How to fix the volume issue on a Fender Hot Rod Deluxe

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guitarguy101

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I have a 45w Fender Hot Rod Deluxe tube amp, and I noticed that going from 1-4 increases your volume more than going from 4-12. Is there any mod I can do that will solve this issue and give me even volume across the board?
 
probably, but that's just kinda what tube amps do. most of the volume is in the first couple numbers or first 30 degrees of turn.

you could probably put in a different pot (knob which is basically a variable resistor). but i'd just learn to live with it.
 
There is a fix for that. I fixed it on my hot rod deville amp.
The fix is to change out the volume pot. I'm not well versed in electronic tecjnical jargon so with that being said...fender used the kind of pot. that gives you that big volume spike on purpose. When someone checks oit the amp in a music store they say "wow!! If it is this loud on just 3 it will make your ear drums bleed on 8". The truth is that...like you said...you get most of the volume befre the knob even reaches 5. It's a maketing ploy that unfortunately has to be fixed to have an easy controlable volume.
The good news is that any old normal guitar volume pot will work and fix the volume problem. The bad news is that tue volume pot is soldered to a circut board and the stock fender pots have prongs that solder into the board.
I have fixed 2 of these amps. On mine I used a volume pot out of an old bass guitar....I just used 2short pieces of wire qnd soldered them in the circut board where the factory volume pot prongs were soldered. On the second one I just got a stock hot rod deville tone pot and replaced the volume pot with it. That worked like a charm and had the correct prongs that soldered right to the circut board.
 
The fix isn't complicated but let me offer a word of caution in 2 areas.
First is on going into a tube amp to work on it....if your not well versed on doing that. You need to make sure it os unplugged and then you need to get a long rubber handled screwdriver and ground the capacitors to the frame of the amp. I have never persoanally got any kind of spark doing this but the possibility is there for them to hold a potentially leathel charge even after a tube amp is unplugged. Better safe than sorry.

The other area of caution is the desoldering and handling of the circut board. These circut boards are kind of fragile and tend to crack if handled roughly. Also, the contact points in the holes where the prongs go are as fragile as tin foil...if you rupture it you have basically ruined that contact point. you can solder to another contact point but it's easier to be careful and not screw the contact point up.

Just be sure to use desoldering braid and work slowly and be paitiant...don't try to yank the old pot out as soon as you melt the solder. Absord the solder with the braid as it melts and pretty soon the pot will be loose and the contaxt point foil will not be ruptured.
If you use a guitar volume pot and wire it in to the circut board make sure the wire diameter is small enough so that it dosen't rupture the contact point foil.
You may be an ace at soldering to circut boards for all I know but if not....this advise will help you do a successful job
 
You should check the "Ask Eddie" column in the February and March issues of Mix magazine.
Eddie Ciletti does a 2-part article on nothing but the Hot Rod Deluxe and mods you can do to improve it.
 
This problem is as old as Fender, but there are workarounds. It's the taper of the potentiometer, so trying different pot resistance values, or trying a linear instead of a log taper, or a different brand, or whatever it takes to make you as happy as possible is the only answer. Right now the pot is 250K audio taper. If you talk nicely to your Fender service center repair guy, you can buy whatever pot you need for about $6 up here in Canada, so it can't be that expensive no matter where you live. My service guy also does Marshall, or Peavey, so there are other brands of pots to try. Try 100K, try 500K, try linear taper, try a Peavey pot. The 'best' solution is a reverse audio taper pot, but finding one in a value you like, and that will mount to the Fender circuit board, is kinda like trying to nail Jell-O to a tree. Do the best you can with what you have to work with.
 
ranjam said:
This problem is as old as Fender, but there are workarounds. It's the taper of the potentiometer, so trying different pot resistance values, or trying a linear instead of a log taper, or a different brand, or whatever it takes to make you as happy as possible is the only answer. Right now the pot is 250K audio taper. If you talk nicely to your Fender service center repair guy, you can buy whatever pot you need for about $6 up here in Canada, so it can't be that expensive no matter where you live. My service guy also does Marshall, or Peavey, so there are other brands of pots to try. Try 100K, try 500K, try linear taper, try a Peavey pot. The 'best' solution is a reverse audio taper pot, but finding one in a value you like, and that will mount to the Fender circuit board, is kinda like trying to nail Jell-O to a tree. Do the best you can with what you have to work with.
Click to expand...
It's a linear pot now...replacing it with an audio is the fix.
That's why a tone pot for the same amp fixes the problem and fits the circut board.

The linear pot is what gives the amp the volume spike. Most any value audio pot will give alot smoother volume control.
The tone pot works very well amd it's easy to ask for without getting into alot of technical jargon like "audio pot" "linear pot" and specific values. You can keep it simple and just say "I want a tone pot for a hot rod deluxe amp".
My 2 cents
 
Every tube amp I've ever owned has had this same characteristic. I just leave it alone and use it. I don't see why it's a problem.

Also, I understand audio vs linear pot. So if the solution is that simple and there's no drawback, why don't amps come with audio pots in the volume to begin with? they cost the same amount and they are the exact same thing to instal? I figure why mess with 60 years of tube amp tradition.
 
aaronmcoleman said:
Every tube amp I've ever owned has had this same characteristic. I just leave it alone and use it. I don't see why it's a problem.

Also, I understand audio vs linear pot. So if the solution is that simple and there's no drawback, why don't amps come with audio pots in the volume to begin with? they cost the same amount and they are the exact same thing to instal? I figure why mess with 60 years of tube amp tradition.
Click to expand...
All tubes amps have linear volume pots??
I don't think so....are you sure about that?
The reason they put the linear pot in there is to make the volume spike when you barely turn the knob...it gives the prospective buyer the illusion that the amp is 3 times more powerful than it actually is. Then when the prosective buyer tries the next amp out and the volume is much lower at the same position they think it lacks the power of the HRD.
At least thats a theory and opinion.
The fix IS that simple....I know because I have already fixed a couple of them.
As far as all tube amps having this characteristic....you need to try out a deville amp because it's in a league of it's own in terms of the volume pot problem.
Belueve me, I would NEVER have gone through the total pain in the ass of dissasembling, desoldering a pot from a circut board, and putting it all back together over volume control being the same as every other tube amp out there
 
jimistone said:
All tubes amps have linear volume pots??
I don't think so....are you sure about that?
The reason they put the linear pot in there is to make the volume spike when you barely turn the knob...it gives the prospective buyer the illusion that the amp is 3 times more powerful than it actually is. Then when the prosective buyer tries the next amp out and the volume is much lower at the same position they think it lacks the power of the HRD.
At least thats a theory and opinion.
The fix IS that simple....I know because I have already fixed a couple of them.
As far as all tube amps having this characteristic....you need to try out a deville amp because it's in a league of it's own in terms of the volume pot problem.
Belueve me, I would NEVER have gone through the total pain in the ass of dissasembling, desoldering a pot from a circut board, and putting it all back together over volume control being the same as every other tube amp out there
Click to expand...

I'm not doubting you. I was actually genuinly curious if there was a legit reason.

I have a few amps (twin, HRD (1x12), Dr. Z, Orange) and they all spike in the first few degrees of turn, so I just assumed they all have a linear pot. I don't use the HRD very often anymore, so maybe it's worse than the others at this...I'll have to check.

Sorry, I wasn't trying to cause a problem. So most tube amps have an audio pot?
 
I have a Fender Frontman 25R practice amp that has the exact same thing - they must use it on all their amps... You get all your volume from 1 ~ 3 after that it's negligible.
 
aaronmcoleman said:
I'm not doubting you. I was actually genuinly curious if there was a legit reason.

I have a few amps (twin, HRD (1x12), Dr. Z, Orange) and they all spike in the first few degrees of turn, so I just assumed they all have a linear pot. I don't use the HRD very often anymore, so maybe it's worse than the others at this...I'll have to check.

Sorry, I wasn't trying to cause a problem. So most tube amps have an audio pot?
Click to expand...
It's cool....no problem.
To tell you the truth I have owned only 3 fender amps...an old super reverb, an old twin, and the HRD. The old ones were point to point wiring and had auduo pots I assume. The volume pot was smooth on rhose old ones. I had other tube amps like marshalls, peaveys, messa....never had a volume pot problem. I haven't played through many of the newer circut board amps to tell the truth.

They may all have linear pots for the volume now...I dunno.

I believe it's a marketing thing and that's really a shame because the audio pot is much better and makes the amp volume si much easier to control.
 
I had an old solid state Fender Princeton Chorus and it was the same way. You'd get a big spike in volume within the first few degrees of turning the volume knob, and the rest of the knob's travel made much less of a difference.

The 2 tube amps I have now are both very smooth in their output along the travel of the master volume knob.
 
I believe logarithmic controls were supposed to work with how our ears perceive volume increases.

06-audio-or-linear-taper-pot_d7f334d410.png​

Linear controls are more or less voltage dividers, and you don't see them often in guitar gear. I sometimes use them as tone controls in a guitar, because that's where the 'it's either on or off' phenomenon really bugs the crap out of me. Reverse-log controls work 'backwards' (hence the name), where all the volume seems to be at the end of the control, and is 'better' for me, but they're impossible to find.
 
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