Vintage mojo... What is it exactly?

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Better metallurgy, tighter machining, better chemicals in the caps and resistors (worse for your health) more attention to detail, better quality control. Every single part of this old gear down to the molecular level is made to a much higher quality. It all adds up.
 
Better metallurgy, tighter machining, better chemicals in the caps and resistors (worse for your health) more attention to detail, better quality control. Every single part of this old gear down to the molecular level is made to a much higher quality. It all adds up.
Things aren't what they used to be...
70 years of continuous R&D resulting in poorer products. It's time to stop. Ditch the LED, let's grab the kerosene lamp. :cool:
 
Difficult to explain what is mojo or magic, but I think that using the stuff you like is something that have no explanation at all. Could be a combination of objective data and subjective opinions but, at last, what is really important is to be able to decide which equipment to use to achieve good results.
 
Better metallurgy, tighter machining, better chemicals in the caps and resistors (worse for your health) more attention to detail, better quality control. Every single part of this old gear down to the molecular level is made to a much higher quality. It all adds up.

I'd agree with you on everything besides better metallurgy. In my experience, most electro-mechanical things (and also mechano-acoustic things) from the past which have more "mojo" have it because of technically "poorer" and less pure metallurgy.
 
Samuel Pepys Sir :)
I'd think that the greater differences between the Flea 49 vs a well maintained old Neumann M49 could probably be put down to the capsules used. Followed secondly, and further down the spectrum, by the different output transformers and the valves.

Do you know what capsule was installed in the Neumann m49's that you've used and liked?
I don't know what percentage of M49's used the M7 capsule, but all of the ones I personally liked had K47 capsules. Whether that was as originally installed, or it was a replacement somewhere down the line I also don't know.

Of course the Flea uses a copy of an old M7.



The other factor would have been the head basket shape, but the Flea is about as close to the Neumann as you're going to get in that respect.
 
I don't personally think there's any mystery behind whatever "mojo" there might be in a simple 3 transistor gain stage as used in a Neve.

Firstly, take away the input transformer, and replace the tantalum coupling caps with components that have a lower distortion dielectric. A Neve now won't measure and sound the same as it did before.

Onto the little amp itself: We don't have a diff input pair so there is no cancellation of H2 due to the curved exponential of V in/I out. And while there is a "fair" amount of open loop gain before we wrap feedback around it to get our circa 25dB per stage, there's not a huge amount since it uses simple resistive loads on the collectors (and the emitter output) so there is still some gradual increasing of distortion products as the signal approaches the 24V rail.

This in contrast to a typical op-amp which might use active loads (current mirrors to balance diff pair, current sources/sinks etc.) which will lower distortion and also keep the signal clean and free of distortions right up until signal hits the rails. SPLATT!

Further down the list of items that "help" the mojo in our little amp are such things as a lack of any beta enhancing technique for the 2nd stage etc., etc. Reductio ad finem.

Edit - P.S.: When Rupert Neve, Mike Bachelor, Dick Swettenham et al. were designing these simple gain stages, they were coming from a world of vacuum tubes so the early solid state topologies they designed were quite similar to how it'd been done in their older valve designs.
Transistors were initially also relatively expensive so economy of use was important.

P.P.S. Having circa 80mA of DC current through the primary of the output transformer is also part of the early Neve mojo of course.
 
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Things aren't what they used to be...
70 years of continuous R&D resulting in poorer products. It's time to stop. Ditch the LED, let's grab the kerosene lamp. :cool:
70 years of engineering better power consumption and and cheaper manufacturing. And yes, visual quality is slightly better with kerosene. I have used a vintage u47 and the metal is undeniably better.
 
Better metallurgy, tighter machining, better chemicals in the caps and resistors (worse for your health) more attention to detail, better quality control. Every single part of this old gear down to the molecular level is made to a much higher quality. It all adds up.
I don't agree. All parts used in nowadays circuits are objectively better. Although I do agree on that the result is not necessarily a better sound. In my opinion the 'mojo' boils down to realizing that there was a lot of pleasant sounding elements in the far less 'optimal' signal chains from the past. 'Vintage mojo... What is it exactly?' could be the wrong question as it implies that there is one answer only. If you start looking at individual pieces of gear you might be able to figure out why that design sounds good.
 
It seems to come down to cost cutting and optimisation vs refined manufacturing tolerances and understanding.

It often doesn't impact the sound but it really does have an impact on the longevity of a product.
One good example of this is the Fender Super Reverb; I own a 1964 model and I have tried several of the modern reissues of the same thing. the reissues are different sounding, this could be down to the speakers being "burnt in" after nearly 60 years of use or numerous other differences in the design, the key difference is the use of a pcb against hand wiring.

I suspect though that any heavily gigged reissue will be long dead in 56 years time, pcb's are much less robust (I have seen many dead- beyond economic repair pcb based amps) and one serious crack will render the amp useless but I reckon mine will still be going strong.
So that is one objective example of the progress in manufacturing resulting in a poorer quality product

It could certainly be argued that the amount of conductive material the signal has to travel down is significantly reduced on the pcb model (cheaper and of course better for the planet) and therefore should sound worse.... there must be something like 100 times more conductive material in the vintage amp.
Of course if there is enough conductive material, then there is enough and it shouldn't sound different but that is just one of the hundreds if not thousands of differences between the two products that could have an impact on the sound.
 
It could certainly be argued that the amount of conductive material the signal has to travel down is significantly reduced on the pcb model (cheaper and of course better for the planet) and therefore should sound worse.... there must be something like 100 times more conductive material in the vintage amp.
Of course if there is enough conductive material, then there is enough and it shouldn't sound different but that is just one of the hundreds if not thousands of differences between the two products that could have an impact on the sound.
Regarding the low-current parts of a tube amp, conductivity is a negligible factor, but stray capacitance is important. There are enough examples of a classic circuit which, after being transferred to PCB, exhibit oscillations and frequency response aberrations; rather than re-lay the PCB, very often a band-aid was applied in the form of grid resistors and HF leak capacitors. Combining with different vendors for transformers, different tube manufacture, loudspeakers using new materials and glues, and whatnot, you end up with a significantly different beast.
 
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I have a 249 I got back in the 80s with AC701. It is a great mic that stands the test of time. Great on vocals and anything acoustic, however 2 things is the polar pattern is very wide even in cardioid and therefore shows the room acoustics which can be detrimental to the recording when in questionable rooms. Second VO talent have mentioned the noisefloor is noticeable. when used in a spot with music and FX you don’t notice it but voice on its own is noticeable.

The compression sound you talk about is an interesting quality.
I recently bought a Violet Design Globe Pre with the VIN 26 bayonet capsule. I want to also get the U67 capsule for it or another one. I love the sound of this microphone. It’s a SS FET preamp but does not have that over bright tone of most modern mics. I put it on my C7 Yamaha and noticed that slightly compressed sound field when its close up on the piano. It captures what my ears hear when I put my head in the same location. For a more natural sound , you pull the mic back from the piano and capture more room to locate the piano in a space.
These are made in Latvia and I recommend them for a more modern mic that has the original M7 sound.
 
It seems to ...

It often doesn't ...

I suspect ...

It could certainly ...
Hedge a little?

Speakers from an amp like a Fender have a pretty wonky frequency response to begin with so you're not really going to hear much of a difference even after 60 years. Heck you can have a few small tears in the cones and they still won't sound different.

Handwiring vs PCB doesn't matter at all. What does matter is implementation. If the manufacturer knows what they're doing, they can make a PCB version that will work exactly the same and be highly reliable. Unfortunately many manufacturers don't really take the time and care to implement things properly and the techniques are a little different because tube circuits with very high impedances and heaters and high voltages present different challenges. But I think I would trust Fender to do it correctly (although I wouldn't be shocked if they didn't).

The "amount of conductive material" should not matter at all. The old solid core cloth covered wire is thick enough that I don't think inductance would be in play (although current travels on the surface much more than in the core so not being stranded might impact inductance). But the inductance will be so small it will have no effect on anything at audio frequencies.

What could be a little different are transformers. When pushed transformers might sound a little different at LF. But again, that's all in the implementation.
 
I have a 249 I got back in the 80s with AC701. It is a great mic that stands the test of time. Great on vocals and anything acoustic, however 2 things is the polar pattern is very wide even in cardioid and therefore shows the room acoustics which can be detrimental to the recording when in questionable rooms. Second VO talent have mentioned the noisefloor is noticeable. when used in a spot with music and FX you don’t notice it but voice on its own is noticeable.
I would attribute both problems to dirty capsules.
 
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Here’s my hot take-
The engineers creating the first microphones in the 1870’s (Bell, Berliner, Edison) were on the absolute bleeding edge of technology. Bell paid Berliner a million bucks for the rights to his carbon button mic with objectively horrid frequency response, with noise and distortion figures that would make your AP laugh at you. At the time, they were so impressed, driving around in horse drawn carriages, that they could understand what someone was saying over a wire a ways away, they called it a success. For the time, it was!

Time goes by, technology improves. Eventually broadcast radio technology shows up and maybe these carbon mics aren’t cutting it. What can we do? We’ll throw the best technology of the day at it try and engineer something that’s an improvement. Lower noise, wider frequency response, lower distortion, maybe change patterns, etc. Maybe we’re still limited in just how much better we can make it at that time, and also an engineering spec that doesn’t really care about response over 10kHz cause radio broadcast doesn’t have the bandwidth and speakers can’t really reproduce those frequencies. Hell, until around WW2, most of the world was using DC bias on tape machines. Incredible! Portable sound studios! Not that AC bias hadn’t been invented and shelved a few times already…

This continues until an outright explosion of music making and technology really helps deliver full fidelity recording and playback to the masses. We look at the mics again and realize well the distortion is so high because we’re overloading the mic which we designed back when it was still 30 feet from an orchestra/ensemble. So back to the drawing board, and with whatever spec they were working with, a little lower noise, wider frequency response, lower distortion. Reproduction equipment enters the home! Speakers get better, now we can hear all the noise from tape and mics. FM broadcast lets us hear above 10kHz!

They have, however, arrived at a point where they have enough of a command over the technology that they also can subjectively ‘voice’ a microphone to sound more or less the way they wanted. Only world class studios own these tools, mind you. That’s where the majority of popular music is recorded before the proliferation of far less expensive transistor technology, etc.

This continues until the modern era, with engineers chasing specs resorting to rectangular capsules to avoid capsule resonance, RF bias, losing the transformers (they’re expensive! high distortion! Reduced bandwidth! Heavy!)

All the while, music is changing as well. Eventually we’re letting computers make sounds. Early on, they’re not giving us response past 12kHz, so maybe that’s as far up as the EQ on the console needs to go. EQs and compressors are inexpensive enough to put on every channel of a mixing console. This changes the way we make records, changes the very sound of records.

Fast forward to the modern era. There’s technologically nothing holding us back from smoking every last one of those engineering specs from days past. The humble MacBook Pro has a three microphone array of $0.25 electret capsules and a shit ton of DSP that can pick your voice out of a noisy room. And if someone blindly played you a vocal recording through it, nobody would be able to tell you it wasn’t at least a mid-grade condenser mic. (Don’t tell the space cadets.) A 251 it’s not, but that’s beside the point. My grandmother doesn’t have to go to Abbey Road to sing backing harmonies on my album any more.

Any of us can look back and subjectively say ‘that’s when music sounded the best’ and then all one needs to do is study the technology of the day -very- carefully to determine what exactly was contributing to the sound. That amounts to an entire system. What kind of resistors, what kind of wire, was the transformer winder counter a little off? Were the steel laminations somehow really great in the 60’s? Some dust and spit on the capsule?

One man’s mojo is another man’s non-starter.

I’d argue that Flea may be voicing their m49 mics to grab a ballpark representation of a vintage unit but minus the decades of component aging and patina. It might be hard to sell a subjectively ‘dark’ mic with a shit ton of compression designed to be 20’ from an orchestra in 2021, be it a 100% identical circuit repro or not. Is that capsule tensioned up the same? Did the original m49 diaphragm stretch out a bit? Do they have a carbon comp plate resistor adding second harmonic distortion? Are tubes the same as 60 years ago?
Hell, Flea might have based their mic on a particular unit that sounded good to them. What I love to see is, “it’s exactly the same, we just lowered the noise and gave it extra headroom”

Sorry if that was a long winded waste of time.
 
Regarding the low-current parts of a tube amp, conductivity is a negligible factor, but stray capacitance is important. There are enough examples of a classic circuit which, after being transferred to PCB, exhibit oscillations and frequency response aberrations; rather than re-lay the PCB, very often a band-aid was applied in the form of grid resistors and HF leak capacitors. Combining with different vendors for transformers, different tube manufacture, loudspeakers using new materials and glues, and whatnot, you end up with a significantly different beast.
I am not a tube guy but I used to spend time with Peavey's top guitar amp designer (5150, etc). From observation it appears that lead dress for point to point wired amps, or PCB layout can dramatically impact the sound character of high gain amp stages. The benefit of PCB amp layouts is that they will be completely repeatable, for better and worse. Crosstalk and signal leakage is part of that sound character.

JR
 
Hedge a little?

Speakers from an amp like a Fender have a pretty wonky frequency response to begin with so you're not really going to hear much of a difference even after 60 years. Heck you can have a few small tears in the cones and they still won't sound different.

Handwiring vs PCB doesn't matter at all. What does matter is implementation. If the manufacturer knows what they're doing, they can make a PCB version that will work exactly the same and be highly reliable. Unfortunately many manufacturers don't really take the time and care to implement things properly and the techniques are a little different because tube circuits with very high impedances and heaters and high voltages present different challenges. But I think I would trust Fender to do it correctly (although I wouldn't be shocked if they didn't).

The "amount of conductive material" should not matter at all. The old solid core cloth covered wire is thick enough that I don't think inductance would be in play (although current travels on the surface much more than in the core so not being stranded might impact inductance). But the inductance will be so small it will have no effect on anything at audio frequencies.

What could be a little different are transformers. When pushed transformers might sound a little different at LF. But again, that's all in the implementation.
Sure, I'm hedging a little, because I don't know, I was just putting some thoughts out there for discussion.

My main point was that "All parts used in nowadays circuits are objectively better." isn't really the case, for example the difference in reliability between a PCB and a hand wired amp. I've never been faced with a hand wired amp that is "beyond economical repair" whereas I have seen several much newer PCB amps that are.

I did say "Of course if there is enough conductive material, then there is enough and it shouldn't sound different" so thanks for reiterating that although abbey road d enfer and JohnRoberts have something to say about that which could explain some of the objectively obvious differences.

I suppose your conclusion "that's all in the implementation." is the answer we are looking for.
 
IMO vintage mojo is all about the talent that did great things at the right time, in the right place, with gear that had very recognisable character which emerged from the complex layers of subtle flaws, which ultimately is now familiar to us and distinct from other instrumentation.

For example. 80s and 90s Hip Hop fans will love the sound of an E-mu SP-1200. It has mojo because Marley Marl and Pete Rock had mojo. If not for that, then it might just be a terrible old POS.

Fender and Marshall amps have mojo because Hendrix had mojo.

I spoke to someone who had a ball for years downloading music in the early days of the web, and they thought the Real Audio digital compression codec had a cool sound to it.

Also, the more you cloud things up, the less detail you give to the senses, the less you dictate everything to the mind, and the more the imagination can kick in and fill in the gaps. If you've ever read fiction or taken acid then you might agree that the imagination can be more amazing that reality. I think this is the other part of why the inherent and recognizable distortions and noise in tape and vinyl make it so popular.

The only reasons I think there is seemingly a strong correlation between vintage gear and mojo, is that it had more character, and has had time to be soaked up and sink in, reflected on, missed, lost, become harder to find. Also as the years have gone by, designers and engineers have generally worked to remove the flaws, improve the specs, remove the noise and distortion, perfect the technology, and it's now so cheap, convenient, and available, that we don't get the time to really explore and enjoy the art, so the quality of everything is kind of been diluted in our minds.

Anyway, we're humans, and I think it's complex and subjective and largely in the mind.
 
After going through several years of evolution on the topic, my current thinking is that vintage appeal is down to two things:

1) The stuff that's real
2) The stuff that's not real (i.e. cognitive bias)

Sometimes old stuff is genuinely different. Metallurgy is one area in which things are often "not like they used to be" (transformer lamination material, plate and grid material inside of tubes, etc). Some of these differences are both objectively measurable and subjectively audible. Sometimes the new stuff measures better, sometimes the old stuff does. Sometimes the new stuff sounds better, sometimes the old stuff does.

If a modern high-end signal transformer has less leading phase shift in the bottom end than a vintage counterpart, you might hear that (and prefer it or not).

But also important: If something is really old and looks really cool with big meters and bakelite knobs, it might influence the way you hear it. And if my experience is any guide, the more you think you're immune to such bias the more likely it is that you're severely impacted!

Sometimes what people call "mojo" is really down to the way it feels to interact with a piece of history. If you were to remove the "experience" element and judge strictly by sound (i.e. a double-blind listening test), the preferences often (not always) become much less clear.
 
somethings you just can't quantify.
I had a company I worked with decades ago try and copy a transformer design in the hopes they could make a less expensive version of the name brand they were using. The idea was new part number, less costly, and some marketing spin and done. So after voicing my concerns, we had test samples made. When they arrived got to testing right away. After all the testing and measuring, the clones measured pretty well compared to originals while at the same time sounded something awful by themselves and sounded no where close to the originals.

Other times it can be something as simple as it looks the part so people and their brain say it is. For example, my current studio wants to make more modules for our desk, but they insist they get made like the originals with large ass wiring looms because that is what makes the difference.

Then other times, it's just belief. For example my buddy at an audiophile show once told the guy giving the demo that the cable lifters they used were the wrong ones for that type of demo music. He had them convinced they needed to use another kind. It was funny.

and sometimes it's in the details. Age can effect how things sound. Like an acoustic guitar that matures and sounds good when you get it and great after many years of being played.
 
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