Guitaramp- and Hi-Fi transformers
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NewYorkDave
Well-known member
That's another one of those ridiculous generalizations that's become enshrined on the Internet.
Old Sunn guitar amps used Dynaco hi-fi output transformers; and if you've ever played one, "wimpy" is not the word you'd use to describe it!
Old Sunn guitar amps used Dynaco hi-fi output transformers; and if you've ever played one, "wimpy" is not the word you'd use to describe it!
walter
Well-known member
Some of the early silverfaced Fender twin and super reverbs used Ultra-linear output transformers. The primary has five wires instead of three, the screen grids are connected to the two "extra" wires. There is a resistor instead of a choke in the power supply, so the output tubes see the effects of a choke from the windings on the Ultra linear transformer, where the pre-amp gets a no choke supply. As I understand it, the choke delivers energy (when low notes and attack work the supply) to reduce sag. So with this setup the pre-amp could have some sag, while the power amp remains solid. Please correct me if I'm mistaken. From the many fender amps I have modded, the ones with ultra linear transformers ROCK.
G
Guest
Guest
I use 100W guitar transformers for 25W Hi-Fi, they have a good sectioned winding and good iron, though inductance is not enough for Hi-Fi on a full power. I believe, some 25W Hi-Fi transformers may be used for 100W guitar amps, however if they can keep with a voltage.
CJ
Well-known member
I have a EL 84 with Fischer Stereo output transformer.
Sounds better than the original Low Fi output iron.
Sounds so good I used to play a 1-4 progression for hours on end, just chords.
A to D. A to D.
Then maybe a few more hours of E to A. E to A.
You will know when you strike it rich with equipment. You will not be able to stop.
The early Fender Bassmans were using interleaved iron. Triad I believe.
Do the early Fender amps sound better?
Depends on what you play.
Keef and Brian did fine with the garbage gear, but then, they were more of a songwriting group.
Now they are more like a rock band, so sound is important.
And you can hear them live, nowdays, with these new sound systems.
So may as well put out good sound.
Remember, every note you play goes into outer space, and you cant get it back. So avoid contributing to interstellar noise pollution, and build a good amp.
:thumb:
Sounds better than the original Low Fi output iron.
Sounds so good I used to play a 1-4 progression for hours on end, just chords.
A to D. A to D.
Then maybe a few more hours of E to A. E to A.
You will know when you strike it rich with equipment. You will not be able to stop.
The early Fender Bassmans were using interleaved iron. Triad I believe.
Do the early Fender amps sound better?
Depends on what you play.
Keef and Brian did fine with the garbage gear, but then, they were more of a songwriting group.
Now they are more like a rock band, so sound is important.
And you can hear them live, nowdays, with these new sound systems.
So may as well put out good sound.
Remember, every note you play goes into outer space, and you cant get it back. So avoid contributing to interstellar noise pollution, and build a good amp.
:thumb:
skipwave
Well-known member
[quote author="RogerFoote"]One of them (a Sunn type 60W PP) has a massive choke and ultralinear connections at the Dynaco output transformer.[/quote]
I'm green with envy. :green: All my favorite guitarists play Sunn amps.
Which model did you follow? Mk IV?
I'm green with envy. :green: All my favorite guitarists play Sunn amps.
Which model did you follow? Mk IV?
something a little off topic. I know someone that was turning old PA and mono hifi amps into guitar amps many years ago I think I met them in 96 and they were doing this before then.
When they got a PA or mono hifi they would try it out to hear how the transformer sounded then the circuit stages would be changed to a fender type or marshall type or vox or a mix of types to "go with" the output transformer sound and the guitar and effects a player used.
I heard a couple of ultralinear ones they did. Ultralinear and guitar amps is interesting sometimes feedback sounded good sometime no feedback sounded good.
In the old Ampage days there were good posts about the lam stacking(how many Es and Is the same way)and M steel types used some liked M6 other M19 etc.
The thing I learned was to "go with" the transformer sound. I do this with microphone transformers
When they got a PA or mono hifi they would try it out to hear how the transformer sounded then the circuit stages would be changed to a fender type or marshall type or vox or a mix of types to "go with" the output transformer sound and the guitar and effects a player used.
I heard a couple of ultralinear ones they did. Ultralinear and guitar amps is interesting sometimes feedback sounded good sometime no feedback sounded good.
In the old Ampage days there were good posts about the lam stacking(how many Es and Is the same way)and M steel types used some liked M6 other M19 etc.
The thing I learned was to "go with" the transformer sound. I do this with microphone transformers
> Why do people say that a HiFi tranformer will sound wimpy for a guitaramp?
Because they are mixed up.
Good Hi-Fi iron can be "too clean" for tone production (as opposed to tone REproduction). Naked guitar strings sound thin. Bent bass-waves makes the sound richer.
Also, and more important: musicians have to move around a lot to make even a little money. For most musicians, cost and weight are VERY important. An undersized bent-bass transformer can play the gig just as well, with less strain on arm and wallet.
> Old Sunn guitar amps used Dynaco hi-fi output transformers
Yes, but pumping over 100 watts in iron that Dyna called "60 Watts". That's about the right derating. If iron is barely-clean at 10 Watts at 20Hz, and 60 Watts at 50Hz, then it will be barely-clean (not perfectly clean) at 100-120 Watts at 75Hz.
The (early) Sunns are very powerful, can be boomy for some styles and speakers, don't get the soft funky overload of cheaper/lighter amps. The Sunns are king of some work and beasts for other work.
My Traynor YBA-2 was rated 24W, makes 18W midrange at what I call "undistorted" (don't look badly bent on 'scope), but with a puny OT that I would not call 8W in good hi-fi duty. It is a great guitar amp, and an "excellent value for the money" bass amp. It does not pass the bottom octave of bass guitar, and even nicks the bottom notes of guitar, but the bending is "toneful" not harsh.
> I use 100W guitar transformers for 25W Hi-Fi
Sure. If it passes 100W at 82Hz acceptably, it'll pass 25 Watts at 41Hz just about the same. And on full-range music (unlike solo instrument amp), you just don't get FULL power at the lowest frequency, or not often enough to matter. Anyway typical speakers crap-out before decent iron. I do have a pipe-organ track with a brick on the 32Hz pipe for a full 27 seconds, and 32Hz sandy-state amps; but no speaker which will reproduce what I heard in the room. (Interestingly, my car speakers almost do justice, but only with the windows rolled up tight.)
Use Hi-Fi iron if you wish. If the cost and weight makes you gasp, use hi-fi iron rated much less than your tubes. Budget push-pull hi-fi iron should sound fine with guitar at twice the hi-fi rating. Great p-p hi-fi iron might handle 4X the rated hi-fi power, though I'd be a bit concerned about the B+ (and winding-core voltage stress) being about twice the value the designer assumed.
Single-ended iron tends to be a bit of a compromise in any case. But all SE amps end up being a balance between heat, cost, weight, cost, bass, cost, and output. And some really great gitar licks have been played on under-ironed and under-tubed SE practice amps.
> get the SE 6L6 / One Electron combo
That's sure over-weight and over-budget!
Hammond 125ESE should be more than ample for 6L6 and guitar at 8 Watts. I think you save 8 pounds and $50. 125ESE and 6550 will "do" 16 Watts, though the lowest guitar notes will be strongly iron-flavored. I'm dreaming of a One Electron SE with a 813 for just about 37 Watts SE, but it will make a Fender Twin feel like a lightweight.
> early silverfaced Fender twin and super reverbs used Ultra-linear output transformers
I thought it was some of the later, bigger, Fenders. But whatever, yes, UL has been done.
I don't think any UL guitar amp became a Real Classic. They are very clean up to a point, and then distort. Not quite as abruptly as a transistor amp, but the sand amp will be a lot lighter, even at the excessive power levels some of the later Fender UL amps were doing (160 Watts from one pair of bottles). Some modern techs un-do the UL connections to go back to a more "raw" pentode sound.
> It's bass heavy as is
Be sure it isn't just shy on treble. Most guitar wants everything over 2KHz about 6dB higher than everything below 1KHz. If you don't have that top-boost, it's dull.
> every note you play goes into outer space
Send more Chuck Berry!
Because they are mixed up.
Good Hi-Fi iron can be "too clean" for tone production (as opposed to tone REproduction). Naked guitar strings sound thin. Bent bass-waves makes the sound richer.
Also, and more important: musicians have to move around a lot to make even a little money. For most musicians, cost and weight are VERY important. An undersized bent-bass transformer can play the gig just as well, with less strain on arm and wallet.
> Old Sunn guitar amps used Dynaco hi-fi output transformers
Yes, but pumping over 100 watts in iron that Dyna called "60 Watts". That's about the right derating. If iron is barely-clean at 10 Watts at 20Hz, and 60 Watts at 50Hz, then it will be barely-clean (not perfectly clean) at 100-120 Watts at 75Hz.
The (early) Sunns are very powerful, can be boomy for some styles and speakers, don't get the soft funky overload of cheaper/lighter amps. The Sunns are king of some work and beasts for other work.
My Traynor YBA-2 was rated 24W, makes 18W midrange at what I call "undistorted" (don't look badly bent on 'scope), but with a puny OT that I would not call 8W in good hi-fi duty. It is a great guitar amp, and an "excellent value for the money" bass amp. It does not pass the bottom octave of bass guitar, and even nicks the bottom notes of guitar, but the bending is "toneful" not harsh.
> I use 100W guitar transformers for 25W Hi-Fi
Sure. If it passes 100W at 82Hz acceptably, it'll pass 25 Watts at 41Hz just about the same. And on full-range music (unlike solo instrument amp), you just don't get FULL power at the lowest frequency, or not often enough to matter. Anyway typical speakers crap-out before decent iron. I do have a pipe-organ track with a brick on the 32Hz pipe for a full 27 seconds, and 32Hz sandy-state amps; but no speaker which will reproduce what I heard in the room. (Interestingly, my car speakers almost do justice, but only with the windows rolled up tight.)
Use Hi-Fi iron if you wish. If the cost and weight makes you gasp, use hi-fi iron rated much less than your tubes. Budget push-pull hi-fi iron should sound fine with guitar at twice the hi-fi rating. Great p-p hi-fi iron might handle 4X the rated hi-fi power, though I'd be a bit concerned about the B+ (and winding-core voltage stress) being about twice the value the designer assumed.
Single-ended iron tends to be a bit of a compromise in any case. But all SE amps end up being a balance between heat, cost, weight, cost, bass, cost, and output. And some really great gitar licks have been played on under-ironed and under-tubed SE practice amps.
> get the SE 6L6 / One Electron combo
That's sure over-weight and over-budget!
Hammond 125ESE should be more than ample for 6L6 and guitar at 8 Watts. I think you save 8 pounds and $50. 125ESE and 6550 will "do" 16 Watts, though the lowest guitar notes will be strongly iron-flavored. I'm dreaming of a One Electron SE with a 813 for just about 37 Watts SE, but it will make a Fender Twin feel like a lightweight.
> early silverfaced Fender twin and super reverbs used Ultra-linear output transformers
I thought it was some of the later, bigger, Fenders. But whatever, yes, UL has been done.
I don't think any UL guitar amp became a Real Classic. They are very clean up to a point, and then distort. Not quite as abruptly as a transistor amp, but the sand amp will be a lot lighter, even at the excessive power levels some of the later Fender UL amps were doing (160 Watts from one pair of bottles). Some modern techs un-do the UL connections to go back to a more "raw" pentode sound.
> It's bass heavy as is
Be sure it isn't just shy on treble. Most guitar wants everything over 2KHz about 6dB higher than everything below 1KHz. If you don't have that top-boost, it's dull.
> every note you play goes into outer space
Send more Chuck Berry!
Thanks, PRR..!
G
Guest
Guest
[quote author="RogerFoote"]
Btw, the MK IV output is rated at 60/120W... Kins of an odd rating, what is that about?[/quote]
They have a funny switch in the speaker jack. When you use one speaker, it works on 8 Ohm/60W, when you connect both it switches output transformer's tap to 4 Ohm.
Btw, the MK IV output is rated at 60/120W... Kins of an odd rating, what is that about?[/quote]
They have a funny switch in the speaker jack. When you use one speaker, it works on 8 Ohm/60W, when you connect both it switches output transformer's tap to 4 Ohm.
> the MK IV output is rated at 60/120W...
In Dyna literature?
There are two limits: heat and saturation.
Heat is just never an issue in push-pull audio iron. For other reasons, the iron tends to be physically large for the power, and no listenable audio stays at full power for long. However heat is due to resistance loss. And audio power is expensive. So this resistance loss and resulting power loss may be annoying.
Saturation is proportional to V/F. For any given lowest frequency, there is a maximum voltage it can handle "cleanly". "How clean is clean?" is a grey-zone; distortion does not rise all that abruptly, not like clipping.
So the -same- transformer, sane frequency, same/similar THD, can be worked as 4K:8 at 50 watts or 2K:4 at 100 Watts. Both conditions imply 447Vrms across the primary, 20Vrms across the secondary. The iron will saturate about the same.
Note also that this is a nice fit to the case where you make two models with power supply voltage about the same (perhaps limited by standard filter caps) but fit the higher-price model with four tubes instead of two. The audio voltage stays the same. For same load, power would be very nearly the same; but half-load gives double power, yet you only stock one model of iron.
The resistance loss might be, say, 1 ohm as seen from the secondary. With 8 ohm load that's about 12% loss, With 4 ohm load it is about 20% loss. So working at same-voltage and half impedance "to get double power" will give you less than twice the power. It might be accurate to say 50 Watts and 90 Watts. The difference is smaller on iron aimed at 82hz, because the low inductance and loose THD requirements allow very low winding resistance, often much less than 1 ohm on the speaker side. And geetar amp power specs are always rounded-up, and never really say how it "sounds".
In Dyna literature?
There are two limits: heat and saturation.
Heat is just never an issue in push-pull audio iron. For other reasons, the iron tends to be physically large for the power, and no listenable audio stays at full power for long. However heat is due to resistance loss. And audio power is expensive. So this resistance loss and resulting power loss may be annoying.
Saturation is proportional to V/F. For any given lowest frequency, there is a maximum voltage it can handle "cleanly". "How clean is clean?" is a grey-zone; distortion does not rise all that abruptly, not like clipping.
So the -same- transformer, sane frequency, same/similar THD, can be worked as 4K:8 at 50 watts or 2K:4 at 100 Watts. Both conditions imply 447Vrms across the primary, 20Vrms across the secondary. The iron will saturate about the same.
Note also that this is a nice fit to the case where you make two models with power supply voltage about the same (perhaps limited by standard filter caps) but fit the higher-price model with four tubes instead of two. The audio voltage stays the same. For same load, power would be very nearly the same; but half-load gives double power, yet you only stock one model of iron.
The resistance loss might be, say, 1 ohm as seen from the secondary. With 8 ohm load that's about 12% loss, With 4 ohm load it is about 20% loss. So working at same-voltage and half impedance "to get double power" will give you less than twice the power. It might be accurate to say 50 Watts and 90 Watts. The difference is smaller on iron aimed at 82hz, because the low inductance and loose THD requirements allow very low winding resistance, often much less than 1 ohm on the speaker side. And geetar amp power specs are always rounded-up, and never really say how it "sounds".
CJ
Well-known member
Core size is the bottom, but coil geometry is the top.
So with hi-fi, you have two things being adjusted.
I turn down the bass all the way, so all I care about in the Hi-Fi trans is the the upper end.
Bigger core = better bass but more capacitance, so less high end, unless treated. Compromise city.
Extended range xfmr might tweak feedback harmonics, try it and see.
I would not go out and buy a hi fi trans just to see the difference, but if you happen to have an old tube carcass laying around with some Mac iron, WTH?
I never did like those Dumble amps, too heavy, and too clean.
But if it does not break, nite after nite, that is worth a tone trade off, I guess.
For you Newbies, a space satellite has a recording of Chuck Berry's Johnny B Good on board, if your wondering about the PRR ref.
Launched back in 68? 73?
68 to 73 cannot be held accountable .
So with hi-fi, you have two things being adjusted.
I turn down the bass all the way, so all I care about in the Hi-Fi trans is the the upper end.
Bigger core = better bass but more capacitance, so less high end, unless treated. Compromise city.
Extended range xfmr might tweak feedback harmonics, try it and see.
I would not go out and buy a hi fi trans just to see the difference, but if you happen to have an old tube carcass laying around with some Mac iron, WTH?
I never did like those Dumble amps, too heavy, and too clean.
But if it does not break, nite after nite, that is worth a tone trade off, I guess.
For you Newbies, a space satellite has a recording of Chuck Berry's Johnny B Good on board, if your wondering about the PRR ref.
Launched back in 68? 73?
68 to 73 cannot be held accountable .
