More headroom in an amp: what does this do?

[Brown Rug]

Does it sound smoother than an amp with a lower wattage? Enlighten this noob.

[NaturalBornBoy]

In very simplistic terms, more headroom means you can push the amp harder before it starts to distort.

[Cirrus]

If you have headroom to spare, when you play the guitar louder the sound coming out the speakers will also get louder. There are lots of points between the guitar and the speaker that can run out of headroom, and at that point they compress and distort. Pickups, pedals, each gain stage in the preamp and power amp, transistors, transformers and speakers will all reach a point at which any extra power going into them can't be passed on down the chain, at that point you've ran out of headroom.

[Brown Rug]

 

If you have headroom to spare, when you play the guitar louder the sound coming out the speakers will also get louder. There are lots of points between the guitar and the speaker that can run out of headroom, and at that point they compress and distort. Pickups, pedals, each gain stage in the preamp and power amp, transistors, transformers and speakers will all reach a point at which any extra power going into them can't be passed on down the chain, at that point you've ran out of headroom.

 

 

Would more or less headroom cause compression?

[newholland]

 

Would more or less headroom cause compression?

 

 

less headroom causes compression.

 

if you think of it this way-- any electronically amplified sound creates a waveform. with LESS headroom-- the tops and bottoms of that wave get squashed off-- THAT is compression. if you have more headroom-- those waves get passed through unmolested.

[chriscnb]

 

Would more or less headroom cause compression?

 

 

Less headroom

[Pepi]

[WRGKMC]

Headroom is just another term used for an amps RMS wattage.

RMS is measured for its maximum level before distortion occurs.

Peak wattage is the maximum output including distorted tones.

 

Neither of these describe how loud an amp is in decibels.

Speaker efficiancy is a key factor that comes after the amp.

A speaker with a high SPL (sound pressure level) can give an

amp more clean headroom than a low SPL speaker for the same wattage

being applied to both.

 

You also have how quickly a speaker can react to transients.

A lightweight cone (which is ofthen a higher spl) will react faster

than a heavy weight cone do to the inirtia of the mass in motion

and its ability to stop, go and change directions quickly.

 

For guitarists, its usually a balance of compression and

dynamic responce. If a speaker is too responsive,

it may be difficult for a guitarist to maintain a steady dymamics

and even a slight difference in strum strength may cause a big jump in

loudness. On the other hand, if the speakers are too heavy/compressed

the guitarists volume may be monotone and he will have a difficult time

following a drummers change in dynamics.

 

I try to match my speakers so an electric has acoustic like dynamics playing clean.

I can always use drive and compressor pedals to limit dynamics if needed.

 

You can also use combinations of speakers for both a tight and loose dynamics

and get all kinds of varieties along the volume curve to suit your playing style.

I often do this when recording two or more amps with different speakers and cabs.

You can have one track thats punchier for chords and one that rips for leads, then

just work out the differences mixing.

[fretless]

makes the chicks dance ?

[zehn]

Really depends on what you mean by "headroom". If you mean clean headroom, it basically means how loud can the amp and speaker (they work interactively, and as mentioned above a speaker with a higher sensitivity rating and wattage rating will stay cleaner louder) get before distortion is added into the sound, whether it be from pedals, the preamp, poweramp, OT, or the speakers and cabinet itself.

 

Obviously there are a lot of factors to consider, and when you add in cascading gain stages, pedal distortion or db boosts into the mix it basically comes down to how loud can you get before turning the volume up on your amp or pedal only adds more gain and compression, and not an actual increase in perceived volume.

 

It's a complicated issue but normally amps with a higher wattage rating will have more headroom than those of a lower rating. 100 watt amps stay clean considerably louder than 30 watt amps and with that headroom comes sensitivity to your pick attack at high volumes, etc.

 

Depending on the amp and speaker(s) you're using and your entire signal chain.

 

Depending.

[Brown Rug]

Gotcha. Thanks guys for the response. The reason why I'm asking is because I'm planning on getting a Thunderverb, but I'm not sure which one would be best for me. I'm not a fan of a compressed sound, so I'm guessing based on what I've read the 200 is right up my alley - despite probably never needing 200 watts haha.

[zehn]

200 watts is a bit scary to me considering I have a vintage JMP and 2 channel Triple in my basement. Sometimes I run them in stereo cranked, which is more than enough volume to shake light fixtures out of the ceiling and knock pictures off the walls. I wonder what a 200 watt Marshal Major pushing 290 at the OT would sound like

 

FWIW wattage rating has nothing to do with the sonic character of the amp or how compressed it will be, these are only guidelines really.