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Putting a choke on an amp?


Assumer

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Well, fryette did take out the choke on the deliverance revision for example and put a resistor in its place. At least, choke mods are cheap in the first place.

 

I remember reading somebody that put a choke on his marshall JVM and was a world of difference. Wouldn't hurt to try.

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A resistor-capacitor filter is simple and inexpensive. When it needs to supply lots of current, however, it creates a large DC voltage drop, requiring a higher input voltage to achieve the same output. In high-power guitar amplifiers the power tube screens, phase inverter, and preamps draw enough current at full power to make a choke-capacitor filter more economical (at least in the early days of the Fender Bassman and the Marshall JTM45).

 

 

 

An LC filter with the same amount of ripple attenuation and the same size capacitor creates much less DC voltage drop than an RC filter. The key difference is that the inductance of the choke reacts to AC signals but presents, ideally, a short circuit to DC. A real-world choke creates only a slight DC voltage drop due to internal winding resistance.

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What does the choke actually do to the sound??

RLC is a better filter than just RC. An RC is really a Voltage filter and an RLC is both Voltage and Current.

 

A well designed amp with a choke will have less sag. The result is a punchier bottom end.

 

The choke stores energy in its magnetic field and delivers this as current... which is needed when delivering bottom end power. Basically a constant current source.

 

A Capacitor stores energy in its electric field and delivers this as voltage. Basically a constant voltage source.

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I put one in one of my DSLs that I had, and I would do it again if I got another DSL. It was easy to do (for me at least), and the change in sound was subtle. But when I turned it up to gigging levels, the choke gave the amp a tighter feel, which I really loved! It lessened the sag that the amp had by some bit, it didn't turn it into a VHT/Fryette tightness, but it did help.

 

Cole

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From what I've read, "a choke would have less? compression since having a resistor as an inductor is what will give you sag. Chokes do not sag."

 

Robbne Ford's Dumble has the resistor instead of a choke in the power supply to get more compression and sag! :lol:

 

 

188621d1286851342-can-someone-show-me-24

 

Flame suit on!

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Most of your sag is due to the power tube anodes pulling a lot or current. The choke would make part of the filter after this stage of the power supply to feed the screens and usually the preamp from there which shouldn't be drawing enough current to pull down the supply voltage and sag.

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I added a choke to my old Yamaha T-100, as recommended by Mike Soldano. The mod was cheap (Mercury Magnetics choke $30, solder and soldering irons already in my kit), easy (it was the first soldering work I'd ever done inside an amp and, homework done in advance, I did it perfectly in 30 minutes), and did make an audible difference, at least at volume. Low-end response was audibly bigger and faster above once you got to "band practice" volume levels. I didn't notice any reduction in hum or noise, but it was a fairly quiet amp to start with.

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I was told that a choke filters out the unwanted noise that a lot of amps produce supposedly letting the more "musical" harmonics/requencies shine through better.

 

My rivera has a choke in it but my peavey does not so that's my only experience with it with massive playing time. Many higher end amps have a choke in them so that could be part of why they're "higher end."

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I was told that a choke filters out the unwanted noise that a lot of amps produce supposedly letting the more "musical" harmonics/requencies shine through better.


My rivera has a choke in it but my peavey does not so that's my only experience with it with massive playing time.
Many higher end amps have a choke in them so that could be part of why they're "higher end."

 

 

Not true. The JVM does not have a choke and it is "high end".

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well like I said "highER" end amps. Obviously there will be some high end amps that use them, and low end amps that do. Here's an explaination from aiken amps

 

"Why use a choke? Why not just a big series resistor?

A choke is used in place of a series resistor because the choke allows better filtering (less residual AC ripple on the supply, which means less hum in the output of the amp) and less voltage drop. An "ideal" inductor would have zero DC resistance. If you just used a larger resistor, you would quickly come to a point where the voltage drop would be too large, and, in addition, the supply "sag" would be too great, because the current difference between full power output and idle can be large, especially in a class AB amplifier."

 

also this

http://www.300guitars.com/articles/chokes-what-are-they-what-do-they-do/

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well like I said "highER" end amps. Obviously there will be some high end amps that use them, and low end amps that do. Here's an explaination from aiken amps


"Why use a choke? Why not just a big series resistor?

A choke is used in place of a series resistor because the choke allows better filtering (less residual AC ripple on the supply, which means less hum in the output of the amp) and less voltage drop. An "ideal" inductor would have zero DC resistance. If you just used a larger resistor, you would quickly come to a point where the voltage drop would be too large, and, in addition, the supply "sag" would be too great, because the current difference between full power output and idle can be large, especially in a class AB amplifier."


also this

http://www.300guitars.com/articles/chokes-what-are-they-what-do-they-do/

 

I understand. My point is, sound is very subjective, and a choke only changes the tone very little anyway.

 

Speakers, tubes, and using an eq can alter your tone much more! :)

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