Depends on who made the tube amplifier... Old Hiwatt and Soldano have wide bandwidth Hi-Fi output transformers in them. Marshall and Fender on the other hand used cheapo wound output transformers that had limited bandwidth. Fender also used very small OTs in some of their amps. This limited bandwidth in their transformers.
I guess it depends on the company's design philosophy... Hiwatt and Soldano wanted to build very high grade amps while Marshall and Fender were more cost conscious. I'm sure there's other reasons involved but these reasons definitely played roles in each company's decisions. Either way, their decisions on OT quality/bandwidth played a role in the amp's sound.
I guess it depends on the company's design philosophy... Hiwatt and Soldano wanted to build very high grade amps while Marshall and Fender were more cost conscious. I'm sure there's other reasons involved but these reasons definitely played roles in each company's decisions. Either way, their decisions on OT quality/bandwidth played a role in the amp's sound.
It also depends on the desired product. Some of those amps are loud and clean by choice, others are guitar amps through and through.
Old Sunn amps used Dynaco transformers.
No reason you couldn't use a hifi transformer, but fidelity and wide flat bandwidth are not goals of guitar amps. Hifi amps SHOULD all sound alike, in that they should be faithful reproducers, adding nothing of their own. Contrast the guitar amp which is SUPPOSED to add its own coloration. The guitar amp is part of the instrument, not intended to faithfully reproduce anything. That is why guys say "I play a Marshall" or "I play a Fender." if you want to hear faithful reproduction of an electric guitar, plug it into the PA system.
That said, old AMpegs did go for hifi, Mr. Hull hated all that distortion and stuff. On the other hand his world was bass amplifiers.
The transformer is a factor, but there is a great story in the History of Marshall book. I think it was Ken Bran, one of Marshall's tech people. he had a set of Fender transformers. He decided to replace the Marshall transformers with the Fenders in one of their amps. Wanted to see how it sounded. He mentioned some subtle differences, but mainly he said, "It still sounds like a Marshall."
Old Sunn amps used Dynaco transformers.
No reason you couldn't use a hifi transformer, but fidelity and wide flat bandwidth are not goals of guitar amps. Hifi amps SHOULD all sound alike, in that they should be faithful reproducers, adding nothing of their own. Contrast the guitar amp which is SUPPOSED to add its own coloration. The guitar amp is part of the instrument, not intended to faithfully reproduce anything. That is why guys say "I play a Marshall" or "I play a Fender." if you want to hear faithful reproduction of an electric guitar, plug it into the PA system.
That said, old AMpegs did go for hifi, Mr. Hull hated all that distortion and stuff. On the other hand his world was bass amplifiers.
The transformer is a factor, but there is a great story in the History of Marshall book. I think it was Ken Bran, one of Marshall's tech people. he had a set of Fender transformers. He decided to replace the Marshall transformers with the Fenders in one of their amps. Wanted to see how it sounded. He mentioned some subtle differences, but mainly he said, "It still sounds like a Marshall."
Thanks for the responses. I was trying to figure out if most of the characteristic sound was in the amp circuit and the transformer just passed that through, or if the transformer itself contributed to the distortion. The Marshall anecdote seems to confirm some things for me.
But it really seems like you can use whatever you want depending on what sound you are going for.
But it really seems like you can use whatever you want depending on what sound you are going for.
As danFrank pointed out, many of the notable guitar amp builders over the last 65 years have used all manner of OT. No one will argue that Marshall amps suck because they use a cheap OT or that Mike Soldano’s SLO100 is über alles because it has a high cost OT. It all boils down to personal preference. If it sounds good, it is good.
My earlier post may have misled somewhat... I am in agreement with Enzo that the OT plays a role in amp's sound somewhat but not as large of an extent as the circuit components and topology; they play a much bigger role.
One of my pet peeves is a certain transformer manufacturer that is based in SoCal. If you believe their ridiculous marketing hype it seems to say that transformers ARE the end all be all for guitar amplifier tone. Of course they're in the business to sell transformers and unfortunately, they are not above exaggerating and distorting the truth to do so. And as an added bonus, their transformers are about twice the price of other transformer winders.
One of my pet peeves is a certain transformer manufacturer that is based in SoCal. If you believe their ridiculous marketing hype it seems to say that transformers ARE the end all be all for guitar amplifier tone. Of course they're in the business to sell transformers and unfortunately, they are not above exaggerating and distorting the truth to do so. And as an added bonus, their transformers are about twice the price of other transformer winders.
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The lowest note in a guitar with standard tuning is around 80 Hz. Most modern guitar speakers have little response above 5KHz. It would stand to reason that a guitar amplifier need not have the audiophile 20 Hz to 20 KHz frequency response, and many guitar amp makers exploited this fact to save money. The most "bang for the buck" cost saving opportunity in any tube amp is the OPT.
A modern HiFi OPT will use thin low loss laminations made with premium steel, and an interleaved winding technique to achieve wide bandwidth with low loss. The primary is wound in multiple sections which are interleaved with a multiple section secondary to achieve good coupling with minimum unwanted stray capacitance and leakage inductance. This "interleaving" costs time, which in the manufacturing world IS money.
I bought a large batch of surplus guitar amp OPT's nearly 20 years ago to make amps. They were made in the 80's by Schumaker, the same company that makes battery chargers. I took one apart to see how they are made. There is ZERO interleaving. One half-primary is wound on the cardboard bobbin, then the entire 0-4-8-16 secondary, then the other half primary is added with slightly thicker wire to make up for the longer winding length. The core and bobbin looks identical to the transformer in my Schumaker car battery charger from the same time period. The transformer spec stated 80VA from 80 Hz to 5KHz, 6600 ohms to 0-4-8-16 ohms. That was the only electrical information given, the rest of the single page sheet stated mechanical info.
So how much difference will this make in a guitar amp? Not much unless you try to play a bass guitar through a standard guitar OPT. Years ago I found that running a Bandmaster clone with several different OPT's made little difference in the sound at mid volume, and some subtle differences when cranked to 11.
A modern HiFi OPT will use thin low loss laminations made with premium steel, and an interleaved winding technique to achieve wide bandwidth with low loss. The primary is wound in multiple sections which are interleaved with a multiple section secondary to achieve good coupling with minimum unwanted stray capacitance and leakage inductance. This "interleaving" costs time, which in the manufacturing world IS money.
I bought a large batch of surplus guitar amp OPT's nearly 20 years ago to make amps. They were made in the 80's by Schumaker, the same company that makes battery chargers. I took one apart to see how they are made. There is ZERO interleaving. One half-primary is wound on the cardboard bobbin, then the entire 0-4-8-16 secondary, then the other half primary is added with slightly thicker wire to make up for the longer winding length. The core and bobbin looks identical to the transformer in my Schumaker car battery charger from the same time period. The transformer spec stated 80VA from 80 Hz to 5KHz, 6600 ohms to 0-4-8-16 ohms. That was the only electrical information given, the rest of the single page sheet stated mechanical info.
So how much difference will this make in a guitar amp? Not much unless you try to play a bass guitar through a standard guitar OPT. Years ago I found that running a Bandmaster clone with several different OPT's made little difference in the sound at mid volume, and some subtle differences when cranked to 11.
About 15 years ago, I remember getting a call from a buddy who lived in Arizona. He had won an estate auction that netted him, among other things, a barn with a stash of about three dozen guitar and bass amps...about a dozen combos and the rest were heads. Why does this sort of thing always turn up in someone’s barn? Anyway, I digress...the amps were primarily from the early 50s through the late 60s vintage-wise. There were the usual suspects in the Fender, Vox and Marshall pieces...Then there were a couple of Ampegs, a Gibson and the rest were Supros, Valcos, Silvertones a Gretsch, a Danelectro and a Kiesel (aka later as Carvin) branded lap steel amp. He called me as he had no idea what he had and he knew it. He figured that since I was a musician, mostly guitar and bass and I had learned to repair, mod and build amps that used valves (he’s originally from Edinburgh, Scotland) that I was an expert or at least I was more knowledgeable than anyone else he knew and trusted. Ok, my point to this...after some necessary, careful cleaning and vacuuming out of the interiors, some of these amps still fired up and functioned for the ten minutes I ran each or tried to run each through their paces. The primary issues were no-op Power tubes, dried out electrolytic filtration caps and shorted/blown/melted OPTs. With his permission, I did a “post mortem” on the dozen or so dead OPT and noticed that they went from a somewhat “primitive” materials and design aesthetic in the oldest, to a more refined and better material sensibilities by the early to mid ‘60s and the last 3, from what the resource guide he had told us were late ‘68 or early ‘69 DOM Fender amps...were “devolving” into crap. If I recall correctly, and I’m not 100% my memory is retrieving the recollections accurately here, 1 as out of a Twin Reverb, one was a Deluxe and the last came out of a Deluxe Reverb (it was a 4x10” combo...that ide remember). I reckoned that this was due to the legendary profits over quality era of crapola that Fender suffers after Leo sold the outfit to the CBS media conglomerate in ‘65. We loaded the whole mess up into his caged in flatbed trailer and took them back to his spread just north of Phoenix and unloaded the mess into his 30’ x 50’ shed/workshop where he renovated stuff that he bought at these kinds of affairs and sold in his wife’s antiques and oddities store out on Indian School Road (I think that was the street name). I showed him how to do basic trouble shooting and hooked him up with an acquaintance in Glendale, CA who then at 73 y.o. kept himself busy refurbishing these kinds of old amps and was a far better resource than I. I got to keep the one working Supro and an Ampeg B-15 fliptop That needed a new speaker (torn cone and melted voice coil), but the amp functioned fine when tested through a 2x10” cab he had at the shop. Again it was kinda of like a time capsule seeing how these OPTs “evolved” with the newfound demand and needs to handle relatively outrageous amounts of power and then went the other way with the accountants making engineering decisions at Fender. I’m no expert on OPTs and lamination designs or lack thereof, but I can tell you that the workmanship just looked shoddy and what seems solidly built in a ‘64 Showman was crap just five years later in an amp (the Twin Reverb) with approximately the same rated output using what looked like the same kind of quartet of 6L6 PTs in a classic AB push-pull design. The newer OPT windings reminded me of and had more in common with a scatter wound Humbucker pickup coil than a precision audio output transformer. Oh, I wind my own pickups too. Anyway, some of the bits inside the newer ones were reminiscent of a phenolic plastic like Bakelite, but the polymer was not really a phenolic...more like an ABS that got way too hot. I didn’t see any cardboard though. Just really shoddy compared to what was used 5 years previous and compared to what Marshall and Ampeg were using in the amps of contemporary manufacture in my buddy’s little treasure trove.
As an aside, as a contemporary gigging bassist, I really dig the newer Class D bass amps. No OPT...no Boat Anchor-weight heat sinks and yet they can deliver a righteous 800 watts RMS into a 4 ohm load. I have a GK like that, that fits into the compartment inside the hard shell case that my ‘78 MM Stingray rides around in and the amp weighs in at like 6 pounds, maybe. Now how about that kind of weight reduction in a bassist’s speaker cabs? I can always dream, right? lol
As an aside, as a contemporary gigging bassist, I really dig the newer Class D bass amps. No OPT...no Boat Anchor-weight heat sinks and yet they can deliver a righteous 800 watts RMS into a 4 ohm load. I have a GK like that, that fits into the compartment inside the hard shell case that my ‘78 MM Stingray rides around in and the amp weighs in at like 6 pounds, maybe. Now how about that kind of weight reduction in a bassist’s speaker cabs? I can always dream, right? lol
Mercury Magnetics:
"These are the one people talk about. They are great transformers but function and sound no better than Classic Tones, Heyboers or Hammonds. They also use more modern plastic bobbins so don't sound to my ear quite like the original transformers they mimic but this is only a very minor difference . At 3 to 5 times the price (largely because of all the advertising) it’s hard to justify using them. I personally dislike the advertising they use and mod kits they sell because they are misleading. The amp world is full of misinformation and I do my best not to support it. I only use Mercury Magnetics upon request or to replace a difficult to find transformer because Mercury has a really wide selection of odd ball vintage replacements that few others have. Some people believe they just have to have them but I'm not convinced there is a significant difference."
Despite the grammatical errors, this article makes some good points.
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I wonder if he would have given the same statement on sound quality without the knowledge regarding the bobbin material. Maybe he's got Golden Ears, though...
Does anyone really feel the need to add more to this?
Ooops?!?
Best regards!
that is real ????
As always, marketing, and confusing in an interested way make it easier for us to empty our pockets, in my beginnings, without internet and without knowledge (only the Philips Bible, the 5-20 on paper, a pair of English magazines and 1 French) Rake and junkyard materials (the component prices hiend!!! stores advertising in those magazines .........) They sold me at scrap price 2 Dynacord Eminent II, Prototype OPTs down the ground eager to see if they would ring, Incredible ! certainly the Italian Kit (magazine Nouva Elettronica) LX-1113 that just went on the market, it was **** !!!!! (70% its Chinese tubes, OPTs not much below Hammond for example and if I imagine that below others of unpronounceable price) .... I have already stopped dreaming of feeling some of the emotion of that sound, only with the kit LX-1113 "would have abandoned for disappointment" (and still cheap price compared to the cathedral of the exoteric, only half of the monthly salary each opt) Fisher 500C, Mk-IIIs, Bogen, .... and many more "crushed sonically "(many guitar amp transformers, true! direct to the trash). I was not able to make it sound bad neither in Parallel 6x EL34s double O getter mix. Mullard, Valvo, TFK, Haltron 6L6GC, Mullard EL37s (all bought at the rake price at that time) 6N1Ps without knowing the circuit, or more information than the visual to find pins "clean sound" .... now I know I played with a very high Raa (still not sure if 8 or 11K) and it is advantageous, logically bias fixed Class A (plus mix of nuts).
This reminds me what happened with BAT and 6H30, 6H30p-dr certainly sounds incredible in the Bijou Headamp, "70s decade!!!!!!", not without first accumulate garbage 6h30p-eb sowtec, thank goodness that I have not spent 1 cent in other brands dedicated to bathe gold pins, ..... I know it does not come to mind, In the Bijou Headamp triumph opinions in the forums with the 6DJ8 Bugle Boy, humbly my true jewels are those 6h30p of the 70s (I would not pay the $ 499 on ebay the last Once I looked at the price, but for that price I do not sell them either ............ sorry, I was just thinking about the keyboard.
As always, marketing, and confusing in an interested way make it easier for us to empty our pockets, in my beginnings, without internet and without knowledge (only the Philips Bible, the 5-20 on paper, a pair of English magazines and 1 French) Rake and junkyard materials (the component prices hiend!!! stores advertising in those magazines .........) They sold me at scrap price 2 Dynacord Eminent II, Prototype OPTs down the ground eager to see if they would ring, Incredible ! certainly the Italian Kit (magazine Nouva Elettronica) LX-1113 that just went on the market, it was **** !!!!! (70% its Chinese tubes, OPTs not much below Hammond for example and if I imagine that below others of unpronounceable price) .... I have already stopped dreaming of feeling some of the emotion of that sound, only with the kit LX-1113 "would have abandoned for disappointment" (and still cheap price compared to the cathedral of the exoteric, only half of the monthly salary each opt) Fisher 500C, Mk-IIIs, Bogen, .... and many more "crushed sonically "(many guitar amp transformers, true! direct to the trash). I was not able to make it sound bad neither in Parallel 6x EL34s double O getter mix. Mullard, Valvo, TFK, Haltron 6L6GC, Mullard EL37s (all bought at the rake price at that time) 6N1Ps without knowing the circuit, or more information than the visual to find pins "clean sound" .... now I know I played with a very high Raa (still not sure if 8 or 11K) and it is advantageous, logically bias fixed Class A (plus mix of nuts).
This reminds me what happened with BAT and 6H30, 6H30p-dr certainly sounds incredible in the Bijou Headamp, "70s decade!!!!!!", not without first accumulate garbage 6h30p-eb sowtec, thank goodness that I have not spent 1 cent in other brands dedicated to bathe gold pins, ..... I know it does not come to mind, In the Bijou Headamp triumph opinions in the forums with the 6DJ8 Bugle Boy, humbly my true jewels are those 6h30p of the 70s (I would not pay the $ 499 on ebay the last Once I looked at the price, but for that price I do not sell them either ............ sorry, I was just thinking about the keyboard.
Remember the Dynacord Eminent never was intended as a dedicated guitar amplifier, but as a microphone amp. OTOH, it's musical instrument contemporaries, such as Imperator etc., all used the same power amp circuitry, OPT's and PSU's, in particular one of two different options for two different output powers of 40 or 80 watts. These Dynacord OPT's nearly offer HiFi specs, and the Dynacord guitar amplifiers didn't give 'the' sound we all know from Marshall, Fender and the like.
Best regards!
Best regards!
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