Coupling Cap Tone Comparison 

What I think this proves is in a healthy amp, ie no leaking coupling caps, any one will work admirably. In a guitar amp a 75 cent Mallory 150 works as well as as a $10 Jupiter.

" If it ain't broke, don't fix it", I wish I would listen to my own advice. I had a Strat sounding nice and springy and bold with a Lunear 250kk and a wima .01 and a Yellow Mallory .022uf ( my brain said" leave it alone") but after watching too many vids I got a audio taper and a silver paper in oil(Wires were v. Flimsy)and it sounded horrid. I tried various other caps but no joy. I realised it was the Potentiometer that seemed to thin the sound out. Found a Wima .047 and a CTS linear and almost as good as that 1st set-up. You have to bond with your instrument/amp and in my case I learned the hard way. Linear for tone, Audio for vol or whatever works for you.

Your right, every nut, bolt screw, cap, resistor, wire, valve, speaker and even the solder and pots make a difference. It has to be trial and error and if you are going to buy a new/used amp try to test it with your own Guitar or at-least as close as you csn get. Thanks.

Enjoyed this experiment. But I did notice the omission of ceramic disc caps. I don't use them for coupling caps. But I have heard some builders insist on them to achieve a more "vintage" tone. In a head-to-head comparison like this one, it would have been nice to have had them in there too. As you noted, there is more going on in the "organic" nature of tube amps. They can seem temperamental at times and not always give the same response. Part of that has to do with how interactive ALL the components are in the totality of the circuit. Changing one cap or resistor can sometimes make a huge difference in what we hear coming out of the speaker. But it's not really the change of that component that is making the difference. It is about how that changed component is now interacting with the other components that haven't been changed. Tube amps really are finicky, frustrating, fascinating and fun little beasts! Thanks for this video. 🙂

I just built a tweed 5F2A out of junk I had in the drawer. Old 1000v Sprague couplers from the 80's and a mixture of metal oxide, carbon film, and carbon comps from the last century. It sounds amazing. Every bit as good as my vintage amps with the "mojo". IMHO the single biggest differences perceptibly, are between things like using class two ceramics instead of films in the tone stack and the size of any cathode bypass capacitors. Those two things alone made more impact than coupling caps.. Nos 6V6GT's sounds better to my ears too (and can be had cheap). I like the Brimars!

9 and 3 were my faves.

I assume you checked the caps to find the outer foil lead and connected that to the lower impedance point in the circuit or ground when necessary?

Been there done that to my surprise i preferred the 716p it provided more clarity when amp is overdriven chords are a lot clearer and crisper not as woolly as others.

With a 20% tolerance value in capacitors, the values need to be measured to find two that are within 1% of each other to make the comparison accurate.

Any noticeable change with volume and gain either through goosing it up or a good boost/fuzz/overdrive? Definitely some differences.

I thought I heard a difference in #3 and #8. I think the difference is more or less apparent depending on where in the circuit you use them. I have done this sort of test in a blackface fender and a trainwreck type build, and in some positions there is a very tangible and noticeable difference. While measuring capacitance to ensure values are identical. The biggest difference will be changing between construction styles, so if you swap an old ceramic coupling cap for a poly film for eg you will notice a change in character right away.

the perfect, yet equally luxurious companion will be if you include the Mojo Dijon, Vishay 1813 and Panasonic ECQ-E tops in the video. You'd be practically analyzing the most debated ones!

Impossible with just 2 coupling caps to hear much difference. Perhaps a different feel for the player? Maybe in a Marshall or bassman circuit there would be audible difference. As you say.

Nice Video... Im building a Deluxe Reverb and im mixing Jupiter Yellow Vintage with blue sozos on the .047 coupling side manually because I didnt find .047 in yellow.. I could have used .05 but if quality control on these brands are true to tolerances I wanted to start out with correct values that show in schematic as I could get for baseline...

Every forum I go on says they sound different but every video I watch comparing them sounds the same, it's kinda like how bigfoot sightings went down when everyone got hd camera phones

Close your eyes and listen all the way through, then listen with your eyes watching the screen. That tells you what is really changing.

Out of the nine.... I got both oil caps correct, but just guessed at the others. My favorite was the Jupiter Yellow Mustard. Don't know why.

A clean tone or two would have helped greatly to differentiate. Thses all sound virtually the same except the 715s OJ and the Suntan's perhaps a bit less "organic." Why anyone would spend 5x or 6x times more for Mallory 150s is beyond me unless they like the way the more expensive caps look.

I also wonder if the caps were measured to make sure they were the same value. 10% of .022 is .0022, thats 2200 pico farads. 100 pico farads can easily make a difference is tone. If 1 cap is 10 over and another 10 under thats 20%!!! Many of the 10% caps I measure are as much as 15% off. Even many of the 5% micas I measure don't meet the spec.

There are subtle differences, I don´t care much for the Mallory´s. Another thing is parallel caps on guitar tone controls, they just bypass the treble and make no difference at all to me.

When they're so bad you can hear it on a cell phone 😂 couple of those were horrible.

Do a full Bode plot of the circuit with every capacitor after measuring the exact value of all of them. If the values are identical, the Bode plots, and thus the frequency response, will be identical. Caps are caps, they sound the same if the value is the same. Test equipment that is far more discriminating than your ears just confirms this.

The one thing none of these listening tests seem to take into account is placebo effect or expectation bias and that our auditory memory is only about a second or two. Even in a test like this where u have one after another by the time you get to #3 your brain has lost the tone of #1. If you have to go back and forth listening then anything you hear is going to be placebo, unless of course it's a huge difference where there's no question. Like when comparing different values of components. Main thing with caps is just get good quality that will be in tolerance and last. When I first saw bumblebee reissues for a hundred bucks or so a pair I almost LMAO. If you wanna spend that for a vintage correct look OK but they sound no different from a good regular cap. And you have to measure the caps to ensure they are exactly the same value, just 10% difference can affect tone.

I'd rather replace my old strings.

They all sound the same

IC caps are the worst. Especially their lytic caps. They leak and fail prematurely all the time.

Bullocks you erars can't tell the difference 😂

Sounded the same, as should be expected. If you understand how nothing actually passes thru a cap you'll get it. they charge and dis-charge. There is no connection between the leads so no current ever flows "thru" them. Guitarists need to learn about placebo, audiophiles have but still totally deny it. Our ears are really the worst for a true representation.

There was no way I could tell. Distorted electric guitars make me cringe. Some scintillating cymbals, or crisp acoustic guitar would have been better. Or a natural, unprocessed human voice...

Coupling cap sound with various capacitance values would be the right way. Where was the coupling capacitor placed in the circuit? There are too many coupling capacitors in a circuit. What you have done has no meaning. I would consider this whole video as a junk made by a non technical person. Regards..