lancaster amps

This page exists partially to extol the virtues of Lancaster audio equipment, but also to dispel the current myth of “if it is a tube circuit, it must be good.” Many elements must come together in order to make a great amplifier or a quality piece of studio equipment. This is not a knock on particular brands, but rather a general criticism of a majority of professional audio equipment. Lancaster Amplification combines high quality parts, a great circuit, and meticulous assembly to yield an heirloom quality piece of musical equipment that is both reliable and toneful.

The Point of Point to Point Wiring

What is the difference between a point to point and a circuit board piece of musical equipment?

Dave: The differences are tone and reliability. A point to point (ptp) piece of equipment, if constructed and designed well, will always sound better and be more reliable than a similar circuit board product. The PC board uses small traces, some no bigger than the hair on your head to make its connection. The tubes are starved for current. In certain parts of the circuit, the tubes can't get enough energy and this yields a brittle sound. Also, PTP products can always be serviced. With circuit board, all of the parts have a footprint, so when parts are discontinued, your beloved piece of equipment can no longer be repaired. It's planned obsolescence. Burnt PC board: Boo! Point to point: Yay!

Point to point techniques help eliminate oscillation problems without tone-suppressing circuitry by being able to provide space between sensitive components without adding parts. PC board products need oscillation suppression to keep from causing large amounts of damage to the amp and also RF suppression to keep from picking up radio signals. These additions to the circuit are absolute tone killers. With PTP, you can also use bigger, better parts.

How does this theory translate to the real world?

Dave: Let's compare what would happen if a point to point guitar amplifier or compressor falls down a set of stairs. A pot or two might break, a couple tubes might break, but all in all, it's an easy fix. There'd even be an excellent chance that it would work just fine.

Let's have a circuit board amplifier or compressor take that same ride down the stairs.The best case is that a few parts break loose off of the board. The worst case scenario is the board itself cracking and severing the tiny, unrepairable traces. This scenario doesn't even consider the presence of surface mount components, which are highly sensitive and are only serviced in a handful of repair facilities around the world. These surface mount components can be found in found in 70% of modern solid state audio equipment.

The Importance of High Quality Parts

Some people have argued that parts don't make a difference in tone, suggesting that better capacitors and resistors did not provide a better picture on a television so why would it make a difference in audio. What would you say to them?

Dave: I'm an empirical guy, so I decided to build the same exact amplifier circuit with high quality parts and another with parts found in mass-produced amplifiers (Marshall, Vox, Fender, Crate, etc.). The difference was astounding. The cheaper parts amp was overly bright and the overall tone was harsh and abrupt as the notes did not want to sustain. Keep in mind that this amplifier was the identical circuit assembled in an identical manner. Let's look at some of the parts that make the difference.

The output transformer is the most important in the amp. It is literally responsible for 30% of the tone. A quality output transformer has paper interleavings, which allow for it to breathe and cool. A better transformer self cools and has a wider bandwidth for a more natural and organic tone due to the wire's closeness to the iron core of the transformer. They're also literally 99% more reliable.

Clean, reliable power is essential to a great tone. This is accomplished in various manners. First, every Lancaster Amplifier over 15 watts has a filter choke. The choke is the turbo charger and gives the tone of the amp has more energy. Secondly, a rectifier tube, as opposed to a silicon diode, allows for a more detailed midrange and is very forgiving pc board is for computerswhen the amplifier starts to distort as opposed to having a harsh edge to it. Third, a quality power transformer has 30% more headroom in its rating than the circuit will ever use so the amp never overdraws the power supply.

High quality potentiometers are selected for both tone and reliability. Pots are inevitably limited in their life, and as the carbon wears, the pot becomes noisy, and eventually intermittent. Wiring PTP, any size or shape can be replaced. A PC board amp has every manufacturer using a different pot with a different footprint. Higher quality pots also last substantially longer.

I use different pots for different applications as they have different positive attributes. With a guitar amplifier, carbon film pots create a certain pleasing distortion not present with conductive plastic parts. In applications where distortion is not desirable such as bass amplification or microphone pre-amplifiers, conductive plastic pots are used in order to lower distortion and function in a more neutral manner.

Capacitors are the most critical parts for tone next to the output transformer. The coupling caps are the most important caps for tone. The better the cap, the more current can flow through it and the faster the capacitor can respond to the circuit. This in turn increases dynamic range, gives more slam, depth of tone, and greater articulation. Each Lancaster Amplifier has three types of capacitors to maximize the tone of the amplifier. Quality filter caps are also important as, aside from having greater longevity, they reduce noise in the circuit as they have less internal leakage.

Resistors are also important to the tone puzzle. Military-grade metal film resistors in the signal path have a very sweet presentation with absolutely minimal noise. Quality carbon composition resistors are found in the high voltage sections of the amplifiers to aid in driving the capacitors with maximum current drive to ensure properly supplied power. The cathode resistor in the output circuit is a military-grade wire-wound resistor providing 10 times the headroom that is required for reliable operation. These resistors combine for a greater resolution of tone and reliability.

The Other Pieces to the Tube Tone Puzzle

Does soldering technique really matter?

Dave: Yes, again, it is for both tone and reliability. An experienced tech hand-solders the part and works the solder into the pores of the metal making a nice dome of solder. Wave soldering (as found in mass-produced amplifiers and studio components) splashes the boards and in the hope that the solder sticks. This leads to a very high reliability problem. It also impacts the tone of the amp as it does not provide as thorough of a connection between parts. This leads to issues with noise as well.

How important is a good circuit?

Dave: As important as quality parts. The circuits of the past were great starting points, but to not improve upon them seems like a shame. Over time these vintage circuits have been blindly copied part for part without considering that they did have problems and could be improved. As a tech, an engineer, and a musician, I have scrutinized these circuits and taken the best and combined and modified them into something truly unique.

What do you think about PC board audio equipment?

Dave: Here, let me show you...

Dave Lancaster  smashy smashy

Extra! Extra! Tube kills PC board.
Dave Lancaster of Lancaster Amplification roughs up a PC board amp