300guitars: Hi there John. Can you tell us how you got started with your Sozo line of capacitors?

John Gaynor: Sure! To give you a little background, I have been playing guitar steadily since around 1975, I was a music major in college and then perused further education and turned out to be a full time engineer as my vocation. I think the whole Idea for SoZo started in the early 80’s when I started buying vintage gear. The reason I started is because I liked the clear sweet highs and the openness that only the point to point wired amps had. It wasn’t like nowadays as I’m sure you remember; there were relatively no boutique amps at that time, only mass production type amps (you young guys don’t know how good you have it!) I remember so many times when I went to check out an amplifier that was for sale, I saw so many hacked point to point amps that I had to pass on. We didn’t have eBay either, finding a part for an amp was hard! You had to buy what ever parts the local electronics supply had, if they even had the correct value in stock, much less the same type of part. With the inception of the internet I had the idea to develop and offer replacement parts for vintage tube amps. The one I started with was the most famous mustard cap.

300guitars: What exactly is a capacitor?

John Gaynor: A capacitor is two conductors separated by an electric insulator called the dielectric. An electric charge is deposited on one of the conductors inducing an equal charge of the opposite polarity on the other conductor; as a result an electric field exists between the conductor surfaces. The capacitor in a tube amplifier is used to pass the audio signal and decouple the high and low voltage points the amplifier circuit.

300guitars: How do capacitors affect the overall tone and response of an amplifier?

John Gaynor: Capacitors are a compact effective way to pass the audio signal (AC) to the next part of the circuit and block DC voltage. A capacitor has characteristics due to the different materials, shape, design, and so on. These characteristics sum when passing signal through multiple capacitors. This summing of resonance so to speak will affect the way the amp reacts and focuses…

DCP_1369300guitars: What are your Sozo capacitors based on?

John Gaynor: My original need for restoration was for the yellow mustard colored caps that were in the old Vox, Hiwatt, Marshall, (and many other guitar amps), so I started there. I now also have custom filter capacitors for Marshalls and Fender style caps.

300guitars: What are some of the special features of your Sozo line of capacitors?

John Gaynor: I am working on several types of capacitors currently but my original capacitors are based on the same material used in the Phillips caps in the 60’s. They are based on a polyester (Mylar) and aluminum foil. Most capacitors today are a metallized polyester. They vacuum impregnate the Mylar with an aluminum spray. They do not have the same AC pulse response as the true film and foil caps and you can plainly hear it.

300guitars: What is the difference between the Sozo Mustard Standard and the Sozo Mustard Vintage series?

John Gaynor: The Standard are a USA machine made true film and foil capacitor created with the same specs as the original Mustards. The Vintage capacitors are completely built by hand to get the correct lead attachment physics, temperatures, etc..

300guitars: Is it true that capacitors in general need a certain amount of time to break in?

John Gaynor: All electronic components change characteristics over time. The parts in your signal path like the resistors, capacitors and transformers have a very noticeable change. I like about 20+ hours on an amp. I notice a big difference in the musicality after about that time.

300guitars: What happens when they break in?

John Gaynor: They get much more open, musical, and relaxed.

300guitars: How long will a Sozo capacitor last? What is the life expectancy before replacement?

John Gaynor: A long time! I would like explain how good the new filter caps are here. A typical modern electrolytic capacitor is rated for 2000 hours; the SoZo Royal67 can operate for 10 years straight… 87,650 hours…!!! The film caps should last forever.

300guitars: What are your plans for the future of Sozo Amplification?

John Gaynor: I would like to develop some transformers, speakers, and amps one day. I am looking for the right partner and opportunity to do the R&D to make a truly superior product.

300guitars: Thank you very much John for talking caps with us. Your products are excellent and make all my personal amps sound fantastic!

John Gaynor: Thank You!

Click here to visit SoZo Amplification for more details and ordering.

300Guitars Shop

My shop is located at 1 Executive Dr Unit L Toms River, NJ 08755 Please feel free to email me if you have any questions or are in need of some tech work.
  • Monday: 10am - 5pm
  • Tuesday: 10am - 5pm
  • Wednesday: Closed
  • Thursday: 10am - 5pm
  • Friday: 10am - 5pm
  • Saturday 10am - 2pm. (I am in every other Saturday).
I am also an Eminence, Mercury Magnetics, Mojo Musical Supply dealer. I do all the tech work myself so you deal directly with me. I am a one man shop and my hours can vary so please contact me to confirm that I will be open. Email me: billy@300guitars.com Call or text me: 848-218-0362 Shipping Info for all repair work: Please ship all repairs to: 1 Executive Dr Unit L Toms River, NJ 08755
I am currently offering all phases of guitar work which includes:
  • Set-ups
  • Fret dressing
  • Re-fretting
  • New hand cut custom bone nuts & saddles
  • Electronics work
And amplifier work which includes:
  • Basic maintenance
  • Bias adjustment
  • Repairs and restorations
  • Modifications
  • And more....
Testimonials:
David Nicholas - The 20watt amp is sounding fantastic! Delivered the goods at the gig and I'm finding cool tones all over the place with it. Love the cab w Emenince Tonkerlites too- perfect for my sounds! Makes the 12 string sound like a grand piano!
Peter Lacis - I had an audition for something recently that was all about Led Zeppelin I -- my custom Pennalizer BLEW THE MINDS of the guys I was playing with. They couldn't believe the sounds coming out of that amp. That album was never in my mind when I came up with the idea....so that's yet another testament to the amazing work that you do.
Scott Goldberg - I am very satisfied with the set-up, and the fast turn around.  With the "lower" action it feels easier to play.  I will definitely spread the word.