the big paper v plastic OT debate

[jrfrond]

Just curious what were the sonic results at each step (i.e. how much of this sound change was affected by the caps, resistors, tubes).

Greg

Installation of NOS tubes made quite a bit of difference before anything else was changed. Transition to clipping was a lot smoother, and the tone was rounder, plus a better feel that wasn't QUITE there yet. The transition to carbon comps is what made another very palpable difference, and in combination with the NOS tubes, were responsible for the more vintage-like tone and feel. As far as the caps go, I really didn't hear much of a difference at all. However, I've seen a lot of those IC caps fail over the years, and this was a no-holds barred sonic and reliability upgrade, because you don't get second chances when something goes down during a Broadway show, especially one of that magnitude. I typically use Sozo in vintage restorations, because they are the closest to the old tubulars in terms of appearance and quality.

Ironically, when the show revamped, they chose to go with digital rigs and in-ears, and scrapped all of the tube amps (which included some chopped AC30's; I had to chop the Deluxes too, because the cabs went into iso-booths). I wouldn't mind having one of those for myself.

[MWJB]

Dai H wrote: "sort of like the PCB vs. point-to-point wired thing, where the buyer is supposed to draw an inference that one is better (or worse) than the other." The similarity lies in Enzo's earlier observation that you are not comparing 2 similar products with "just" the difference of bobbin material, or one being PCB with all the same components & layout as a handwired amp.

It's worth noting that so far, those who regard the bobbin issue as "snake oil" and many of those propogating the "snake oil" are saying exactly the same things!

RG says "Nylon versus cardboard/fiber/fish paper/etc. is a non-issue, **as long as everything else is the same**." & "But if you are out to make the cheapest possible transformer, you can (mis)use nylon bobbins to let you be sloppy with winding. And if you're out to be cheap, you probably load cheap, thick iron into the nylon bobbin and do not carefully pack and stack the laminations to make the gap small and consistent."

and similarly with the PCB vs handwired the issues are the same. In a "money no object" amp, if there is no difference between a high quality plastic bobbin item compared to the paper bobbin, if the builder is making a repro amp, it's a selling point...however mis-informed the customer, if this is on his wish list, it is the difference between you making a sale & not making a sale...if you are commercially building "money no object amps" you are probably counting every amp sold. So reality follows the myth (you think it's coincidence that Victorias come with RI Tung Sols & RI Jensens?)...BUT lets face reality, plastic bobbin OTs are typically found in mass market amps where ALL component costs are kept within tight margins.

Just like PCB vs handwired - the PCB amp typically share NO PARTS WHATSOEVER with the handwired version! I see a lot of tweed bassmans (apart from perhaps the chassis within reason, chickenheads & 1/4" RCA jacks) no other components
will be found on a Victoria, Kendrick, or Clark. In fact only 1 reproduction builder builds an amp that shares as much as 99% of circuit values as the RI. I have actually compared blueprinted handwired RIs, with PCB...there is a very subtle difference in tone...a very slight "fizz" or "rasp" compared to the slightly more open, natural handwired amp...& I mean very slight, not enough to keep you awake at night and you would have to have superhuman hearing to pick it out with the background of a band behind you. But then the PCB doesn't come with the same parts as the handwired version even if values & voltages, bias, tubes, speakers match as closely as can be reasonably expected...so I can't honestly say that even this small difference is purely down to being PCB vs handwired, it's just the case in this instance - with this PCB loaded with these parts. Looking at John's examples with the 5E3s, not all handwired 5E3s sound the same, even when using the same OTs.

I have also compared handwired RIs with similar circuit/voltage/bias/speakered repros...in one case, the best sounding amp literally followed the nicest pair of tubes, if we put them in the handwired RI & the second choice in the repro, then the RI sounded best, & vice versa. Note that we discovered this totally by accident, we weren't pushing for a forced choice preference on a certain pair of tubes, we just noticed the least amount of unpleasant artefacts in the sound with this pair. When I say "best sounding", I mean most natural, simply the sound with the least things wrong with it to my ear...which was irritating, as after hours of parts swapping, rebiasing, A/B listening tests the owner decided on fitting a pair of speakers that sounded to me like a box of spanners being shaken! ;-) Warmer, more vintage apparently?!

In the real world your PCB amp has a different layout, different caps, resistors, transformers & speakers compared to a high cost repro. Sometimes this is relevant, as with the poor layout on the often to be found oscillating PRRIs & PCB Marshal 1962s. So short story long, we have to work & base our experience with the actual amps and parts found in the real world amps. I genuinely don't doubt that plastic bobbin OTs & PCB can probably sound as good as the alternatives, if designed that way...but with that extra effort & costlier parts you eliminate the margin of cost between the mass market PCB offering and a 2nd tier handwired repro...so what's your USP, "it's PCB constructed with a plastic bobbin like a cheaper amp, it just costs 50% more!"...form an orderly queue, stop pushing at the back there....;-) All commercially successful small scale builder have a litle PT Barnum about them, not in a bad way necessarily, but because they have to. Would you buy a car from a guy on a forecourt who told you, "they're all really average, about the same, there's no reason to buy one of these compared to anything else"...we all live in a world with bills, mouths to feed, etc.

It's probably fairest to sum up my take on the situation as "many factors make A difference & very few amps sound THE SAME", I would be very relectant to agree that something "makes no difference" but to put the matter in a real world context & prove the point categorically is beyond the attention span & budget of most except the big manufacturers...and they already have thousands of units to sell & little motivation to prove the point either way.

Oooh, I've just remembered something I accused others of in another thread, "people come up with ever more elaborate ways of saying 'I don't know' "...I think I've just joined those ranks! :-o How embarassing!

[big_teee]

It does make an interesting debate.
What I really want to know is About the Snake Oil?
Everyone Compares everything to Snake Oil!
B_T

[cminor9]

It's worth noting that so far, those who regard the bobbin issue as "snake oil" and many of those propogating the "snake oil" are saying exactly the same things!

<snip>

It's probably fairest to sum up my take on the situation as "many factors make A difference & very few amps sound THE SAME", I would be very relectant to agree that something "makes no difference" but to put the matter in a real world context & prove the point categorically is beyond the attention span & budget of most except the big manufacturers...and they already have thousands of units to sell & little motivation to prove the point either way.

It's not a matter of whether a thing is beneficial in an absolute sense. The real question is, how beneficial is a thing in relation to all other factors? By that measure, aren't you are calling snake oil on paper bobbins?

[BeemerBoy]

Back when I was a student and during the years that I was a pro photographer I looks at photographs all day, every day. I read and owned a ton of photo books and had stacks of slides and transparencies and got to see a lot of other peoples work too. The result was that I developed me sense of sight to the point where I could discern very fine degrees of color balance and saturation that few other people (Who weren't photographers.) could match.

The result was that I could see imperfections in peoples photographic work that would drive me crazy but wouldnt bother anyone else. The adverage person couldnt detect what I saw as flaws and my criticisms of things that they couldnt see or that didn't bother them, only detracted from their joy ands satisfaction.

I think it's the same with some of these discussions concerning how and in what way amps reproduce or produce sound. The more experience someone has listening to nuances of electronic circuits, usually determines how developed their hearing process becomes and lets face it. some of you guys can hear things that the rest of us either cant hear or if we can hear it, doesn't matter. It comes down to this: A camera is worlds better than a Nikon but can you look at a slide taken with either one and tell me which was which? The fact is, you cant and under test conditions I usually cant either and THATS why, when I build an amp, I use whichever transformer comes in the kit or is specified by the designer. I expect the designers to come up with a satisfactory combination of parts that will fall within my price range.

I've also noyiced that in many cases, the boutique builders reproduce classic amps with parts so superior to the originals that sound comparisons are meaningless. Yes, they're the same circuits and so forth as the originals but the amps themselves are very different animals.

No, I don't expect you guys to agree with me but I did want to add a different perspective to the discussion that may appear to be about "the number of peas under the mattress" for many readers.

[MWJB]

I'm saying in an ideal world it might be snake oil, in the real world where typically cheaper, lower quality parts come with plastic bobbins, there is room for difference to exist and the difference between low & acceptable quality might be easily detected.

RG said "if everything else remains the same" then there is no difference, but that scenario does not typically exist.

If using paper bobbins is beneficial in giving customer peace of mind, irrespective of sonic benefit, a guy who wants to make the sale will advertise a paper bobbin...surely then, no one can be short changed if a comparable quality plastic bobbin OT can't sound any better or worse? The primary factors are therefore cost vs customer satisfaction & peace of mind.

I still "don't know".

[centervolume]

you arent alone. I am tracking the debate on may sites. We have all been perpetrated by sales information and I am after some hard information.

If the gap theory is correct, then if you get thinner plastic bobbins, we should be looking at a non issue.

But getting plastic that thin might drive up the manufacture costs... I cant think of any other applications for "paper-thin" plastic

[R.G.]

Sigh.

The bobbin material is a non-issue. Bobbin material has no more effect than wearing a black or white hat makes someone a good guy or bad guy; or wearing a white dress versus a red dress makes a woman innocent versus wild. Or a red-painted car faster than one which is painted powder-blue.

I really wish that the "Big Lie" technique were not so bloody effective on humans. Once it's started, no amount of reason or evidence will cure it. Pretty much all modern advertising and politics rely on it. The real bottom line is that almost no one will ever be convinced by evidence once they swallow the bait.

[cminor9]

no more effect than wearing a black or white hat makes someone a good guy or bad guy;

But but but... You've shattered my worldview!

[Enzo]

Snake oil is all well and good, but really, I think lizard oil is superior.

[R.G.]

...er, how about endangered salamander oil?

[Bruce / Mission Amps]

Here's my 2 cents...
I use custom wound trannys with paper bobbins and Kraft paper insulation because my customers want me to.
Also, quite a few years ago I noticed that, when doing transformer beta testing for a well know kit and speaker vendor, the Asian manufacturer started sending trannys out with two or three less laminations but the lamination stack was still the same dimensions... what's that mean?
Well, #1, they didn't think anyone would notice the actual laminations started getting thicker and the number of laminations started going down and down.
After pointing this out I was told I didn't know what I was talking about and they claimed there was no difference...
but you all just have to trust me, there was a tonal difference just after a few cycles of cost cutting like that.
They didn't work poorly or sound bad.... it's just that other for a few dollars more sounded better to me.
Of course some will say "no, can't be" or I have bat ears or some other nonsense but I turned my nose up at using them for those two reasons... cutting corners and saying I didn't know what I was talking about. Ha ha

[MWJB]

RG why the sigh? If there is "no difference", why bother with the effort of committing to type? Nobody's getting hurt, neither is better, or worse? They're all the same. ;-)

Why bother typing...

"If you use a nylon bobbin that restricts where you put the wires, or you use a nylon bobbin to let you scatter/random wind wires into the winding area, it makes a difference, but the material does not play in this game. It's where the wires are that matters. The magnetic field can't even see the bobbin material."

" Nylon bobbins can be used to lower the cost of winding. This does not have to be detrimental to winding quality at all, and can result in more space being available for wire, which has the possibility to make the transformer *better* than you can do with cardboard and fish paper, because you don't have to be so careful in stopping the wind 'way back from the edge of the bobbin."

Not doubting your wisdom on the matter, but earlier you seemed to suggest that there were indirect factors that could be associated with production that had a bearing, or even that plastic allows the potential for improvement? What am I misunderstanding.

[R.G.]

Why bother typing...

Because the proposition that [paper>nylon] is not only wrong, it leads you at right angles away from the truth, which is that neither paper nor nylon per se matters, and it helps obscure the things that do matter. It's the worst kind of pseudo-technical mysticism. It's worse for the person who wants to learn than no information at all because it is seemingly-plausible misinformation that directs them away from any real learning.

Not doubting your wisdom on the matter, but earlier you seemed to suggest that there were indirect factors that could be associated with production that had a bearing, or even that plastic allows the potential for improvement? What am I misunderstanding.

Let me see if I can be clearer. What matters is the relative positions of the wires inside the winding, not the stuff that spaces them apart. The magnetic field can't even tell that the insulation is there except that it forces the wires to be spaced out a bit. The insulation could be paper, plastic, laminated rice straw, hard rubber or whatever. As long as it does not let the voltages in the wires break over to adjoining wires, and is not itself magnetic or conductive, the M-field is unaffected.
[to the proofreaders: yes, this ignores secondary thermal, capacitive and RF effects; I'm trying to be simplistic for a point]

It is possible to make a sloppy, poor performing winding with either a nylon bobbin or a paper bobbin. Or a good one. The bobbin material does not matter. You can make a good or bad transformer on either one. But you do have to know what size wires to put in what relative position, and the bobbin material tells you **nothing** about that.

Presumably the original poster wanted some real information. It matters, and I bothered typing because there was some real information to be had. It can be said (and has!) that even if good transformers can be wound on nylon, but most are not, so therefore it is OK to make the blanket statement that "nylon =bad". What that does is to further hide the real information though.

This all reminds me a lot of the advertising in Futurama for "Batchelor Chow", and the secondary line "Now with FLAVOR!" or exhaustive medieval arguments about the number of angels which could dance on the head of a pin.

When someone presents me with a prominent exhortation in advertising that simply does not make any sense at all, it sets off the BS detector. Either the proud presenter knows that their stuff is nonsensical or not, and they either care whether they're right or not. That devolves into the famous four-squares chart.
=>"Don't know" and "care" means they are misguided and will feel bad when they find out the truth.
=>"Don't know and "don't care" means they are amorally in it for the money.
=>"Know" and "don't care" means that they are maliciously in it for the money and will attack you for spoiling their hunt.
=>"Know" and "care" is the group I personally prefer to buy from, but nonsense in the sales message means the seller isn't one of them.

[MWJB]

Thanks RG.

Ha ha, the 4 squares chart seems to overlook the "Know & care, but still trying to make sales/turnover in a competetive market" during a recession. I hear you on the Batchelor Chow, "New improved flavour" usually means "sales have slumped & we've had to take something (fat/sugar/salt) out, or add it in (fat/sugar/salt) to claw our way back into the market". If you have a commercial business, the objective is still to give people what they want & avoid going under, whether selling amps or Batchelor Chow.

FWIW the OT, assuming it's the part that came with the amp, is adequate & functions properly, is about the last thing I would change out for a value for money improvement in tone...actually, second to last before the PCB (after all the OT only needs 4-5 wires changing). The only other "real world" consideration I might have is if the OT has no end bells and is going to be a replacement in a valuable old amp & would therefore look out of place (& possibly affect resale) with a big plastic bobbin poking out.