Soldano Custom Amplification was born in 1986 from Michael Soldano’s personal desire for a better guitar amplifier. He had tried many of the amps on the market at that time and felt there was something lacking in their sound and performance. This set him out on a quest for the knowledge needed to build a high gain circuit that would not turn to mush in the bottom end when pushed hard and would retain clarity and string to string definition even in the highest gain settings. With his newfound know-how he started to work on his own amplifier. At every stage in the development of this amp, Mike would take it to guitarists who's playing and ears he respected in order to get their opinions about the amp's sound and overall musical quality. Finally, he had the amplifier that he was dreaming about for all of those years: the SLO 100.

For Soldano, building amplifiers isn't only about a pursuit of tone. It is also a desire to build an amp that is bullet proof right out of the box. Michael's intention was to get these amps into the hands of the best guitar players in the world, and he knew that they would expect their gear to work flawlessly night after night.

Here at Soldano, we are still dedicated to building the highest quality amplifiers possible. From our Atomic 16 and Astroverb to the legendary SLO100, each amplifier is built completely by hand in our Seattle, WA facility. In fact, a single technician builds each amplifier from start to finish. We feel that by not using a production line approach we can keep our quality control where we want it: second to none.

 

Mike Soldano describes the finer points of Soldano Amplifiers:

Chassis
All of our chassis are made out of heavy-duty 16 gauge cold rolled steel. They're all powder-coated, so they don't rust, and it makes them look attractive. All of our amplifiers, except for the Astroverb/Atomic series, have corners that are fully heliarc welded, which gives our chassis a clean, finished look.

Transformers
The transformers we use are very high quality. The 100w Super Lead Overdrive (SLO-100) uses premium, audiophile-grade transformers made by DeYoung Manufacturing. These exceptionally well designed and built units make the SLO a much higher fidelity amplifier than most other amps on the market. The SLO transformers are warmer, smoother, and more dynamic sounding. I believe that these transformers can't be beat.

In all of our other amplifiers, we use extremely high-quality industry standard transformers, designed and built by Mercury Magnetics.

Hardware
All of our transformers are mounted with very substantial screws with self-locking nuts on them. Why? I've repaired so many amps in that past that have had the transformers hanging on by one screw, because over time, all of the nuts had vibrated loose. It's a pretty common problem: anything that's audio vibrates, and vibrations can cause the fasteners to back off. We use nylon-insert locking nuts and high-grade fasteners on all of our transformer mountings to eliminate this problem.

Our circuit boards are mounted in the same fashion. We use machine screws with captive lock washers, so that nothing will shake loose.

The threaded standoffs that the mount the circuit boards inside our amps are made of aluminum. We do not use any nylon or plastic standoffs, because I don't feel that screws can't be tightened enough to rigidly keep everything in place when using these. Another problem with nylon is that it will hold the threads fine when the screws are first tightened, but if the amp needs to be serviced and the screws are taken in and out more than a couple of times, the threads become worn. If service needs to be done to our amplifiers, we know that screws can be taken in and out of the aluminum standoffs without worrying about the threads stripping out. They cost a few pennies more, but they're well worth the expense.

Tube sockets
In our SLO amp, all the tube sockets are chassis mounted. Why? Because that's the way I did it when I first started building them. I believe that it's sort of what defines a top-end, well-crafted amp. It's not necessarily any better than a PC mount, it's just different. All of our other amps have PC mounted preamp tube sockets, and we're now experimenting with PC mounted sockets for the power tubes as well. We finally found a high-end quality socket worthy of doing it. In the future, we will probably move more towards PC board power sections, because I feel we can offer more value by cutting our labor costs. We will continue to offer the power section on a separate board because approximately 90% of all catastrophic tube amp failures (mainly arced-out sockets) occur in the power section. If such a problem occurs, it can easily be serviced by just replacing the small power board.

Circuit Boards
All of our circuit boards are designed with extremely wide traces and very thick (2 ounce) copper. We are currently using double sided boards in all of our new designs. The SLO is the only amp we still build with single-sided traces -- and that's just because I didn't want to change how the SLO is designed and built, and I originally designed it with a single sided board. The way it's laid out and assembled, it works perfectly well.

The double-sided circuit board allows us to fit more electronics into the design with less external wiring. By doing that, I believe we're able to offer higher value in our products. At Soldano, we don't compromise our parts quality to get the price lower. We try to do what we can to reduce our labor costs, and one way to cut labor costs is to design more of the amplifier into the PC board.

Point to Point vs Circuit Boards
At this point, since I'm sure you've read a lot of crap dissin' PC board design, I would like to present an excerpt from a technical article I wrote:

In the early days before circuit boards were designed, technicians relied on various "anchor points" to connect wires together. Primitive layouts consisted of terminal strips screwed to the chassis or even pieces of cardboard fitted with brass eyelets. Components and wiring were then soldered, point to point , to these terminals or eyelets to create the circuit. As time went on, clever technicians figured they could etch the wiring patterns into copper foil laminated to a strong and rigid phenolic board. The components could then be soldered directly to these copper "traces". This was the beginnings of modern printed circuit (PC) boards. In today's boards, epoxy reinforced glass fiber replaces phenolic and more than one layer of copper is now possible. When using PC boards, precise parts placement and consistent wiring is guaranteed.

I feel that point-to-point wiring is still very useful when designing an amplifier prototype or building a custom one-of-a-kind amp. It's quicker, easier, and cheaper to do than a one-off printed circuit board, and it's generally easier to make circuit modifications when using this method. Well done point to point wiring is also very nice to look at - if you've ever seen the inside an early Hiwatt, you'll know what I mean.

In my opinion, however, it is far more cost effective and less labor intensive to use PC technology in a production environment. To you the consumer, this means a better amp for less money. I believe that an amp built with well designed circuit boards is easier to work with, is far more consistent and reliable, and more rugged mechanically than a point to point wired amp. Another advantage is that, since the circuitry is clearly mapped out on the board, PC boards are also quicker and easier to service.

In closing this discussion, one should bear in mind that there is absolutely no sonic difference between point to point and printed circuit board wiring. Detractors of PC boards have argued that they are less reliable do to cracked solder joints or failure prone do to burned traces - neither of these complaints are even an issue with a properly designed board.

Potentiometers
The SLO uses hermetically sealed, military spec pots made by Claristat and/or Alan Bradley. These are by far the most expensive audio potentiometer you can buy. Since the SLO is designed to be the Ferrari of all amplifiers, we use these pots. The pot is made from stainless steel, and has a fully sealed brass shaft. Additionally, it has an epoxy seal that glues the cap to the body, so they can literally be immersed under water and still work. Due to the high cost of these pots, we can't use them in our more "user-friendly priced" amps. In all of these other amplifiers we use very high-quality semi-closed pots from CTS.

All of our potentiometers use standard, full-size quarter inch solid aluminum or brass shafts with full-size 3/8 inch brass bushings. We don't use anything with plastic shafts or bushings, because if the amp gets banged around in the tour van or something mashes into it, these parts can snap right off. This won't happen when using metal shafts.

Components
The components we on the PC boards themselves are the finest we can buy. All of our resistors are metal film. I don't believe in carbon comp resistors, even though there's a lot of "voodoo" or "hocus pocus" around the vintage circles saying that they're different or better. The hiss (noise) factor is so much higher with carbon comp resistors than with metal film. This is unacceptable, especially in high-gain amps. Metal film resistors are quieter and more precise.

All of our resistor values carry a 1% tolerance whereas the standard carbon comp resistors carry a tolerance anywhere from 5-10%. This is one of the reasons our amps sound consistent. Studio engineers have made comments such as, "We had an SLO in here last year, and someone just brought one in the other day and it sounded exactly the same." Our amps should sound the same, due to the fact that we use very close tolerance components. If you start using parts that have as much as a 10% tolerance drift, you can have two of the "same" amps that sound completely different. For example, the amp design may have a requirement for a 100k resistor, yet due to tolerance drift, the actual resistor in one amp is only 90k. A second amp might have a resistor in the same spot that's actually 110k. Now you have a span of a 20k difference in resistance in just one resistor. If you take 100 components like that and start scattering them around an amp, you're going to get amplifiers that sound completely different from one another. Carbon comp resistors, which already start out with a loose tolerance, can change with age. Metal film resistors stay very consistent.

Filter capacitors
We use much more than adequate filter capacitors in all of our amps, giving them more headroom and faster dynamic response than other amplifiers. In this area, the old adage "If a little is enough, more is better" definitely applies.

I build everything with a very large safety tolerance as well. If a part is rated at 400 maximum operating voltage, I will run it at 300, because I don't want to put something right at the edge of tolerance where it will risk failure. I try not to go overboard with this, however. If something is supposed to be operating at 300 volts, I'm not going waste resources using a 600-volt part.

For service reasons, I try to use all standard components that are readily available. If a person has an amp blow up in the middle of nowhere, we want to use parts that, in a pinch, can be replaced with something right off the shelf of your average TV repair shop.

I don't believe that there's any reason to build voodoo and mystery into an amplifier that's supposed to be used as a tool, because it's going to be frustrating down the road for the end-user. Sure, maybe it would make us richer because we could sell exclusive parts for our amplifiers, but it pays no service to the customer whatsoever - and we care more about our customers than our pocketbooks.

Wire
Wherever possible, we use silver plated copper stranded teflon insulated wire. Why? Because it just simply is the best, there's nothing better. It has great conductivity, it doesn't corrode, and it solders nicely. This translates to better quality control so we have more reliable and consistent solder joints with excellent integrity. If someone wants to change something in the in the future, it's a lot easier to unsolder a piece of teflon insulated wire because you don't have to worry about melting the insulation with a soldering iron.

Knobs
We choose knobs mainly for aesthetics. Once I decide on the design of the knob, I pick the best mechanical knob I can find for that look. As a result, we have the phenolic knobs we're using for the Decatones, which are better than a basic plastic knob, and they look great. The SLO uses a knob that contains a brass "collet" to lock onto the shaft and it's one of the finest knobs money can buy.

Pointer knobs are very functional and very practical, making them easy to see from a distance. We incorporate pointers on many of our designs, and will continue to do so because we like them.

Perforated Metal Grilles
The initial reason I used these on the front and back of my amp heads was for aesthetics. I thought the interesting part of the amp was the tubes and the transformers. I was in love with the way tubes looked when they glowed, so my initial reasoning for using see-through grilles was to see the glowing power tubes. The original Philips 6L6's we used glowed a cool purple. The secondary effect of these grilles is the excellent cooling that occurs through natural convection, so our tubes run much cooler than other amplifiers. Our underchassis components and our tubes last longer because they aren't on the verge of melting. This is a perfect example of a very nice marriage of form and function.

Cabinets
The cabinets we use are very robust, and are made out of 3/4 inch marine plywood, and are covered with a durable vinyl of which we offer a wide variety of custom colors. We use Sessions corners, with stainless steel screws that don't rust. Nickel-plated screws have the tendency to rust when nicked with a screwdriver. Additionally, we use heavy duty Ernie Ball handles.

In Closing
I try to design amplifiers that are timeless. The SLO was originally designed in 1985, and I think that amp looks as good today as it did when it was born. When I design an amplifier, I try to design everything with simplicity in mind, using clean and classic styling and layouts that aren't crowded or confusing. I try to stay away from trends and fads, so that 40 years from now my products will look and sound just as contemporary as they do now.