Marshall transformers with paper bobbins vs. plastic bobbins

[jack daniels]

Excerpt from Classic Tone website:
http://www.classictone.net/PaperVsPlastic.html

"I have read and have been told by many knowledgeable and reliable sources within the amplifier industry that paper layer wound transformers (a.k.a. paper tube, paper bobbin, etc.) are better because they help provide an amplifier with that ultimate tone. They mention that the sound of amplifiers using paper layer wound constructed transformers from the vintage era of the 1950's and 1960's are preferable to modern era, nylon bobbin constructed transformers due to their outstanding tonal characteristics. Even though I am a little biased as President of Magnetic Components, Inc. and we still predominately manufacture our transformers using this fine, traditional, time honored method of winding our transformers, I must admit I was a little skeptical as well.

Well...after hearing the sound clips, I can now definitely say that amplifiers using paper layer wound transformers resoundingly sound better. In my opinion, our transformers in particular sound the best. Please don't take my word for it, hear why I think ours sound better."

Joe Janisch
President
ClassicTone By Magnetic Components, Inc.



JD- I used to own an old 50's tweed Fender Vibrolux 1x10" combo. Of course it could've been the vintage alnico Jensen and the sum of the parts thing but, I believe that the transformers were wound on paper bobbins and this is what contributed to the Vibrolux's great sound.

This got me to thinking about vintage Marshall amps, and had me wondering. When did Marshall's transformer suppliers (Radio Spares, Drake, and Dagnall) use the paper formers in their transformers, and for which particular Marshall amp models? Can anyone here who has an old vintage Marshall amp with the (paper former/transformers) verify this claim.

 

[Guitar-Rocker]

The original 18watt 1974 model, (circa 1965 to 1967), that came with the RadioSpares iron, was paper layer wound.

 

[m1989jmp]

I've never heard anyone that actually knows something about transformers mention bobbin material as a factor

 

[m1989jmp]

From a marketing point of view, it's completely understandable;

if someone makes an effort to reverse engineer and replicate a vintage OT, they'll probably include paper bobbin just for the sake of authenticity.

But to claim paper bobbins make or break an OT is complete nonsense.

 

[jack daniels]

Really? I've heard more than once from several sources including Classic Tone Transformers about positive observations heard when using paper vs. plastic for formers or bobbins in transformers. I'm guessing that the swap to plastic was more for consumer protection by not manufacturing a product that could become flammable (paper) if overheated.

 

[neikeel]

Most Drake and Dagnalls used by Marshall used card/paper/prespan as a former for their bobbins. The plastic ones you see came in during the 1980s.

Whether you attribute the tone to that material is matter for debate.

The wire, the lamination type is much more an issue, but if a manufacturer uses the old spec lams then they can reproduce the correct tone.

Old transformers used cheaper steel of lower spec and have, as a result, more impurities and, I believe, a more complex tone when an OT. PTs the difference is that the older spec trannies sag more when pushed to their limits.

I generally spec the old style bobbins for my amps but I am sure the plastic ones work just as well!

 

[jack daniels]

Referring to the example of my 50's Fender Tweed Vibrolux, it's really hard to tell in a vintage amp just how much a specific part or part(s) attribute to the overall sound. I do so love the classic vintage tones which is why I prefer old Fender amps and old Marshall amps. There was something magical about that tweed Vibrolux. How much the paper bobbin/former contributed to that sound I don't know but it was "the tone" to acquire.

 

[jack daniels]

Old transformers used cheaper steel of lower spec and have, as a result, more impurities and, I believe, a more complex tone when an OT. PTs the difference is that the older spec trannies sag more when pushed to their limits.

With regards to "quality of steel", I remember a TV show about the Titanic. In the show, quality of steel used in the early 1900's was discussed. The message conveyed was, that due to the extreme cold temperatures of the atlantic ocean and the high (sulphur?) content of early 1900's era steel (as well as some rivet issues) were all major contributing factors to the Titanic's sinking. The steel plates in the hull of the ship that struck the iceberg literally shattered like "glass".

Moral of the story, don't ever repurpose any vintage tranny laminates for ship hulls and then send them into the north atlantic. "This ship is unsinkable"

 

[BowerR64]

Why do transfromers have the end caps on them? I would think having them open would help the coils cool better then being enclosed

 

[neikeel]

Partial magnetic field shielding (see the big copper Q-band on the PT you showed).

Stop the windings being damaged during servicing.

Keep the 240vac on the PT primary protected

Keep the dust and muck getting inside.

Make them pretty and shiny-shiny

Er....any more?

 

[Adrian R]

Well all I can say is that both my amps are equipped with C/Tone P/Ts and Heyboer/Lydian O/Ts...both of which facilitate the usage of paper bobbins.

For my ears the difference is night and day compared to the original Dagnal units in which I believe use plastic bobbins.

With also the addition of a 3H choke...my amps sound ALLOT like the older Marshalls I use to own (2203/2204)..and better as the DSL can provide the player with far more clean gain and flexibility.

Better dynamics, better headroom, clearer, warmer, more articulate..and it now for sure has the original Marshall voice I grew up listening to.

The amp stock was great, but with these really three essential upgrades...most notably the transformers..and the amps TOTALLY rock.

 

[jack daniels]

Why do transfromers have the end caps on them? I would think having them open would help the coils cool better then being enclosed

I'm sure the end bells are used for RFI (and/or) EMI shielding. Whoops, I just noticed that Neikeel has this covered "teehee"

 

[jack daniels]

Well all I can say is that both my amps are equipped with C/Tone P/Ts and Heyboer/Lydian O/Ts...both of which facilitate the usage of paper bobbins.

For my ears the difference is night and day compared to the original Dagnal units in which I believe use plastic bobbins.

With also the addition of a 3H choke...my amps sound ALLOT like the older Marshalls I use to own (2203/2204)..and better as the DSL can provide the player with far more clean gain and flexibility.

Better dynamics, better headroom, clearer, warmer, more articulate..and it now for sure has the original Marshall voice I grew up listening to.

The amp stock was great, but with these really three essential upgrades...most notably the transformers..and the amps TOTALLY rock.

And there you go, there is a noticeable audible difference.

 

[Adrian R]

And there you go, there is a noticeable audible difference.

And JD, do you think it's merely coincidence that my amps now sound allot like the older amps that sported trannies with paper bobbins??

 

[paul-e-mann]

The cost of classic tone parts is so affordable, if you're capable of swapping them out yourself then it would be well worth the experiment to see if there's a difference. I don't think you can lose.

 

[neikeel]

And JD, do you think it's merely coincidence that my amps now sound allot like the older amps that sported trannies with paper bobbins??

The question is did you do other mods, exactly as the same time?
Can you prove (rather than the 'Placebo effect' of a nice shiny new transformer).
Don't get me wrong I tend to go with older style paper/presspan bobbin trannies, but I also want to be clear and scientific about making the claims
'

 

[m1989jmp]

Well all I can say is that both my amps are equipped with C/Tone P/Ts and Heyboer/Lydian O/Ts...both of which facilitate the usage of paper bobbins.

For my ears the difference is night and day compared to the original Dagnal units in which I believe use plastic bobbins.

With also the addition of a 3H choke...my amps sound ALLOT like the older Marshalls I use to own (2203/2204)..and better as the DSL can provide the player with far more clean gain and flexibility.

Better dynamics, better headroom, clearer, warmer, more articulate..and it now for sure has the original Marshall voice I grew up listening to.

The amp stock was great, but with these really three essential upgrades...most notably the transformers..and the amps TOTALLY rock.

Your DSL sound better now because you replaced inferior transformers (inferior winding, inferior materials) with Heyboers , not because Heyboers have paper bobbins...

Plus you added a choke, which alone contributes to few of the improved tonal characteristics.

 

[Adrian R]

The question is did you do other mods, exactly as the same time?
Can you prove (rather than the 'Placebo effect' of a nice shiny new transformer).
Don't get me wrong I tend to go with older style paper/presspan bobbin trannies, but I also want to be clear and scientific about making the claims
'

Hey neikeel... Actually the new trannies were sort of 'satin' finished if you will..nothing shinny about them..lol

I replaced the components out of one head first. I first replaced the O/T only because there was a member selling a Lydian model at a good price here. It was an easy install, and the price was right so it was like; 'what the hell...I then replaced the choke shortly thereafter because of it's ease of installation and low cost. I noticed an increase in performance.

But it didn't become really apparent until I brought my other head home from rehearsal for maintenance... Comparing them toe to toe it was very obvious. One head had better dynamics, clearer, warmer, and all around better fidelity characteristics. Funny thing is that at first I didn't put two and two together. I thought it must have been the tubes...so I swapped them completely. Nothing changed. The head that sounded better still sounded better... And then it dawned on me.. The head with the new components was the one that sounded better.

I then replaced the O/T and added a choke in the other head and then the gap was completely closed. Both heads, even with the different power tubes, sounded very similar...nearly impossible to differentiate.

I then replaced the P/Ts one at a time the following summer (last year) and again I noticed a disparity in tone..between the two heads and again the disparity vanished once both heads had the same components.

So, like, ah, no, there is no 'placebo effect', or snake oil, etc. dude...nothing but hard core fact.

 

[Adrian R]

Your DSL sound better now because you replaced inferior transformers (inferior winding, inferior materials) with Heyboers , not because Heyboers have paper bobbins...

Plus you added a choke, which alone contributes to few of the improved tonal characteristics.

Perhaps...Obviously more comparisons would have to be made between differing transformers, or more specifically, identical models sporting different bobbin material.