rnrss orates on Power Amplifiers

[rnrss]

Well, let's see, there's simple and then there's simple...

1000 watts? That's a little ambitious. Not in the simple category. Even if the circuit is simple enough conceptually, it's going to involve a lot of money and the consequences of a bad solder joint could be spectacular in the fireworks sense of the word. Crushing disappointment and financial ruin are not good memories to take from your first project.
Grey

Well if the money is an issue, and if you cant solder, and if a little setback is going to cause crushing disappointment, and financial ruin then you have no business building "anything" to begin with...

If it's a first project, then a more modest 10 or 20W amp would be a good bet.
Grey

No reason to bother building a 10 or 20 watt amp... Thankfully there are lots of very simple amps out here that have a very small parts count and they will give you substantially greater and better output than the amps this guy is pushing...

There are numerous small amps here and there on the web, but the pedigree of some of the mutts is questionable.
Grey

Now that wasnt a very nice thing to say now was it? Especially since I am the person who posted those other "MUTTS" that you feel have questionable pedigree...

In the running for Simplest Amp Possible is the Son of Zen. Two transistors and a few resistors. Can't beat that for simplicity. But...it runs seriously hot (by design) and requires a power supply the size of a Volkswagon.
Grey

Yes that is the industry standard what every amplifier manufacturer set their hearts on achiving in high performance state of art amplifiers... You did what they couldnt... Everyone has been trying to design their amps to run as hot as possible and they have failed miserable over the years but you ahve done it... gotta get em right to the edge of the soa and do 300watts idling or its simply no good...

Yeh and I feel so bad and financially ruined because I made the mistake of buying a mutt... and I hate to even admit it but my mutt runs at slightly above room temperature while driving over 800 watts into a 4ohm load at an ear crippling .15% max distortion 20-32k... and you would not believe it man these guys screwed up so bad they even forgot to put heatsinks or fans on it, and the most heat I can get from it is slightly above room temperature... and to make matters even worse, it idles at a bankrupting 12 watts...
I am so depressed...

One notch up the complexity scale is the Zen. A few more parts, but a lot more versatile in terms of matching with speakers. Not a bad choice.
Grey

Yeh these amps are a great choice if you like a barnburning, (get it grolins?), that is a barn burning 10 watts!!! that is >2.5% distortion at 2volts and thanks goodness it increases to >10% distortion at 20k at 10 watts... If thats what you like then the zen amp is just the amp for you... and as a special blue lite bonus, if you are a ham radio antenna builder you will have special sentiments for the High impedance deluxe super high pedigee amps because you are sure to enjoy building the matching networks required just so you can get the thing to work with your speaker... and then dont forget as an added blowout special you will also need to design a different network for each different speaker you want to put it on too... so you can be proud that you invested in a high quality, high distortion, high heat, high pedigree designs I guess... What fun!! Um errr...

Then again several orders down in complexity, in the lowest pedigree known to man is a really nasty little 50 and 60 watt amplifier right from the zero pedigree company who designs and manufacturers the transistors... Now that is no doubt the lowest mutt of all, and granted I realize this but I feel even the lowest mutts deserve to accounted for...

http://sound.westhost.com/project19.htm

http://home.mira.net/~gnb/audio/lm4780.html

Unlike the amps this guy is pedaling, these amps have and unsurmountable 2 more parts than the zen amp and they are really small cool running easy to build amps from the most worthless mutt company of all, national semiconductor, and they have a max distortion of .1% at rated output 20-20... but then like the saying goes you get what you pay for... Um... or do you?

There are many people on this site who are very much in the dark in these and other areas as well and have no clu that a well designed class ab amp is spectrally cleaner than a class a amp and they still spout the class a jibber... tests have been done to prove this... but that doesnt matter because they have feedback... LOL when ya want more sales create a mystery and solving a problem that does not exist... the idiots will argue about for years...

Then again most of them have absolutely no clu as to what happens to the motion of a speaker or the quality of that motion when connected to a hi impedance amp versus a low impedance...

How about grolins, you da man, I just got off da farm I dun know nottun...

So you get the honors, show everyone the math model and present to them how many db of garbage will be generated and combined with the original content of the source using one of your .25ohm output impedance amps driving a signal of 10 watts into a 4 ohm coil speaker load that with an eff of 108db/w/m... Oh and better yet lets also do one using one of your 15ohm output impedance amps on a 4ohm driver... Now lets do one for a .001ohm output impedance amp...

Can you even do it? Did you even think of it? Dont worry when you are finished I will cover for ya and correct your mistakes...

So whats my point? Welllll my point is, if you want lots of harmonics injected into your original source material as a result of the amplifier losing control of the driver then a High Z amp is just the thing for you...

If you want to precisely control a cone in a mannner that this cone will produce and move exactly according to what the program material is putting into it, (ie: put the preamp output on a scope and compare it to the cone movement to see if they match), If you want them to match then Hi Z is not going to achieve that for you... also if you are not using horns a hi z amp will not perform anywhere near as well as a low z amp... and you will enjoy lots of yelping at more robust volume levels...

Yeh yeh spare me the tube sounds better lingo... Just throw a resistor in series with a low z amp and presto you now have that wonderful tube sound...

I personally want to hear "EXACTLY" what is coming from the source, and I certainly do not want to have to build a matching network to tune my speakers like I would a freakin cb radio, and I certainly do not want a yelping speaker when I turn up a little bit to hear my favorite part...

Then there is also the lesson on why you want more than 10 watts on a speaker, 110db horns included, and then another lesson on the loudness of live instruments, but I will save that for another time...

Now you may feel that fresh off the farm is a really bad thing groalin, but on the bright side, at least we can discern the difference between a rose patch and a pile of sh*t...

I read the specs on most of the pass labs amps and I was nearly ready to say there is not one amp I would buy, but now I cannot say that as the aleph 0 I think it was would have been one I would have considered... but for the rest... better you than me...

By the way tell us how many of those amps you called mutts that you actually built or heard?

 

[Samuel Jayaraj]

rnrss, to say the least, the tone of your post is unwarranted. The lesser said the better, but I'd say that you have a long way to go before you come around the circle realising that pleasurable sound (and music) does not lie in better measurements with instruments that finally have no link with psychoacoustics. If I may suggest, please do not make a personal attack (like you have on GRollins, one of the most respected elders of this forum) on anyone with whose opinion you may differ. Finally, your reply provides no solutions to the question that begins this thread?!

 

[rnrss]

rnrss, to say the least, the tone of your post is unwarranted. The lesser said the better, but I'd say that you have a long way to go before you come around the circle realising that pleasurable sound (and music) does not lie in better measurements with instruments that finally have no link with psychoacoustics. If I may suggest, please do not make a personal attack (like you have on GRollins, one of the most respected elders of this forum) on anyone with whose opinion you may differ. Finally, your reply provides no solutions to the question that begins this thread?!

Well I guess that is your opinion and you have a right to your opinion... frankly you do not know what is and is not warranted...

You also seem to think that somehow my appreciation for music is somehow lacking from yours... and that is fine too...

You like so many other people of your persuasion feel you have some kind of an edge, obtained some kind of esoteric status that affords you the right to lecture me on psychoacoustics... To you I am a mere novice trying to gaze up from below at the wonderful circle of real music connesuers... and the fact of the matter is that you have absolutely no clu as to my background, experience, or where I have been... and the last thing you will ever convince me of is fanciful listening any more than you will convince me of ghosts and goblins... I would only respond with a question like show me... define "exactly" what that is... so if yo uare willing to do that I am willing to at least listen you out as to what you feel psychoacoustics is... and if you were able to really put criteria to this word what good would it do? I would only show you what specs in whatever equipment that would provide that kind of sound for you as you described... and if you like to listen to distortion hey "great" for you, but its hardly esoteric...

Oh I have no problem with people who's opinions are different than mine that is not the issue nor is it the reason for the "tone" of that reply... grolin knows why my tone is that way...

Lastly: yes considering his post, my post is relevant... I did exactly as the person requested and posted schematics... at least until someone decided to throw mud on them... open that door and I will go there with you too... and I really could care less if he is god... I judge by what I hear and see...

If you believe in psychoacoustics fine... but for me it is nothing more than a wonderful sales technique to capture whatever it is that is in your minds eye, real or imagined and equally as much a fallacy... You will "never" hear a trained listener use that term...

Now if you want to step into my world you will see how close your system will come to a live instrument 10 ft in front of you and forget the psycho part... just do the instrument, I have never heard a psycho instrument yet...

If you want to step into my world you will go to a live concert, a BIG one and go home to hear very nearly the same thing... and to do that you will need to reproduce the same levels and I am very sorry to inform you that it cannot be done with 10 watts or a hi z amp

I have never heard either of the 2 things I appreciate in my world produced from a tube or ccs reproducing system... Oh they have certain qualities that are very distinguishable, but I would never choose those qualities as something to be proud of in my world... on the other hand I can take virtually any vs amp add a fricken resistor tot he output and have the same as a hi z amp sound... but I would never ruin my amps df like that or destroy the low distortion sound I appreciate....

Hi z is great for musicians who want to create a sound by use of the harmonics but I guess it boils down to what do you want to hear being played back to you? The harmonics the musician made by running his guitar through a tube amp or the harmonics your stereo makes?

I want to hear the harmonics, (and do) that the musician made... and I consider the whole idea of psychoacoustics a form of no where land reasoning, all you guys talk like there really are mysteries in electronics and acoustics... I think not...

 

[Samuel Jayaraj]

rnrss, I choose not to be as aggressive as you are in my posting. I am glad to note that you acknowledge the right of a person to his own opinion. I give you the same right to your opinion.

Further, I do agree that most often equipment that add very little character of their own (read- the ones that measure well) do produce sound that is 'un'coloured. So you do get to hear what the artist and the studio team intended you to hear. Yes you do not doctor the sound, as much as possible. The only sad part is that this type of gear 'tends' to sound a little 'clinical'. Most often you wish it had a little more musicality, touching your senses, automatically making your body move, but.... they do make up with their big sound. Sometimes, certain parts of the spectrum sound larger than life in comparison to the finite boundaries of your listening environment. Turn the volume down and immediately the 'impact' is atleast slightly lost. In a nutshell they sound right from a given spl upward to another ceiling spl. Below that threshold they do not really touch your senses and above the threshold..... the reactions are different but everyone wants to reach out to the volume control and turn it down that bit.

On the other hand, high distortion equipment do add much colouration to the original sound. Sometimes this colouration is not at all obvious; yes, they can be very pleasant. When done rightly, these type of equipment tend to sound right even at very low spls. And if combined with very sensitive speakers, they are revealing, dynamic and life like. And you can obtain concert levels in your listening environment.

With either type of equipment, no one can reach concert level dynamic range even in the smallest of rooms!!

Belonging to either school is not unpardonable sin. And by the way I do own and rent concert gear and am knowledgable about both varieties of home gear, so I know what I am talking about.

 

[derf]

Further, I do agree that most often equipment that add very little character of their own (read- the ones that measure well) do produce sound that is 'un'coloured. So you do get to hear what the artist and the studio team intended you to hear. Yes you do not doctor the sound, as much as possible. The only sad part is that this type of gear 'tends' to sound a little 'clinical'. Most often you wish it had a little more musicality, touching your senses, automatically making your body move, but.... they do make up with their big sound. Sometimes, certain parts of the spectrum sound larger than life in comparison to the finite boundaries of your listening environment. Turn the volume down and immediately the 'impact' is atleast slightly lost. In a nutshell they sound right from a given spl upward to another ceiling spl. Below that threshold they do not really touch your senses and above the threshold..... the reactions are different but everyone wants to reach out to the volume control and turn it down that bit.

Are you sure it's low distortion amps that cause this?. I'd be more inclined to think it's probably the source and/or speakers, followed by components to a lesser degree.

Of course the impact will be lost at volumes less than "life like", pretty inevitable i'd say, hence the loudness button on a few consumer amps. Why not eq the sound "when needed", rather than add harmonics all the time?. Adding harmonics to possible problems elsewhere doesn't sound too clever an idea to me, two wrongs don't make a right, perhaps...(although you must understand, low-level listening will never have "impact", it's probably ok to "eq-up" the sound in such circumstances, as the sound levels bare little resemblance to reality)

Colouration can be pleasant, it's a fair comment. But the "exact same" colouration is not pleasant at differing levels, hence why it's probably best to go low distortion and eq your heart out, if any resemblance to the source doesn't feature highly on your wantslist...

 

[rnrss]

If the power of the amplifier is too high, the sound will be congested.
does anyone has simple schematic diagram for power amp with I think 30-60 watts

Do you mean compressed or nonlinear gain?

Which amp have you found to do that?

Here is one of several schematics I posted for you, just click on the link below:
http://sound.westhost.com/project19.htm

I doubt you will find anything much simpler for that kind of power...

 

[rnrss]

Are you sure it's low distortion amps that cause this?. I'd be more inclined to think it's probably the source and/or speakers, followed by components to a lesser degree.

Of course the impact will be lost at volumes less than "life like", pretty inevitable i'd say, hence the loudness button on a few consumer amps. Why not eq the sound "when needed", rather than add harmonics all the time?. Adding harmonics to possible problems elsewhere doesn't sound too clever an idea to me, two wrongs don't make a right, perhaps...(although you must understand, low-level listening will never have "impact", it's probably ok to "eq-up" the sound in such circumstances, as the sound levels bare little resemblance to reality)

Colouration can be pleasant, it's a fair comment. But the "exact same" colouration is not pleasant at differing levels, hence why it's probably best to go low distortion and eq your heart out, if any resemblance to the source doesn't feature highly on your wantslist...

well said Derf

 

[mpmarino]

Well if the money is an issue, and if you cant solder, and if a little setback is going to cause crushing disappointment, and financial ruin then you have no business building "anything" to begin with...

that's encouraging. let's get the newbies out (me included), and be left with 1 expert.

There are many people on this site who are very much in the dark in these and other areas as well and have no clu that a well designed class ab amp is spectrally cleaner than a class a amp and they still spout the class a jibber... tests have been done to prove this... but that doesnt matter because they have feedback... LOL when ya want more sales create a mystery and solving a problem that does not exist... the idiots will argue about for years...

I'm a glad idiot to get an education. Have you come here to bash the items we have been building and enjoying..and in a sly way, bash the inventor ?

No reason to bother building a 10 or 20 watt amp... Thankfully there are lots of very simple amps out here that have a very small parts count and they will give you substantially greater and better output than the amps this guy is pushing...

Hmm, when I look at the top of my screen, it reads ....>Pass Labs>...



If all posts MUST be kept to the subject at hand, then the only answer to the original posters question should be: build an Aleph 30 or an Aleph 60 or a scaled Aleph X to meet your exact power requirements...simple. no need for discussion of higher or lower power or non Pass amps.

-maybe all other references should be put over on the rnrss forum?

Now, this is usually an extraordinarily friendly place, but, now....

regards,
marc

 

[rnrss]

The only sad part is that this type of gear 'tends' to sound a little 'clinical'. Most often you wish it had a little more musicality, touching your senses, automatically making your body move, but.... they do make up with their big sound. Sometimes, certain parts of the spectrum sound larger than life in comparison to the finite boundaries of your listening environment.

Well I really have found very few "really" good recordings out there... but there are a few... I very much disagree with the term clinical that yo uused... I have built several low distortion systems and have never had one that sounded clinical.. by low distortion I mean a .15%amp... and the distortion I am talking about is not the distortion of the equipment as the biggest issue of coloration but the distortion of an amps inability to control a driver due to hi z regardless of the type or reason...

Now the systems I design always sound like one speaker that spans the distance between them and beyond and often the center image is considerable louder than the sides, often having an image so precise you would swear it was mono... a second point I am a stickler on is that the image must be linear up and down the scale... I hear the bass in the center as well as 1000 or 10000 etc... I am not satisfied until there is a nearly perfect center image...

Another thing I am a stickler on is equalization... I cant think of even one system that I have heard that the music sounds linear... There are always dropouts or at a minimum brown outs and my fav nasty ear splitting spikes... when I set up all instruments first have to sound brilliant and natural with the proper timber and sibilance and I must be able to hear the bass harmonics... then I must hear all music lets say linearly up and down the scale with the same brilliance... all note brilliant and no dropout or spikes... That is a requirement in anysetup I do...

If this is not done very accurately not only will your stereo be "off" and pull incorrectly to one side or the other but the center image will drop out and also pull incorrectly to one side othe other...

Turn the volume down and immediately the 'impact' is atleast slightly lost. In a nutshell they sound right from a given spl upward to another ceiling spl. Below that threshold they do not really touch your senses and above the threshold..... the reactions are different but everyone wants to reach out to the volume control and turn it down that bit.

Well they sound right for a given "range" of spl with a quality speaker using a high damping amp... Now I have 2 ranges for when I am in a really picky mood but most of the time I just listen to it at levels were eq'd at and above 110db and I use that eq often at 70 db as there is very little linear dropoff when sliding up and down the scale when going from very loud 110+db to 65 - 70 db... and that is a result again of quality speakers and a high df amp including very very low series resistance between the amp and the driver...

The loss that you are talking about that you hear is a combination of 2 things... and there are several possibilities that cause one of those things and the other is that your ear is not linear with volume... Fact is that your ear becomes flatter when the volume is 100db and up it is pretty flat already... now at 70 db for instance you will need to boost the bass and treble to make up for the deficiencies in the human ear... so when adding that to a low df amp the problem is additively worsened...

Secondly if you have a low damping amp you will notice that the sound is exactly as you said dull and clinical and also the bass will dropout considerably more when going from higher volume levels to the lower volume lower levels than with a high damping amp that delivers a df of 200 or greater at the speaker terminals.... I always shoot for 400 and now I am up over 2700 on a 4ohm load...

The really important point to note here is that I get the original artists harmonics with extreme damping, heny mancini for instance you would swear the horn is going to cave into it self the dynamics are so real to the live instrument... You know when they make a horn swauk it sounds like it is splattering...

So with this setup you will get very accurate bass and find yourself putting on headsets to check and see if it was really supposed to sound like that... Bass harmonics can sound really wierd sometimes... that is a huge difference than generating your own harmoncs with high series resistance, because though it may be have that warm color so does mine and I am playing the original uncolored program...

It is a mistake to think that the only way to get warm brilliant harmonics is to create your own... It just takes a little more practice setting up and a better understnding of what is "really" happening to the cone in your driver by comparison...

I know many out here scoff at the idea as tradition dies a slow death regarfless of its efficacy...

On the other hand, high distortion equipment do add much colouration to the original sound. Sometimes this colouration is not at all obvious; yes, they can be very pleasant. When done rightly, these type of equipment tend to sound right even at very low spls. And if combined with very sensitive speakers, they are revealing, dynamic and life like. And you can obtain concert levels in your listening environment.

Well they can be, since you qualified this with set up "rightly", they "can" sound dynamic at low volume level, but that does not change the fact that they are still very colored and you really are not hearing the original content... and the ear is more forgiving to any sound at lower volume levels also... Its the high volume levels that separates real qualities of a system in terms of distortion coloration... since you are in the biz you know that speakers tend to start coming unglued and all the nasties start to show up when pressures increase over 115db... Then you know spikes get spikier, booms get boomier and dips get deader...

IMaybe we are not talking about the same kind of high distortion here? Again I am not talking about amp internal circuit distortion it has to be up over 1% before it is really obvious...

High distortion equipment by itself is not the killer here... it is high z amps... High R wire... High R (series) crossover coil... series resistor, anything that reduces damping at the speaker terminals...

I am sure you must have had this happen to you since you are in the biz.... If you put a high z amp on a speaker and crank it up to 120 db you may hear the driver start to cut loose at some freq near its resonance if it is not perfectly tuned... Now replace that amp with a very low z amp and with a damping up to 10,000 then you will be able to crank 130 db out of that same speaker before it starts to cut loose... Now that is not to say high damping can only be heard at Loud volumes as I said above it really sounds great and dynamic at lower levels too as the speaker is being properly driven to its correct extension with very little compression due to Cms...

With either type of equipment, no one can reach concert level dynamic range even in the smallest of rooms!!

Really? Now I know you are pulling my leg a bit on that one...

You obviously never ran into community drivers where one driver will do 150db all day long...

I think I know what you are talking about and that will be my next project and most likely my final design...

You are talking about the sheer "amount" of air being moved as compared to a concert and that I would agree with... there is nothin sounds nicer than acdc with a 20foot long bass horn or aerosmith or the who with a total of 20foot high and 80foot long 15" stacks...
Yes the sheer volume of sound as in square yards of air being moved and that is what makes them sound so good compared to our square inches in our homes... every time they hit the bass it hits you in the face, now mine just tickles my nose but like horseshoes it close enough for my present purposes...

But as far as concert levels go in terms of loudness and dynamics I am getting 10 to 20 db between the valleys and peaks on the rta... so I dont see dynamics as an issue and as far as loudness is concerned I had this thing up as loud as 135db, now I know some concerts go considerably louder than that, but then you wons see me in the front row either... I go back till its about 110 - 115ish in loudness... If you do mean loudness I would think 135 db that makes the whole house heave like the begining of an earthquake would be considered concert level at least in my opinion... I hope this helps shed some light on why you are hearing what you hear with different amps and wiring configs...

 

[rnrss]

that's encouraging. let's get the newbies out (me included), and be left with 1 expert. /B]

No there will be several experts you just will not be one of them...

I'm a glad idiot to get an education. Have you come here to bash the items we have been building and enjoying..and in a sly way, bash the inventor?

Oh brother... You gotta be kidding me? I dont even know the guy I certainly have no reason to bash him, I am sure he is a great guy, but I admit there are a few people on here who truly deserve it... I have my own opinions and I back them up with real world experience... If you want to live in fantasy land, hey be my guest... You have lots of company... Just close your ears to anything I say and be very happy with whatever it is you are in love with ok... I am not in love with any amp, since I have 17 of them it shows I am a little slow at getting it right... I finally bought a new crown a few years ago and I will continue to buy them unless someone comes out with a better one... I am not inlove with my freaking amp... If you want to get up here and "SHOW" me these amps are better and I am all wet then be my guest and if you or anyone else can do a reasonable job of it then I will happily dump the crown and buy pass amp in a new york second... Do you know how fast a new york second is?

-maybe all other references should be put over on the rnrss forum?
regards,
marc

Good Idea marc.. we can call it the experts corner...

yeh regards to you too man

 

[planet10]

Some context for this thread can be seen here (the tread it was split from)

http://www.diyaudio.com/forums/showthread.php?s=&threadid=62095


dave

 

[rnrss]

Now thats the way to win a debate...

Simply edit out the competition....

I think its time for me to do an in depth write up on my website as my way of saying thank you....

 

[GRollins]

I seem to recall that somewhere in one of the rants above rnrss said that I designed the SOZ. Not so. Nelson Pass designed it.
135dB and acdc...I think it's clear where rnrss is coming from. Add an obsession with distortion specifications (never once addressing the fact that music isn't a steady sine wave and that distortion has dynamic components that are exacerbated by high levels of feedback) and it's pretty clear that his soi disant 'expertise' is based on a singe factor: loud.
There's a lot more to life than you image, rnrss. I started down the same road, back thirty years ago or so, but wised up. The old Cerwin Vega slogan "loud is beautiful as long as it's clean" used to cover all bets...or so I thought.
Fortunately, I learned differently.

Grey

P.S.: You might consider investing in a dictionary, rnrss. They're really quite cheap, you know.

 

[derf]

Who killed my post and for what reason?

I said nothing derogatory about Pass amplifiers, I just pointed out that I think if someone wants "a certain sound", I think they should try do it through eq/other means, rather than relying on an amp that creates new harmonics. If you use eq, you have a choice between a clean sound and another more "harmonious" sound. Surely this is a more flexible means to an end.

Infact, why did the other guys post go aswell, the one stating about musicality coming from the harmonics, what exactly did he do wrong?

Has freedom of speech gone out the window, does anything that doesn't align with *your*(whoever the deleter of posts is...) trend of thinking automatically get thrown in the sin bin?

 

[mpmarino]

Yep, mine is gone too. That's just fine with me. Most of my post was in response to comments that were irrelevant and absurd. I can't believe I actually took the time to respond to such garbage. The evidence of my lack of judgement is gone..GOOD! If it was done by a moderator..bravo! If it was a database problem..Thanks Bill (or Lunus?)!

now clicking on 'unsubscribe to this thread'

 

[derf]

Ah, it's been moved...

 

[destroyer X]

Ahahahah! good to have a shark in our beach

Hey guys, this one is mine!

regards,

Carlos

 

[GRollins]

Yes, it seems that parts of this thread have moved over to Solid State.

Grey

 

[GRollins]

Carlos,
Looks like you need a new razor, but I like the hair style.

Grey

 

[Variac]

Hey Grey He likes ALL Kinds of music:

acdc with a 20 foot long bass horn or aerosmith or the who

I remember an interview with a motorcycle mechanic in Citybike Magazine here in S.F.

He said " I've worked on every kind of motorcycle there is: Flatheads, shovel heads, pan heads......"