Fender Hot Rods: Why is a Deville 60 watts and a Deluxe only 40watts?

[mrkgtr49]

Looking at the two amp series, why would one be rated at more output than the other? They appear to have the same output stages and the same pre-amps. I don't get it.

Thanks!

[pdf64]

The main things that determine power output are the VB+ (and how 'stiff' it is under load), output transformer primary impedance and the output tubes (what the Va-k is when saturated). The schematics show that the Deville has a B+ of 485V, the Deluxe B+ is 427V, which is probably enough of a step up in itself, without the output transformer primary impedance being different.
Pete

[Enzo]

What Pete said.

They are NOT the same power amps. The 50v B+ difference alone is significant, the two output transformers are not the same.

[Chuck H]

As a side bar... If you stuck a speaker with three dB more efficiency (not hard to find) into the HRDeluxe it would be LOUDER than the HRDeville. The actual volume of either amp, speakers being equal, would be something just under two dB difference. So DO just pick the amp that sounds best to you.

[Enzo]

Which brings us to something I like to point out - power is not loudness.

[Chuck H]

Nope. It's not. There's a lot of buzz about using lower power amps as a means of getting cranked amp tone at different volumes. I use an attenuator. But I do much prefere to run au naturale. But along this line... Lower efficiency speakers have been suggested at times to lower an amps loudness. But as a player I have to say that the more efficient speakers seem to "feel" better to me. Even if the amp is low wattage. I've never done anything close to an unbiased test on this though. It just seems to be how it works out when I'm paying attention. Same with amp circuits. The more unconfounded (series resistance, voltage dividers, extra padded stages and reamping, etc) the more dead the action seems to be in my hands. A simple amp with good power tube overdrive through efficient speakers is always something I like and I can feel the difference. Even when clipped and compressing.

[Steve Conner]

All other things being equal, efficient speakers tend to have a frequency response with wild peaks and dips, making for a more lively and exciting sound.

There is a good reason for this: the manufacturer quotes the efficiency at whatever frequency it's highest. So the easiest way to make an "efficient" speaker is to engineer a massive peak in the frequency response, which is done by using a thin cone with poor damping.

You can also get speakers engineered for a flatter response, like the Eminence Beta series. These sound dull and dead on a bad day, "smooth, fat and jazzy" on a good one.

In the era of classic guitar amps, I don't think the distinction existed: the speakers were all designed for efficiency first, and guitar amps, table radios, organs and radiograms all used the same ones.

[soundguruman]

As a side bar... If you stuck a speaker with three dB more efficiency (not hard to find) into the HRDeluxe it would be LOUDER than the HRDeville. The actual volume of either amp, speakers being equal, would be something just under two dB difference. So DO just pick the amp that sounds best to you.

Chucky is right on.
Don't be obsessed with wattage. A 40 watt amp breaks up easier than a 60, and has more crunch than a 60 watt at a lower volume.
And if you were to put an EVM 12L in the HRD, it would be way louder than a Deville.

But, both amps are great sounding, when you do something like a Fromel Kit to it...
Fromel Electronics
Just by putting good parts in, instead of stock parts...these amps sound killer, better than you ever dreamed.
Metal film instead of Carbon Comp, Silver mica instead of ceramic, hi fi filter caps..etc...the difference is night and day.
Sounds just as good as any Boogie.

[Chuck H]

Sounds just as good as any Boogie.

That's almost like damning with faint praise! I actually think that most high gain Mesa products do the uber gain thing alright. But for clean and overdriven tones I'll take a stock HR amp over a Mesa product any time.

[soundguruman]

Yes it's a love hate relationship.
I would rather have the Fender myself. (which I do) I have not Fromeled it yet, but I plan on it...

[Rick Erickson]

With all due respect, I quote from the book of Fromell:
[ Plate Load Resistors - Replace all the plate load resistors with 5% 1/2 Carbon Comp resistors. This amp can develop a loud crackle/static that is caused by the plate load resistors. This mod fixes or prevents this problem and using the same carbon comp resistors found in vintage and boutique amps you add rich harmonic overtones.]

I get the impression that this guy, like most of the "guru's" selling their mods online, really haven't been doing this stuff very long. They all sell the same stuff - orange drop & silver mica caps, carbon comp resistors, power supply caps and upgraded transformers. Not to say there isn't some benefit from good iron, or a correctly functioning power supply, but replacing resistors & coupling caps with the latest craze is plain silly, and the chances of damaging a circuit board doing such shotgun mods is very high, even if you are an expert at soldering. FREDS's are a complete waste of time & money. Carbon comp resistors ARE a noise problem, not the cure. Orange drop caps are ok in general but they won't make your amp sound "tons better", probably won't change anything except your wallet thickness. I see so many failures with Silver-Mica caps that I routinely replace them with 1KV ceramics in any places where they have to block DC or handle high signal levels.
The major source of static noise in any new amp is the tubes. There are very few manufacturers making reliable 12AX7's these days, and power tubes are just as bad. Not that the tubes I was getting in the 80's were much better - the ones now marketed as NOS USA... we still had to weed through them to get reliable ones. I steer clear of any new manufacture "re-issue" tube with an old known brand name. I really hate telling a customer that the magic bean tubes they bought are junk, but it is quite often the case. Sorry - just felt a need to rant about this stuff one more time.

RE

[pdf64]

'but replacing resistors & coupling caps with the latest craze is plain silly, and the chances of damaging a circuit board doing such shotgun mods is very high, even if you are an expert at soldering'
That's a very good point.

'Carbon comp resistors ARE a noise problem'
Thinking about it, for PCB amps (a least single sided) it may be good practice to use turrets in the PCB to mount consumables such as carbon comps and electrolytics.
Pete

[soundguruman]

'but replacing resistors & coupling caps with the latest craze is plain silly, and the chances of damaging a circuit board doing such shotgun mods is very high, even if you are an expert at soldering'
That's a very good point.

'Carbon comp resistors ARE a noise problem'
Thinking about it, for PCB amps (a least single sided) it may be good practice to use turrets in the PCB to mount consumables such as carbon comps and electrolytics.
Pete

Since I am a fairly experienced guitar and bass player, AND a pretty seasoned Fender Tech,
AND a fairly well rounded pro sound engineer, recording engineer, I can give you my
impression, from my own experience...

When I did this for the first time, I was 100% skeptical that the sound would be improved...
And when I finished it, I was 100% impressed.

The parts provided are 99% stock values, and there are only 4-5 very small tweaks to the circuitry...
And so what you are doing is rebuilding the stock amp with much better quality parts.
Still maintaining a stock design, not a radical change at all. The changes are small.

Fromel provides some nice Carbon Comp plate resistors, which I did not use.
I used my Metal Film 1 Watt instead, because of personal preference.
And furthermore 1 watt Metal Film for the preamp cathodes would be my choice also...

The circuit board was not damaged, but this is not a job for a beginner,
I highly recommend that a professional tech install this kit, rather than DIY.
You should also have test equipment to verify the operation and bias settings.
The installation was 100% clean, and the board was completely DE-fluxed, etc...
It looked just like the factory built it that way--no slop anywhere.

The silver mica caps would be my choice. I have had 0 problems...
Except in a 1962 Collins 5000 watt AM radio transmitter, that's the only time
I needed to replace a bad silver mica cap.
The -985 volt bias circuit had failed...the snubber shorted and the 9.9 M ohm
stopper burned open.

Then the power supply caps are replaced with F&T..
The first power supply cap is doubled to increase stiffness, and this kills some
of the ripple.
I really don't like those Illinois Capacitor electrolytics...I think they sound rough.
All I can say is "grainy."
And I don't think they last very long, IMHO.
I like a HiFi cap, that sounds silky...smoother.

Then it was that the customer choose an Eminence Texas Tornado and an Eminence
Bayou Blues, but I would have gone with EVM 12L...which I think is the best guitar speaker
on the planet. I like cast frames better. And I like my 40 watt amp to stomp butt on
60 watt amps...it amuses me.

Fromel leaves the bias colder, ignoring this I set the bias hotter.
I would have liked adjustable bias in the kit, but Fromel did not supply that.

AND the last thing I like about the kit was that all the parts were there, all ready to go.
I did not need to research or order a bunch of parts, it was all done for me.
AND I received a step by step check list, which was pretty cool.
This saved me time and effort, I don't know if it saved much money. But it was darn convenient.

My end impression, just what I noticed immediately:
A. there was more gain and more sensitivity, with less mud.
B. the tone of the amp was noticeably better, sparkling highs and cleaner deeper lows.
C. noticeably less noise, less hum, less hiss.
D. the tone stack had a noticeable increase in performance, the tone controls worked better.
E. the reverb (where applicable) sounded better
F. I liked, personally, the overdrive was more useable- to me. (subjective)
G. the high frequencies sounded "percussive" as opposed to being "bland."

After this, the customer added a Mercury output transformer, which was wound just for whatever amp...
And it was a very nice transformer, very nicely made, with Teflon leads. And a really nice baked red powder coat finish.
So I think that again the highs and lows were improved, and the whole thing became a lot more hi fi sounding.
But I don't think that the headroom increased. That claim may be imaginary. At least in my own personal view.

At the end, with $700 spent , the amp sounded pretty sweet...
BUT it sounded sweet to a professional guitar player, or a sound engineer.

Would a beginner guitar player, or the average person notice all this tonal improvement???
OR appreciate the improvement???
Probably NOT. They would probably not notice or appreciate the difference at all.

The improvement or difference is subjective, and in the ear of the beholder, only.

[pdf64]

Thanks for the added detail.
I can see that a big benefit for such a kit is that all the parts are selected to fit the board, that would be a big PITA otherwise, even just for the electrolytics.
Not to disagree or denegrate the mod kits, but it would be interesting to get an assessment of how much of these benefits were attributable to the wire link that turns the mid control pot into a variable resistor?
For me, it's an essential mod to any 5F6A arranged tone stack and acts to makes the controls more usable and user friendly.

'I highly recommend that a professional tech install this kit, rather than DIY'
Definitely, it looks a significant task requiring the correct equipment and skills; I'd want a vacuum desolderer or something before taking it on.
Pete

[Jazz P Bass]

The absolute main item of this 'mod' is the speaker.
Add all of those components to make the amp 'perfect'(whatever that is) & play it through the Fender speaker.
It will still sound like ass.
Replace the speaker & wallah.
Good sound.
Now, what I would like to see is an amp that was resoldered, pots, sockets & jacks cleaned & lubed & a new speaker.
Wallah.
Good sound.
Is it perfect.
Probably not.
But then again, it's a guitar amp.