The NiWatt
Not Your Grandfather’s 300B
The NiWatts continue to amaze people with their ability to drive difficult loads. Check this blog post to read about their encounter with a pair of Von Schweikerts. a 300B amplifier should not be able to drive such an inefficient speaker ... and yet the NiWatts do.
If you love the tonal beauty of the 300B tube, but long for more dynamic authority and rhythmic speed, the NiWatt is your amplifier.
If you are trapped between the delicacy and beauty of a 45 or a 300B, and the sense of unrestrained power of a 20 watt 845, the NiWatt is your amplifier.
Your grandfather’s 300B was about tonal beauty. The NiWatt pays respect to this aesthetic while building on it.
Old Meets New
To accomplish this, the NiWatt combines a classic circuit, fastidious attention to layout, and an extreme approach to power supply design. The power supply design was heavily influenced by Lynn Olson and his legendary Karna amplifiers.
Shown at the here is a pre-production prototype. Final construction will be metal as shown in the concept drawing, above.
NiWatt Amplifier: "B" Prototype
Grace and Power
Consider the ballerina – an artist/athlete who is a perfect expression of finesse and power – a dancer with precise footwork who is always in time and in perfect balance. A dancer who can bring you to tears.
This is the aesthetic of the NiWatt.
The NiWatt’s calling card is tonal beauty without compromise.
The NiWatt breathes life into your music.
Technical Overview
The Power Supply
The key distinguishing feature of the NiWatts are its four independent power supplies (and transformers). This was inspired by living with Lynn Olson’s personal Karna amplifiers for three months while Lynn was relocating to Colorado.
A pair of power transformers (B+ and filament supply) are dedicated to the 300B output tube. A second pair of power transformers (B+ and filament supply) are dedicated to the input and driver tubes.
Separating the output tube’s power supply insulates the input and driver tubes from the harsh demands placed on the output tube. This contributes to the perception of a dramatic increase in power, because the driver tube is never under stress.
It is for this reason that we encourage you to compare the NiWatt with both push-pull 300B amplifiers as well as “transmitting tube” amplifiers like those based on the 845 tube (20 watts). We think you’ll be surprised at how authoritative the NiWatt sounds in comparison.
Damper diodes (tubes) are specified in place of conventional rectifiers. Their high current capability conveys rhythmic speed and their reduced switching noise contributes to delicacy and nuance. Refer to the tube section for more details.
Principle #1: when you listen to music through your hi-fi, you are listening “through” your amplifier’s power supply.
Principle #2: with directly heated triodes (because of their low distortion), you are actually hearing your driver tube. This is the key reason for the four independent power transformers discussed above.
Construction
Mirror imaged pairs.
We go to this extra expense in support of implementing the shortest signal path from input jack to speaker terminal.
There's a total 5″ of signal wire in the positive side of the signal circuit – total!
This circuit is so revealing that auditioning various samples of a 3″ length of wire was clearly audible.
Copper Ground Plane and "Roadie-Proof" Construction
Prototype Chassis & Copper Ground Plane
No expense was spared here. This copper ground plane, along with the extremely short signal path is a key contributor to the NiWatt’s remarkably low noise floor and speed.
Hybrid, point to point wiring / turret board construction
Ease of maintenance, and immunity to shock. This is the same construction method used in guitar amplifiers which are almost impervious to abuse from “roadies”.
Parts matter
Every part must justify its place in the NiWatt – from the 3″ length of wire referenced above, to the smallest resistor, and as noted above, the NiWatt is extremely responsive to parts changes.
The most expensive part was not necessarily the best suited to the task. For example, our NOS supply of Black Gate power supply capacitors did not fare as well as power supply capacitors which could easily have been overlooked if one specified parts based on price or reputation.
Of course, there are places in the circuit demanding of premium parts. The copper ground plane is but one example of this.
It’s also no surprise that premium output transformers justify their place in the NiWatt. We are currently specifying output transformers from both with the demise of Magnequest we are specifying Hashimoto.
Circuit Topology
RC coupled
A classic circuit topology which has withstood the test of time.
Direct coupling has its advocates, but we’re not fans. The key reason is that we've found that the benefits conferred by independent power supplies produce far more gains than any theoretical losses from quality coupling capacitors.
Three stage design
Input, driver, and output stage.
We are firm believers in separate input and driver stages, because the input tube’s job (voltage gain) and driver tube’s job (current delivery) is very different.
Asking a single tube to perform both functions is like asking your BMW to haul a cord of firewood.
Phase inverting (3 gain stages)
An amplification (gain) stage (either a tube or a transistor) inverts phase, so an even number of stages is non-inverting and an odd number inverts phase. Simple, huh?
Ask your manufacturer, because you can’t just count tubes (and it’s really hard to count transistors). Some tubes have dual sections (which may or may not be used), and other tubes may not perform amplification functions (i.e. cathode follower).
Tube Compliment
Rectification - 4 damper diodes (6AU4)
Traditional rectifiers (5AR4, 5U4G, etc.) are dual diodes (two diodes inside one tube). Damper diodes have a single diode, so replacing a 5AR4 requires two damper diodes.
One diode pair provides high voltage to the 300B & the second pair supplies the input and driver section.
Signal tubes
- 1 6SN7 (input tube)
- 1 6V6 in triode mode (driver tube)
- 1 300B (output tube)
The musical benefit of damper diodes
Most individuals are unfamiliar with damper diodes. They have much lower switching noise. This translates into a less “hashy” sound than even the best new old stock rectifiers.
They also have much higher current capabilities than normal rectifiers. All things being equal, damper diodes follow musical transitions with more finesse and speed.
Damper diodes in plentiful supply in new old stock, and as an added bonus, they are priced lower than what you’d pay for current production 5AR4’s from Sovtek, JJ etc.
How does it get better than that?
Pricing
Introductory pricing: $17,995
Please refer to our COVID statement for current updates on travel and customer interaction.
Yes, COVID has delayed the official NiWatt launch, but we’ll build you a pair at this introductory price.
Price includes:
A $500 travel rebate:
If you visit Galibier to audition and purchase a NiWatt within one year of your visit. Visit Colorful Colorado on our dime!
Free Power and Speaker Cables:
NiWatts are delivered with two Wind River Power Cables and a single-wire set of our Wind River Speaker Cables.
If you have already purchased any Wind River Galibier cables in the past, we’ll credit you for the price you paid for any three cables. Credit is for the price paid, less tax and shipping.
We strongly recommend the Wind River cables however, if you are considering plugging in the Headwaters line, however.
Cable notes:
These cables are not “throw-ins”. They were instrumental in the prototyping and development of the NiWatts. We needed better tools, so we had to design them.
