Breakup & spkrs/ basics.

[Sea Chief]

Hi- Ive built 2 tube amps (and own 2 others) and satisfying to build and hear come alive etc, tube OD has still utterly eluded me & a mystery (not then say from the only time in my life Ive played an amp OD: turning a SF Champ up I had the pleasure of doing 28 years ago; added bewilderment being that it broke-up/ OD at 6 on that amp, & was more than Ive ever got cranking my 2 builds up).

1st build a 5E3: so bassy and loud I couldnt possibly turn it up, ever: the one time I did I was nr accosted by a neighbour. I did hear some 'medium' break-up but only for 2 minutes before I was shouted at & threatened (added mystery is it wasn't an appartment but at a BIG friend's house with 4 acres between it and neighbour/ it was so loud it hurt & I couldnt possibly have continued standing next to it even w'out harrasment for more than 10mins.. and Ive seen Dinosaur Jr live/ I know/ I can do loud).

So I sold off parts of that wasted build & built a 'Champ'. I added a tone control (humB's are too dark w'out tone at min 8 for me) ss rectified: so poss a 5F2-A of sorts then (I cant remeber exactly what it is!). Turning up didnt provoke neighbours but I get near to no OD even with a real SG, at dial 10. I did get some mild OD with a danelectro with its super hot pickups once (I guess the reason) but that's sold/ cheapo chinese gtr. It is going into a peavey blue marvel 8 ohm, 50w, 12" ext speaker cab, and not a std 6" or 8" tiddler.

(The other 2 amps: a wem 15w dominator- I cant turn this up even to see if I get break-up due to upsetting neighbours.. but I assume so from the youtube clips, maybe. Other a 40w Crate 6L6 2 channel beast.. I can get some mild break-up!! but marginally so and its only preamp OD I got by utter fluke/ modding ch1 by linking ch2's MV up to it to try and cure an amp noise issue).

Q: if I were to put it the 'Champ' into a 6" or 8" tiddler, instead of the (bog std) 12" 50w spkr.. would I expect to get more (even some at all in my case) OD at dial 10? or has the physical size of the spkr no bearing on the OD sound? If not, what is?

Break-up is a holy grail to me.. 10 years Ive spent trying now. My brain nr explodes when I read " it breaks up too early.." jeepers if only if only I could hear just some..

S.Chief.

[Chuck H]

There's something a little different about your "Champ" if it's not breaking up with HB's. The way you speak of it I have to wonder what the actual schematic is.?. I think you should retro design it and post a schem of the ACTUAL circuit for analysis. PLEASE do not post a 5F2A schematic and explain "I think it's mostly like this except for..."

The Watkins should sound great cranked up. And there's a way to do it too! Just build one of these. It's an attenuator circuit that will lower the output of your Dominator to about a watt.

EDIT: Oh... To answer what I think your actual question was, the speaker, assuming it's not a grossly improper load, shouldn't have any notable affect on breakup. Speakers themselves aren't often responsible for much clipping at all. When we talk of how a speaker sounds clipped I think it has more to do with how it sounds with a clipped wave form than actually overpowering the speaker. Some guys say they like speaker clipping, though I'm not convinced they've ever actually heard it. Actually clipping the speakers generally a bad idea.

And P.S. The Blue Marvel isn't my favorite speaker, or anyone else's. That's the nicest thing I can say about it. Once your getting your clipped sound you'll almost surely want to replace it. They tend to be harsh and one dimensional.

[J M Fahey]

Weird .

I wonder where you may live.

It must be a REAL quiet place.

[Sea Chief]

Hi Chuck.

I have a feeling the reason its not breaking up might be due to the PT.. but maybe not: I haven't enough knowledge of the consituent parts of a circuit creating 'break up' to state as much it is this PT (also s'one gave me the PT in order to get my amp at the time/ the 5E3/ to break up "sooner" so he thought- I'd stripped the amp down by then so sick of it I was & decided on a small amp with the PT, and here I am.. though I cant remember what I built!! so I cant give you the schematic! It's a simple P-to-P single ended 12ax7/ 6v6 Champ defo tho, with a ss rectifier, and a tone knob that works quite well. Its got a decent hammond 125ESE OT in, & clean sounds are pretty good- a nice woody tone in fact).

The PT has two secondaries of 254 -0- 254, and a rating of 60ma. Now, whether that is completely & ridiculously unsuitable for a Champ might the explanation.. but his 'break-up sooner' plan, and also this very PT is used by Vyse amps in 2x el84 15w type circuits (which I would expect as buyers would surely want there to be available in a small simple tone-based gtr amp, amp break up.. and not just the hint of it as I have only achieved.. but proper OD tones after say dial 7 minimum) hint at it being a capable/ proper gtr PT at least, so Id expect therefore as its not a twin reverb monster, and its use by a decent amp-maker, to be capable of delivering the goods.

So you see Im so confused. If only I could establish why (none), I could, perhaps begin to understand how.. SC.

[The attenuator is certainly an idea- but Ive heard they arent especially good for the amp, and one false mpve and BOOM Ive given the pensioner across the street a cardiac arrest. I need to investigate tho/ and poss a plan for the WEM whcih would surely be fantastic, if I could if I could..].

S. Chief.

[Chuck H]

Weird .

I wonder where you may live.

It must be a REAL quiet place.

I thought the same thing! In a home, in a neighborhood where the houses don't share walls, a fifteen watt amp (which is probably putting out more like twenty watts cranked) is usually manageable in the back room with no windows open and no one home Also... I gigged for years and yet after being away from playing loud for a decade I was still a little shocked and jarred sitting front of my fifteen watt amp cranked up. But once you get use to it there's no going back. I use my attenuator begrudgingly anymore.

[Chuck H]

It's not your PT either. That PT should give you about 290 to 300 plate volts and that's fine for a single ended 6V6. I suspect there's a minor mistake in your wiring that's reducing gain. You don't seem like you're that into the work so troubleshooting would be a frustrating affair. A Champ isn't a modern, uber gain monster for playing Tool or RATM riffs or anything, but they were used on A LOT of classic recordings to get sloppy, gritty tones in studios. As were the Dominators! I've always wanted to build one. I love Brad Paisley's punchy, defined tone (though I don't play country at all) and I remember noticing that some early Dr. Z designs were very "Watkins" like.

Have patience and with a little work you can certainly get to where you want with the amps you have.

The only danger of attenuators is that they must be plugged in. Obviously any tube amp is in danger without a load. And having an extra box between the amp and the speaker increases the possibility of mistakenly running the amp without a load. The attenuators themselves aren't a problem. It's the additional possibility of user error that is the problem. Attenuators have a bad rep due to a misunderstanding of the system. Here is Chuck's attenuator gospel:

Using an attenuator will only wear out your tubes faster because you'll be cranking the amp higher and more often.

Attenuators are usually gentler on an amp than an actual speaker load.

Never use instrument cable to connect your attenuator to your amp and be sure everything is connected properly each time you use it. It's probably a good idea to turn your guitar up just a little and test for sound before cranking up and whacking out power chords through your amp into a potentially open load.

Don't believe what you've heard about attenuators from people that clearly couldn't understand them. Many famous players tones have been achieved using some form of attenuation.

An amplifier must be in good working order to survive frequent cranked use. Good filters, tubes and clean contacts for all jacks. This is often untrue of vintage amps. If you crank a compromised amp into a speaker often it will eventually fail. Likewise, if you crank a compromised amp into an attenuator often it will eventually fail.

If you can make toast without shocking yourself then you have the good sense to replace a broken toaster or at least the sense to unplug it before jamming a fork inside to get your toast out. You qualify as someone that can safely use an attenuator.

[Sea Chief]

Weird .

I wonder where you may live.

It must be a REAL quiet place.

Well, yes but a normal village in UK but a big house nearest neighbour 75yds away. I wasnt expecting such ferocious volume in order to just find some OD (or someone to come all of 300 maybe 400 yds away to nr threaten me within 2 minutes of playing- but so loud it was I wasn't totally surprised tbh). Trouble is with diy amps Im not to know Ive made an error in the build resulting in an added ferocious ammount of volume somehow. That would give me an answer if so. But Ive trawled this idea as conceivable.. and afaict it isn't/ its how a 15w tube amp should sound at vol 7.5. If so, then how on earth folks can shoot video of them next to a 5e3 cranked on youtube without me seeing the walls shake, the cam distorting so badly, them physically uncomfortable, and their neighbours whacking on the door behind them adds to the mystery. I just dont understand any of this. Only way I could know is go 70m to london, plug into a real 5E3 in a shop, turn up to 7.5 and find out how loud it is/ but I wouldnt be allowed to do this anyway even if I had a spare day & £30 fuel and £15 parking.

SC.

[Sea Chief]

It's not your PT either. That PT should give you about 290 to 300 plate volts and that's fine for a single ended 6V6. I suspect there's a minor mistake in your wiring that's reducing gain. You don't seem like you're that into the work so troubleshooting would be a frustrating affair. A Champ isn't a modern, uber gain monster for playing Tool or RATM riffs or anything.. Have patience..

Hi Chuck. Dont get me wrong Im not after any such hi-gain stuff at all. I'm just after that 'sweet spot' OD, ie as you allude to with 'sloppy, gritty' etc. Nothing more. Ive once played like this, when I was 17. Im in my 40's now! 'Patience'.. Ive expended so much with the 3rd build and so much work on the Crate to find a noise issue.. and trying and trying to understand why I'm not getting what all others seem to get as a mere matter-of-course & "just turn the vol up". Only when I figure why its not happening, can I then figure out how perhaps. That's the point of the thread. Im trying to narrow the reason down. I thought it must be the PT, but you say I should be ok with it -& its used by Vyse amps- so logic says it cant be the PT 'underpowered' or suchlike. If there was an obvious wiring fault, then the amp wouldn't sound fine albeit clean as clean up to 9, and Id have a bad hum or a pot working oddly or something. it runs warm as expected. The tubes light as expected. All is as expected/ it runs well. But clean as a whistle.

So Ive been reading up on speaker sensitivity as a possible reason Im not hearing any break up. Could it be the speaker, a 50w, 12", 95db is totally and utterly wrong? if I were to use the 'standard' 8" 25w say jensen xyz... then that would sound completely different and the amp would sound correct & broken up cranked?

[Chuck H]

It's not the speaker. I promise. All the speaker is doing is telling you what the amp is saying. It can't affect how much the amp clips at a given volume setting. This is a fact, so you can ignore the speaker as a possible part of the addressed problem.

A 5F2A type Champ with 290 volts on the 6V6 should growl like a jungle cat at vol. 5 with humbuckers. So something isn't right. Just because an amp makes a good sound in one regard or another doesn't mean it's working correctly. Further, can you be sure of your entire system? As in your guitar? Do you have another HB equipped guitar or can you borrow one to try out in your amp? If you only have the one, and you never crank up your other amps or otherwise have specific outside reference to relative "correctness", how can you be sure of anything? If you have a weak signal from your guitar that would need to be addressed. But the circumstances are still so vague that I'm only suggesting where one might start to look for a low gain problem. Which you obviously DO have. The PT and the speaker are almost certainly on the other end of the circuit from where the problem is.

[ric]

I wonder if a pedal in front of your amp would give you the driven tone you want at lower volume? Assuming these folks here that are experts can walk you through knowing things are ok with the basic functioning of the amp.

[R.G.]

Speaker "break up" is a consequence of the mechanical nature of the speakers - the mass of the cone, the flexibility of the surround and spider, the cone stiffness and material damping characteristics, all those details. Break up happens a couple of ways. One is when the drive is so large that the cone is driven to the limits of its mechanical movement, literally clipping, and another is when the cone has a big, fat resonance that either hits the movement limits or actually makes the cone flex in the middle between the voice coil and surround. There are others.

But almost all of these require very large drive levels, up at or near the power limit of the speakers. Most guitar speakers are quite efficient in terms of electrical to acoustic power (well, for a loudspeaker; they're all efficiency disasters, but they're better at efficiency than hifi speakers) in that they do a lot with a watt. The standard way to measure speaker efficiency is the SPL delivered by one watt of drive at 1M away from the speaker, on axis. Guitar speakers tend to be in the 95-105db range. That is a lot of racket from one watt. Ten watts moves you to the 105-115db range and things are getting seriously loud. 100W gets you handily into jackhammer, machine gun, and jet engine territory.

The net is, you don't get speaker breakup from non-defective normal speakers until it's near it's maximum power levels and that's LOUD, not just sounds pretty loud in a room.

This is all just to reinforce the message - it's not your speaker(s) that are the problem. Your amplifier is staying undistorted.

By the way, this is usually a good thing. Nearly all guitar amps these days are used with pedals, and having the amp turn into a sonic mixmaster, blenderizing the delicately shaded renditions of a pedal chain is not the best way to use pedals. Guitar amps are pedal friendly to the extent that they impart their own special tone flavoring to the mix, but do not destroy the pedal additions too. It is quite difficult to get a decent reverb, chorus or flange with an amp which is itself distorting . (At least I think it is, to my ears.)

If you are one of those people who don't use pedals, but just want the guitar and amplifier to be your sound, ignore this. But there are two clearly different paths.

[Chuck H]

Your amplifier is staying undistorted.

By the way, this is usually a good thing. Nearly all guitar amps these days are used with pedals, and having the amp turn into a sonic mixmaster, blenderizing the delicately shaded renditions of a pedal chain is not the best way to use pedals. Guitar amps are pedal friendly to the extent that they impart their own special tone flavoring to the mix, but do not destroy the pedal additions too. It is quite difficult to get a decent reverb, chorus or flange with an amp which is itself distorting . (At least I think it is, to my ears.)

If you are one of those people who don't use pedals, but just want the guitar and amplifier to be your sound, ignore this. But there are two clearly different paths.

I sure as hell don't want to debate with you, but by these statements I infer that you're saying the amp, in the right circumstances, might be especially useful as it is. And I would agree with this. A Champ that is more pedal compatible. But this also advocates leaving a problem unsolved by virtue of the fact that any 5F2A that doesn't break up generously with humbuckers isn't working correctly. Just sayin'.

[Justin Thomas]

Isn't working correctly to who? I bet if Leo coulda made a Champ that didn't distort the way WE like, he woulda! Everett Hull would probably LOVE to get Sea Chief's amp & figure out how he did it! All those guys until Jim Marshall were always trying to get rid of that awful distortion...that our classic amps sound great when ready to explode is just a happy accident for us and the bane of all those old guys's existence. It's how we went from Champ to Twin.

That said, I was offered a Champ "clone" once for a really good price. I turned it down. Why? It was broken - "whereza crunch?" So, at heart, I agree with you, Chuck...

Justin

I also offered a guy half price for his Bassman head cuz it sounded like a swarm of coked up mosquitoes on "2." "But I had it hotrodded! Isn't it awesome?" No, it says Fender, not Gorilla. It's broken.

[Sea Chief]

If you are one of those people who don't use pedals, but just want the guitar and amplifier to be your sound, ignore this. But there are two clearly different paths.

Well, I use an OD pedal as Im forced to.. but its pap compared to the real thing. I won't ignore what you've written: its interesting to know more about spkrs and their limitations and cone break-up. Perhaps 'break-up' isn't the term I'm specifically concerned with, as Im near certain its the amp not distorting. Speaker break-up I guess is an advantage Im not even in a madman's dream of considering yet. I assume a 50w speaker, if a 5w amp is at max whether its distorting or not, would not 'break-up' anyway?

This is confusing me even further I think regarding speakers. I am going to consider the amp only I think and term it OD to distinguish it from anything speaker-related.. or my brain will implode.

[R.G.]

I sure as hell don't want to debate with you, but by these statements I infer that you're saying the amp, in the right circumstances, might be especially useful as it is. And I would agree with this. A Champ that is more pedal compatible. But this also advocates leaving a problem unsolved by virtue of the fact that any 5F2A that doesn't break up generously with humbuckers isn't working correctly. Just sayin'.

No issues to debate here. I am definitely not in a position to say what at 5F2 should do.

I was just noting (albeit in a rambling, moderately disconnected way ) that there is a decision to be made about where you want your distortion to happen. For people who use pedals and like what they do, a distorting amp can make that task more difficult. For people who appreciate and are willing to live with the limitations of using amp distortion, that's another path, and a perfectly acceptable one. All a matter of taste. I personally LIKE a bit of hazelnut syrup in coffee. My longsuffering spouse cannot stand the stuff. Both OK.

A 5F2 that doesn't distort with humbuckers may very well be not functioning correctly per other 5F2s; certainly not as expected, I guess. No issues. It's a problem to solve if you want the amp distortion, maybe an advantage if you're after something else.

Isn't working correctly to who?

That's kind of another way of saying what I meant but was not very clear about.

Well, I use an OD pedal as Im forced to.. but its pap compared to the real thing.

That's perfectly valid. As the smart folks have observed over the centuries, there can be no disagreement about matters of taste.

I assume a 50w speaker, if a 5w amp is at max whether its distorting or not, would not 'break-up' anyway?

Probably not. Speakers are funny. They're a vibrating mechanical device, and are prone to all the funny rattles, resonances, and other oddities mechanical stuff has. Quite a lot of speaker design work is trying to untangle that mess into something that has a more even response and less mechanical oddities. But a speaker running at 1/10 max power should not be into rattling territory yet.

This is confusing me even further I think regarding speakers. I am going to consider the amp only I think and term it OD to distinguish it from anything speaker-related.. or my brain will implode.

Think of it this way: Everything distorts if you push it hard enough.

Here's one that will make your head hurt: air distorts. When designing horn loudspeaker enclosures, one has to watch the air pressure variations in the area just ahead of the speaker element because there is enough pressure variation there in some horns to cause the air to begin responding nonlinearly. ACK~!!

But this can all be put into perspective by noting that although everything distorts, they tend to distort at different energy levels, and also in different ways. That is after all the basis of the debate about how tube distortion differs from solid state distortion, and also that there are good, bad, and indifferent versions of each. In fact, a single tube distorts differently depending on whether the grid is going positive or whether the plate is running out of voltage headroom - and also whether the plate is running out of current conduction ability.

It helps me to think of everything as having its own distortion characteristic. Germanium distorts earlier than silicon, and high feedback opamps distort differently, kind of sideways from both of those. Tubes are different yet, and as noted different on input and output. And that's OK - a chocolate cake needs many ingredients, all of which you can have too much or too little of, and some which are optional.