Amp Idea - Is it possible?

[yawny]

Well in my other thread i had the idea of a Tweed Bassman type circuit switchable to a lower wattage mode, probably 5w, that would make it act more like a Champ of other small tweed. I know this is possible, as far as the power cut goes.

However, is it possible to preserve tone with the power cut? Not necessarily the exact tone of the larger amp, but for the cut power mode to sound like a good little 5w tweed, not a muffled, muddy, larger amp.

Another little idea for this amp: the complete amp sould be a 4x10, 2x10, 4x8 etc etc, but would it be possible to switch to one speaker playing mode when switching to the power cut mode? Or would this have to be a separate switch? I assume this can be done, but I could be wrong.

Sure, this idea is pretty much one amp doing the job of a bedroom and gigging amp, but it's at least worth a discussion i think.

Feel free to comment, I'd love to hear any input

[randelli]

Anything is possible; but that would end up being a crazy expensive amp to have built. Just the R&D would make it prohibitive for a one-off build.

You would be better served to buy an attenuator to do what you are asking.

[River]

Speaker configurations aside, This amp suits my similar requirements admirably. I get great tone at volumes you can speak over in a normal voice at 12.5 watts. At 50 watts, I can rattle the dishes out of the cupboard.

Fender Pro Tube Reverb | Ampwares

[yawny]

Hmm, would it really be that difficult? At the very least it would be incorporating a power cut switch, but i guess that i'm not sure how hard that is. the speaker switch i think would be a matter of wiring, just using two of the taps on the OT, one for the individual and one for the group, correct?

Do you think 12.5 would be low enough for a dorm situation, River? I was looking for something voiced more like a tweed, but the Pro Reverb could work.

[River]

Originally Posted by yawny

Do you think 12.5 would be low enough for a dorm situation, River? I was looking for something voiced more like a tweed, but the Pro Reverb could work.

The clean channel sounds like a Deluxe Reverb. The gain channel sounds like a tweed Bassman, to my ears. It does early Zeppelin at volumes lower than two people having an animated conversation, no sweat.

For dorm use, at 75 pounds it would be hellishly difficult for someone to walk off with.

[yawny]

Originally Posted by River

The clean channel sounds like a Deluxe Reverb. The gain channel sounds like a tweed Bassman, to my ears. It does early Zeppelin at volumes lower than two people having an animated conversation, no sweat.

For dorm use, at 75 pounds it would be hellishly difficult for someone to walk off with.

Well then, I'll definitely keep it in mind if my overly-complicated amp design never reaches fruition.

And yes, i'd imagine 75lbs. would tend to deter most would-be thieves. Which is always a plus

[River]

Originally Posted by yawny

Well then, I'll definitely keep it in mind if my overly-complicated amp design never reaches fruition.

And yes, i'd imagine 75lbs. would tend to deter most would-be thieves. Which is always a plus

They're great amps, and that's not just my opinion. Quite difficult to find, but reasonably-priced nonetheless.

I plan on getting an extension cab for it, which for me personally would be a better solution than a huge combo with speaker selection.

[yawny]

Originally Posted by River

They're great amps, and that' not just my opinion. Quite difficult to find, but reasonably-priced nonetheless.

I plan on getting an extension cab for it, which for me personally would be a better solution than a huge combo with speaker selection.

I doubt I've ever seen one, and they weren't in production long were they? Maybe I can find a good cheap one.

And I like a good extension an too. The only reason the 4x10 was suggested was to keep with the spirit of the original Bassman, since that was it's most common form.

[River]

Originally Posted by yawny

I doubt I've ever seen one, and they weren't in production long were they? Maybe I can find a good cheap one.

And I like a good extension an too. The only reason the 4x10 was suggested was to keep with the spirit of the original Bassman, since that was it's most common form.

Just three years, apparently. The Pro series is still around, but I haven't seen any of them spec'd with as much flexibility as this little puppy has.

I'm with ya on the 4x10 - that's what my cab will be.

[yawny]

Originally Posted by River

Just three years, apparently. The Pro series is still around, but I haven't seen any of them spec'd with as much flexibility as this little puppy has.

I'm with ya on the 4x10 - that's what my cab will be.

Strange that they would scrap an amp like that. Seems like it has way too much flexibility to kill off. Guess they needed the factory for more overpriced Tweed RI's.

And he 4x10 is classy, they don't make them like that anymore, especially in combo form. IMO, they make you look cool.

[onioner]

I said it over on your other thread, but I guess I'll say it again. The issue you'll have with your amp idea is that it's not just a matter of cutting power. You are asking for at the very least two power sections, and quite possibly two preamp sections as well. It's not impossible, but you're basically cramming two amps into one chassis. Doesn't sound like a good idea to me.

If you want to cut power at the end, that can be done, but that gets back into attenuator or power scaling land, which it sounds like is not what you want.

There are lots of amps out there these days that offer power cuts. I don't know of anything Tweedish, but I've yet to find any that I find remotely satisfying. Doesn't mean they're not there. I just haven't found one. Granted, I stopped looking, as I decided it was silly to ask an amp to do too much...

[yawny]

And that's what I'm looking for, a power cut that doesn't destroy tone. Not two power sections, not two amps, but a circuit or modification to a circuit that allows it to retain tone, or at least provide a different but not worse tone, at a lower power output. Even if it isn't a feature on any current market amplifier, it has to be possible.

[Cygnus X1]

Get a Champ.
Get a Bassman.

Then a good A/B amp switcher.



I once had someone ask me to build a Fender and a Vox in one chassis.
It took a lot of explaining to have me say, the two are so different it would require a true split amp, two power transfromers, two output transformers, two preamps...the whole bit.
And the head would weigh on at easily 80+ Lbs not to mention the insane cost involved.

Bassman power section is completely different from a Class A Champ.
Preamp section isn't even similar.
You're looking at the same challenge IMO.

[yawny]

I wasn't aware of the significant differences, I'm not well-versed in readin schematics or in general knowledge of amp info.

What's your opinion on the power cut though? Or the speaker idea? Let's say I drop the champ aspect of it all together.

Does that change anything or am I beating a dead electric horse here?

[Cygnus X1]

Well there is power scaling.
But I'm not a fan of choking an amp back...by any means except volume controls.

[yawny]

I've never used an amp that did a satisfactory job of using it. It always seems just that, choked. So should I just continue searching for a good tweed or a good little circuit to use? Anything to recommend?

[onioner]

Originally Posted by yawny

And that's what I'm looking for, a power cut that doesn't destroy tone. Not two power sections, not two amps, but a circuit or modification to a circuit that allows it to retain tone, or at least provide a different but not worse tone, at a lower power output. Even if it isn't a feature on any current market amplifier, it has to be possible.

Honestly, I don't think that what you're describing is possible. Perhaps the end results, but not the method. You can't just modify a circuit to produce drastically less power (and expect it to sound good). That means a different power section. There are amps out there that are intelligently designed so as to offer different power sections in the same chassis, but it's limited, and IMO, excessively complicated.

The simplest, most effective, and quite possibly cheapest method is to have two amps... Plus, that's the most fun way too.

So, if you can, bring the bassman with you, for when you want the power, and get a Champ or something for when you don't.

[River]

Onioner: I like the way you think. Also curious as to any comments you might have on how Fender implemented power scaling on my amp, 'cause I sure like the way it works. http://ampwares.com/schematics/Pro_Reverb_Schematic.pdf

As far as innovative dual-amp designs go, I've got one of these on order. Not exactly what Yawny is talking about, but it is "two amps in one" which, when blended together, sound, well, delicious. Home Page

[yawny]

Well at the least this has been pretty informative. Maybe if I decide to get a degree in EE I can make something like this for myself one day, but for now I'll settle with a little Champ-type amp.

P.S. The Rude Mood seems pretty cool.

[onioner]

Originally Posted by River

Onioner: I like the way you think. Also curious as to any comments you might have on how Fender implemented power scaling on my amp, 'cause I sure like the way it works. http://ampwares.com/schematics/Pro_Reverb_Schematic.pdf

Man, I can barely follow simple schematics. That thing is so far over my head that it aint even funny.

That said, I can hazard a guess. This is mostly just based on the fact that it's got two 6L6s, and your description of how it sounds. I'm thinkin' that when running at 12.5 Watts, it's running class A, and biased fairly low, so you're not getting a ton of power from that one tube, and you're getting a good bit of breakup. When running at 50W it's using both tubes in push/pull configuration, but biased much hotter, so you get a whole ton of headroom out of it. Just a guess though. I'm happy when I can follow simple amps. Get into the whole multi-voicing, and power switching, and lots of switches and knobs, and it just makes my head hurt.

That Rude Mood does look pretty cool. Curious to how it works. Wondering if it's one power section sharing two preamp sections. Shrug. I dunno. It's certainly possible to have two or more voices in an amp (as evidenced by the vast numbers of multi-channeled amps), but they tend to have a good bit in common. The less they have in common, the less it makes sense to share a chassis. From the little I know about that amp, seems like it's goin' about things in a completely different way than your normal two channel amp.

Mayhaps someone can come along and explain that Pro Reverb. I'm curious as well.

[rocknhorse1]

The Rood Mood is built by member Rendelli here on the forum, and it is two separate power amps, and two separate preamps...two amps in one chassis. It's a pretty innovative design.

There are many other things that have an impact on this "low volume nirvana"..... The speakers.
You cant get a speaker to sound at low volume like it does when it's being pushed hard. This has a huge impact on tone and coloration of the tone, and feel.

V V R is the #1 one low volume method out there right now. LPV and Case24 have it installed on their Tweed Deluxe 5E3 clones and really like it.
I have a half power switch on one of my amps and I never use it. It doesn't make the amp any quieter really....very little.

[onioner]

Originally Posted by rocknhorse1

I have a half power switch on one of my amps and I never use it. It doesn't make the amp any quieter really....very little.

This is my experience as well. Granted, the only amp w/ such a feature that I've spent a bunch of time with is the Dual Terror, but I've messed around with others as well. Mostly it seems to just affect breakup, both in terms of when it breaks up, and how that breakup sounds. Not useless, for sure, but not very helpful in terms of volume control either.

[yawny]

Originally Posted by onioner

This is my experience as well. Granted, the only amp w/ such a feature that I've spent a bunch of time with is the Dual Terror, but I've messed around with others as well. Mostly it seems to just affect breakup, both in terms of when it breaks up, and how that breakup sounds. Not useless, for sure, but not very helpful in terms of volume control either.

Well it falls in with the rule then right? Ten times the wattage equals twice the volume and vice versa. Rock horse, you have a good point with the speakers, it's probably the most overlooked aspect of the half power switch. Also, what is this VVR?

[Cygnus X1]

VVR=Power Scaling.

[rocknhorse1]

Originally Posted by yawny

Well it falls in with the rule then right? Ten times the wattage equals twice the volume and vice versa. Rock horse, you have a good point with the speakers, it's probably the most overlooked aspect of the half power switch. Also, what is this VVR?

There are a couple different ways to "power scale" or install a V V R into an amp.
You can just put it on the power section, or you can put it on the preamp and the power section. You can also put it on the power section, and install a post phase inverter master volume.

It operates on the B+ voltage to the power tubes, and the preamp tubes if you want.
It would make sense to me that an amp with no master volume would benefit from having both the power section and the pre section with the VVR on it.

I asked Nik from Ceriatone what he likes on the JTM45 that he sells (which is supposed to be a non-master volume amp if going to the original specs) he said he likes them with the VVR on the power section, and a post phase inverter master volume installed....so my logic go's out the window there...BUT, this is another one of those things that is circuit dependent, as well as the personal taste of the end user. Try all the different ways on the amp you want, and then you will know.....I know, not very practical.

There is no magic bullet. It is what it is, and you will always make compromises.

**EDIT** I wonder if any amp designers have tried to design an amp specifically around a VVR system. I mean design the amp to whatever the VVR would dictate. Maybe they do this already, not sure.

[randelli]

It sounds to me that you really want one amp that sounds great at both gig and bedroom volumes - with no noticeable degradation of tone at the lower volume. That is it in a nutshell, right, once you strip away power switching/speaker switching. The problem is that most amps are only good (some are great) at one or the other. I happen to very much like the way my RUDE MOOD sounds at both ends of the spectrum.

The RUDE MOOD is 2 separate 15W amps , seriously, in one 45 lb 2x10 combo. The RUDE is plexi/hiwatt and beyond - with a master volume that acts more like a fader so your gain and tone are not effected by volume. The RUDE is a blackface with tremolo and reverb. This gets loud enough to gig over the most insensitive drummer; and quiet enough to provide great tone at baby sleeping levels.

The RUDE MOOD is not a 2 channel switchable amp. That would be cool enough; but the purpose of the RUDE MOOD is to combine BOTH amps at the same time at varying levels to achieve the tone you are craving.

Many players play through multiple amps that are blended by the sound tech to get their sound. I would like to do that, too, but I have no way near enough extra cash around to purchase 2 great vintage tube amps, much less the constant upkeep they demand. Plus, not having roadies makes that whole thing impractical.

So, I knew what I wanted in an amp, could not find it anywhere, and was too stupid to know it could not be done - so I did it!

Is this the right amp for you? It might be, maybe not, only you would know that. Check out my links below and listen to some video. Search MLP for some great reviews from mudfinger and others from the LA Amp Show. Ask River in a few weeks when he gets his own RUDE MOOD.

[yawny]

Again, more food for thought.

I'll definitely give it a look Randelli.

[rocknhorse1]

Randelli, does each speaker work for each side of the amp? Meaning are they seperate to the Rude, and Mood sides? Are they both the same, or different speakers for each side?

[randelli]

Each side has it's own preamp section, output section, OT and dedicated speaker. The RUDE (not rood ) has an EL34 into ceramic. The MOOD has a 6L6 into alnico.

magic!

[rocknhorse1]

Originally Posted by randelli

Each side has it's own preamp section, output section, OT and dedicated speaker. The RUDE (not rood ) has an EL34 into ceramic. The MOOD has a 6L6 into alnico.

magic!

Sorry for the misspell. Fixed.

Thanks for the info. That does sound like it would be pretty sweet, especially blending the two...lots of tones.
Two output transformers!