Boost Circuits w/ big Volume !

Started by HOTTUBES, February 10, 2013, 04:28:57 PM

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HOTTUBES

I'm looking to experiment with other boost circuits for larger Volume increases ...

I have built these ... and they work , but i have seen boost circuits in other pedals that boast they have 18 -20 db of pure clean volume boost !
What circuits are capable of this type of performance ?

As i said , i have built these ...

SHO
LPB
AMZ mosfet boost
Landgraff



Can you suggest other's ...
Thanks for any help !





samhay

You will ultimately run out of headroom with any gain stage (booster). You could have about 2x as much gain as your best 9V effect if you ran the same circuit (with any necessary tweaks) with an 18V power supply. If you want to stick with 9V, Merlin B (valvewizard) has a nice trick in his Glassblower booster that will get you about 12V peak-to-peak with a 9V battery: http://www.valvewizard.co.uk/glassblower.html. There are probably other designs that use this or similar tricks.
I'm a refugee of the great dropbox purge of '17.
Project details (schematics, layouts, etc) are slowly being added here: http://samdump.wordpress.com

electrosonic

How about John Hollis's Titan Boost




Andrew.
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R.G.

Quote from: HOTTUBES on February 10, 2013, 04:28:57 PM
I'm looking to experiment with other boost circuits for larger Volume increases ...

I have built these ... and they work , but i have seen boost circuits in other pedals that boast they have 18 -20 db of pure clean volume boost !
What circuits are capable of this type of performance ?
Maybe none of them are.

Do you want more audible volume out of your loudspeakers or more distortion from driving your amp (or another pedal) harder?

If it's more volume in the sense of your speakers putting out more sound, you're stuck with what your amp can do. Any electronic device has limits on how big a signal it can put out. For a guitar amp, the final volume is a compendium of the amplifier's electronic output power into the speaker, the speaker's efficiency in turning electrical watts into air pressure changes, and the quirks of human hearing in hearing certain frequencies better than others and the human mind thinking that certain combinations of frequencies are louder.

It is typical for a tube guitar amp to be able to accept something like a volt of signal peak before you overdrive the input tube. No matter what comes after that, the sound will be distorted. Many "boosters" are really designed to get this to happen. Notice that once the input tube is driven as far as it can be and the volume control set so the power amplifier is putting out all the electrical watts it can, you're done in terms of getting more audible sound pressure level. You can get more distortion, and many people like that. That is the basis of the "master volume" setup in some amps.

But if your amp is already putting out as much electrical power as it can, cramming more input signal into the amp's input makes it more distorted, and does not make the amp put out more sound power.

So - do you want more volume, or more distortion? A booster can provide a hotter signal to your amp. It can make the amp distort more. But it can't make the amp louder.
R.G.

In response to the questions in the forum - PCB Layout for Musical Effects is available from The Book Patch. Search "PCB Layout" and it ought to appear.

HOTTUBES

I was after Volume , not more gain or distortion .

ashcat_lt

Volume change (boost or cut) = gain.  Don't care what you usually mean by gain, or how many other people always confuse the term.  You should stop that right now.  Gain is (only) change in voltage or current or both.  In our circuits voltage usually equates to volume.

Distortion is what happens when you try to apply too much gain to a too big signal.  I'd be willing to bet a Fuzzface could give you 18 or 20db clean gain given a small enough input.

tca

If you are looking for a BOOST try this one using the TL431:



"The future is here, it's just not evenly distributed yet." -- William Gibson

roseblood11

MXR CAE MC-401 Booster with 18V power supply. C7 should be 100µF, not 10µF!


Boss FA-1 (my favourite). I'd recommend to use a 18v supply here as well - and a high quality opamp:

R.G.

Quote from: HOTTUBES on February 10, 2013, 09:57:26 PM
I was after Volume , not more gain or distortion .
If that's the case, you have to get a bigger power amplifier, no matter what else you do. You may be able to upgrade speakers to more efficient ones to get a bit more volume, but that's going to be limited to slightly louder.

The human ear has an odd response. More air pressure loudness is perceived almost logarithmically. Getting output that is subjectively twice as loud needs not two times the amplifier power, but about 10 times the power. So if you have a 15W power amplifier, getting subjectively twice as loud requires about 150W.

Driving a bigger amplifier may need a bigger input signal, but probably not. Bigger power amplifiers tend to have more gain, so that about the same input signal produces full output power. A 10W amplifier may be driven to full output by a 1V peak signal. A 100W amplifier is usually set up so that about the same 1V peak signal drives it to full power as well.
R.G.

In response to the questions in the forum - PCB Layout for Musical Effects is available from The Book Patch. Search "PCB Layout" and it ought to appear.

earthtonesaudio

Using guitar speakers in the typical way is great if your ears are located somewhere near the back of your knees.

To actually hear yourself:
Lay the speaker cab down in front of you, and angle it so it points at where your face will be when you play. 
It will be *too loud*.  Adjust the volume down.

If you want other people to be able to hear you better, get a PA, point it at THEIR ears.

Mark Hammer

The best clean boost that aims for maximum volume is a compressor.

As others here have rightly noted, there are limits to what sort of output level can be created from a 9v power supply, and there are limits to what sort of input signal an amp can receive before it runs out of headroom. So, the ideal strategy is not to retain all the dynamics and amplify the entire signal - quiet and loud parts alike - by the same amount, but to feed an amp with the highest clean signal, that elicits minimal amp clipping, that you can.  And to do that, you need to goose the soft parts a lot, and keep a lid on the loudest parts.

Now, few people would sacrifice all dynamics just to have a loud average level.  So, the trick lies in setting the right amount of dynamic compression, ideally with hard-ish limiting on peaks, and more moderate compression below that.  That will keep you below the clipping point in the pedal and in the amp, but still retain some semblance of dynamics.

The SSM2166-based units do a great job on that.

Quackzed

i like the muffer (without the cap/diodes) ,and its LOUD for a 9v booster.
nothing says forever like a solid block of liquid nails!!!

EATyourGuitar

Quote from: HOTTUBES on February 10, 2013, 09:57:26 PM
I was after GAIN without DISTORTION

*fixed*... ^ I think this is what you were trying to say here. even if you get what you want, your amp will clip in the first gain stage if you have enough gain in the pedal. creation audio labs built a pedal that runs on 48v, has 30Db of really really clean gain but not too many people where buying them compared to the 9v, 24Db version. the 30Db pedal is now discontinued but I noticed people are using them mostly for metal and not clean sounds. that amount of gain is absolutely guaranteed to give you the most insane distortion ever when it hits the first 12ax7 in your amp. :o
WWW.EATYOURGUITAR.COM <---- MY DIY STUFF

HOTTUBES

Thanks for everyone's input !!
Awesome stuff !

nascarbean_97


Karaoke party! I used a 15k resistor in place of the 10k, don't know if that affected anything... But yeah, it'll boost the face off your blackface.

HOTTUBES

Thanks .... i have not seen many of these circuits before !