are less likely to drive by outside and people won't be coming and going slamming their doors is also important. Around me, Sunday morning is magic time for this. If you live near adherents to some other major religions, you might find Friday or Saturday evening works better.
• Along with the last point, you want to stand as far away from the microphone as possible when recording. If you can get far enough away that you have to wear headphones to hear the amp clearly that's a good sign. If the microphone picks up the acoustic sound of your playing, it's going to sound really bad. It's all pick noise and jangle. You never notice it playing with a loud amp, but if it gets all in the microphone you almost certainly won't like it.
• Try having a friend play and walk around in the lobby of your building to see how loud it is from outside the apartment. Usually more sound gets through the door than the shared walls, so this is often a check of the worst-case scenario. If you feel like it's quiet enough outside the door of your place, then you are probably good.
• The final fail-safe is to DI all of your tracks, get great takes and/or edit them so they are just how you want, and then rent a space for a day and re-amp them all. I would take a DI of every take just as a safety anyway. There are so many uses for a DI copy of a solid take that you're likely to kick yourself if you don't have one.

Edit for one more note/idea:

You can get real tube amp tone silently by sacrificing the speaker and room sound quality. If I have to be 100% silent, I go with a speaker simulator and load box and I take the speaker out from my amp, run it through the simulator and then into the load box. Unfortunately the one speaker simulator that I like (The DMC Cab-Tone) has been out of production for a while. I have a Palmer and a Red Box, both still in production, and I like the Red Box better between those two. Any load that can be a 100% load (instead of just an attenuator) will work, and I find the THD Hot Plate products are solid. This method lets you use all the tone controls, distortion, presence and reverb controls, power tube and output transformer saturation, and all that from your amp without making a lot of noise. It's a bit of an investment though, and still doesn't sound quite as good as a solid mic in a decent room. If you have a great convolution reverb plug-in to add to this very dry tone, it can sound very convincing and totally will blow away any amp simulator.

Answer 2

Given the situation you described I wouldn't go for a miked amp, because you can't really crank the amp, you might have interference from other flats or from the street, etc.

For recording a demo, a good amp simulation will very likely be good enough. But if you really don't want to use software simulation, there's yet another option: use a DI box with speaker simulation, like Hughes & Kettner's Redbox. Note that you will also need a power soak between your amp and the cab simulation / DI box, otherwise you might destroy the power amp if you run it without a load (speaker). This method will give you the amp's sound, except for the speaker, but these days most hardware cab sims are quite good.

Answer 3

If you have some good DIY skills I can't see why you couldn't construct an amp & mic chamber. It would need a way to isolate contact propagated vibrations from the ground such as springs. You would also need to select damping material that was suited for the highest peaks in the audio output (look at the EQ output you see with your mic)

But, unless you have a very good amp and the sound cranked you will probably be better off with software not a real amp.

Answer 4

You need a lower efficiency speaker. It's the only way to significantly change the output of your amp. Speakers are rated with SPL, they average about 98SPL, loudest are the JBL f120s at about 103 SPL.

Every 3db of SPL will double or halve the apparent wattage of your amp. Low SPL speakers are also way cheaper than loud speakers. You can probably get a decent light magnet 90spl 25 watt speaker for about 30 bucks. Scavenge an old practice amp for a cab, close the back up, cover any unused speaker holes with wood and put some fiberglass insulation on the inside back, left and bottom only.

You can't have speakers just hanging out unused. You will need to make a custom ghetto cab. 1x12 in a 2x12 cab will sound huge. Then build a couch "pillow fort" around the cab which should be close miced straight on the grill. Move the mic towards the edge for a brighter sound, towards the dustcap for a darker sound.

And have your parts rehearsed. People will complain about crappy loud music 1000x faster than something that sounds good.

re: Todd's expansion of my answer

I'm glad my pillow fort technique is gaining some traction, but I'm going to disagree on some details here.

First, you should not mismatch output and speaker impedance. It always sounds weak and there is a danger of flyback voltages damaging the amp using a lower z transformer tap into a higher z speaker load.

Second, you must use a closed back cab, close miced. My conception of b the pillow fort is specifically designed to provide an acoustically dead environment to avoid small room ambiance, which simply isn't epic. The fiberglass treatment will break internal standing waves and make the cab sound bigger.

I'd avoid giving the neighbors warning or taking test runs, have your parts rehearsed and nail them. Then shut the operation down until you have more parts down cold.

Answer 5

In a situation such as this (home recording with "unenthusiastic" neighbors) there are two approaches, usually taken together.

1. Build an isolation enclosure. This can be an existing closet space that you retrofit, or a purpose-built "box" that the amp lives within. To be effective, it has to be airtight, and ideally has a frame (including floor and ceiling) that is isolated from the main structure.

   2. Use a "power soak" or "dummy load" on your amp output in series with your speaker. A dummy load is a essentially a resistor that is rated for the output voltage of your amp, and to the amp it "looks like" a speaker impedance. The amplifier thus continues to operate in the same voltage output range as you would use normally, but the majority of the power is dissipated as heat by the dummy load, rather than as SPL from the speaker.