Power Amps Vs Integrated Amps
I’m a big fan of integrated amplifiers as a product category. They offer good value as you get a preamp and power amp in one box. Sometimes you get built in phono and a DAC as well. If all of these components are dealt with diligently and the real estate is ample, you get a cost effective product. I like ‘em. Buttt…
There’s no substitute for a fanny kicking, full on Tyrannosaurus power amp DONE RIGHT. Getting massive power vs respectable power (in an integrated) will make quality speakers (like Brystons) achieve heights they otherwise couldn’t scale.
The catch is, to get power amps built well enough to eclipse the performance of good integrateds is usually very expensive.
There’s no question Bryston power amps will make your speakers perform much better than an integrated. It takes a few bucks.
3B Cubed $6000 (200×2)
4B Cubed $7500 (300×2)
However… what if you could get performance COMPETITIVE with Bryston at only 40% of Bryston’s price point? What if such amps were made in Canada with a 5 year warranty vs made in China with a two year warranty? What if this Canadian amp was built like like a tank? What if it had great headroom instead of smashing full on to a brick wall at rated power?
What if it was made… by Bryston?
Would you be interested? I hope so.
Bryston/Axiom Merger
Bryston created a speaker line in 2011. Bryston hired Axiom, a friendly Canadian company down the road a piece to build Bryston speakers to its specs. The project turned out to be a tape measure home run and the companies soon merged. The resulting entity is simply called BRYSTON.
The upper crust speakers and electronics are labeled Bryston. They push the state of the art in terms of component quality, muscle, resolution and have a 20 year warranty.
Bryston has retained the name Axiom for its more price sensitive speakers and electronics. Axiom is also made in Canada and offers a generous 5 year warranty. That’s right, Axiom isn’t made in China, but its gear is priced similarly to the big names that are.
Axiom’s new power amp is now here. For similar money to what’s coming out of Asia, you can get Canadian built power and quality with a solid five year warranty. This isn’t a generic amp. It is built to a higher standard and delivers a myriad of benefits compared to what’s coming from the other side of the planet.
Axiom Power Amp
Bryston and Axiom engineering teams have shared brain power. The new line of Axiom ADA1000 amp is now shipping and offers superior performance to the highly advertised names we all know.
Axiom uses significantly bigger power supplies than the imports. Axiom employs large toroidal transformers. LINEAR power supplies AND much larger banks of filter capacitance. The benefit of this muscle is that Axiom has superior headroom, dynamics and bass response compared to its similarly priced competition. Because the power supplies are linear and gutsy, Axiom can drive low impedances much better than the big advertisers. Take a look at the filter capacitance and weight of the various Axiom amps compared to the Chinese.
If you have a modestly powered integrated amp today, you should consider adding the Axiom power amp to MUSCLE UP and bring a new level of acceleration and excitement to your speakers.
You can run pre out from your integrated into the Axiom amp- and achieve the verve of a sports car instead of a modest sedan. The better your speakers are, the bigger the improvement you’ll get by adding the Axiom amp.
If you have ANY surround receiver now, you should consider adding an Axiom amp to improve your propulsion. There’s a dirty secret to the power ratings of surround receivers. They all fib in their specs. They pull trickery by claiming power with one channel driven at a time at 1k, at 1% THD. If they were honest, they’d claim power while running ALL channels, 20-20k- at .05% THD. Surround receivers run SMPS supplies and don’t approach their advertised power. Further, and even worse, they have no headroom for musical demands.
Running a surround receiver is like running multiple showers at the same time in your house. The water pressure goes to nil. A surround receiver claiming 100×7 actually performs like a stereo integrated amp running at a third of that- if you’re lucky, with no headroom to boot. Think of driving a car and you need to stomp on the accelerator to pass- and there’s virtually no jump or response. When the music demands peaks, surround receivers are wimps.
Using an Axiom ADA1000 is like running a fire hose compared to a garden hose. Let’s give your speakers the drive and control of Axiom. Or Bryston!
Amplifier Topology
Axiom’s “magic” in amps is to run Class D with some innovative twists that deliver oceans of headroom. To achieve this level of performance, Bryston builds its Axiom line of amps with a secret sauce topology, which vastly outperforms your average bear.
If you’ve had a prejudice against Class D, it’s time to rethink that. I’ll spell out why Ds aren’t the same, and why Axiom is much better than the other guys who use it.
Traditional class D amps use computer power modules to deliver power. Axiom does NOT use traditional D modules like B&O and Hypex. Axiom has created a technology where it runs MOSFET output transistors in a D mode, which takes advantage of high efficiency and eliminates the endemic distortion of mismatched transistors.
To be clear, there’s no other amp design out there quite like Axiom’s, much less, built in Canada with a 5 year warranty.
Toroidal Transformers
The amps start with very large TOROIDAL TRANSFORMERS. They are quiet and harness the magnetic field within the confines of the transformer to minimize RFI. The imports use more noisy EI core designs that spew RFI all over the PCB, which creates a more cloudy sound.
Linear Power Supplies
The power supplies are LINEAR, meaning, non switching. EVERYONE else and their brother run moderately priced amps (whether D or AB) with SWITCHING (SMPS) PSUs. This keeps the cost low and measures fairly well into a test resistor. But it doesn’t deliver the Herculean muscle and HEADROOM that Axiom amps have into real speakers when music demands power on peaks.
Massive Filter Capacitors
Axiom employs enormous capacitance in its Linear Power Supplies. When you check the fine print you’ll see the Asian imports provide tiny caps and claim it doesn’t matter. Of course- IT DOES! Axiom amp filter caps run 60,000uF, 108,000uF or 144,000uF, depending on the model. You’ll be lucky to get 10,000uF from the other guys. Axiom has custom caps that are 105 degC (most of the other guys are 20% less) rated and have high ripple current capability.
Other Build Factors
Most amps use dental floss sized wire from their PCBs to the binding posts on the rear panel. Axiom uses metal plates that are soldered at the board and to the posts. No flimsy wire in the road.
Axiom’s PCB is screwed down with 18 screws so there is no trampoline action in its behavior.
Speakers Aren’t Test Resistors
Amp manufacturers give you specs into a steady tone, 8 ohm test resistor. Let’s say we’re talking about an amp with a switching (SMPS) power supply. The amp may produce 300w into this resistor- but there’s no headroom.
Music isn’t a flat road. It has peaks and valleys. For highly demanding passages you want your amp to jump like Michael Jordan for short bursts as peaks demand. Here’s where Axiom excels.
Brand X amp that is 300w, with SMPS design, will be lucky to hit that 300w. It has nothing more for the peak demands. It’s toast at 300. Now 300w sounds like a lot, but not compared to Axiom’s power.
Axiom’s amps have enormous dynamic headroom of triple the RMS rating of the amp! For musical peaks of a split second here or there, Axiom can jump out of its shoes and scale heights the other guys CANNOT.
A 300×2 competitor with an SMPS supply will flat out quit at or below 300w. Axiom rallies to hit crescendos and peaks that leave the other guys sounding dull. Axiom’s ADA1000, for ex, is rated at 125×2. It peaks at 375×2. In the real world, ADA1000 is more powerful than the other company’s 300×2 amp with zero headroomU+0021
A Word About Class D Designs
Some audiophiles aren’t open to D designs. That’s a sad prejudice from 20 years ago. There are some distinct advantages to this technology. And Axiom takes D to a new world of performance. Here’s how Ds work.
A Class D design has four main building blocks:
1) A triangle or saw tooth wave generator to create the switching pulses- PWM.
2) A comparator that is responsible for modulating the switching wave form.
3) A gate drive circuit that turns the output devices on/off in time to the switching wave form.
4) An output stage consisting of power transistors or MOSFETs.
When you buy an amp with an off the shelf D module by Hypex, B&O or anyone else,
all aspects of these four stages are SET and the same as other amps using the same modules. All you have to do, to make it work, is throw a power supply in front of it.
Axiom doesn’t use off the shelf modules- not that they’re so horrible. But Axiom chooses to use its own CREATIONS to have full control of all stages of this design. Each can be optimized for its task as Axiom sees fit. Axiom bakes its own cake from scratch. It doesn’t buy a pre made cake and just spread icing on it.
The Axiom power supply in front of this Axiom module, if you will, is LINEAR with a huge transformer and massive filter capacitance as described above. Axiom’s design is based around its own module, which incorporates its own method of running the wave generator, modulator and gate drive. This Axiom module drives discrete, high current MOSFETs. Further, Axiom runs its own low voltage power supply, a feedback circuit and protection circuitry. To be clear, this is an Axiom built module with their own technology. Everyone else buys a module from a vendor and works with it- virtually a generic option.
Readers with a good memory might ask, isn’t there a concern about the MOSFET transistors being mismatched and creating distortion? There are no such worries with Axiom’s D design where the transistors aren’t run in a linear mode, they’re run in a switching mode to match the musical wave form. The sound stays smooth because there are no grainy artifacts from distorted or mismatched output transistor behavior.
The punch line to all this TLC is that Axiom is able to have a scalable Class D amplifier where all the core parts stay the same among the models, so the sonic signature is the same within its family of amps. Axiom builds the entire amplifier in house, including populating the circuit boards to have full control over every component that is used. If you buy an amp with a Hypex module, for ex, you get something more last fast food than fine dining.
Axiom ADA1000
ADA-1000 $1390 (125w/ch 8 ohms, 250 w/ch 4 ohms, RCA only)
(5.25h, 17.75w, 16.75d)
ADA-1000 has 60,000uF caps and weighs 44 lbs
Let’s compare ADA-1000 to a popular high powered amp from Crown, SLS2502. Crown is an example of mass produced D amp with SMPS power supply from China.
| Axiom | Crown |
| Made In Canada, 44 lbs | Made in China, 10.8 lbs |
| Rated power 125×2, peaks @4000w! | Rated power 440×2, peaks @440×2 |
| Toroidal Transformer | EI Style Transformer |
| Linear Power Supply | Switching Power Supply- SMPS |
| D design with discrete transistors | D design with IC chip drive |
| Filter Capacitance, 60,000uF | Filter Capacitance, 6,000uF |
| Filter Caps rated to 105 degC | Filter Caps only 85degC, shorter life |
| THD .05% | THD .5% (Ten times higher than Axiom) |
| Wide bandwidth | Limited bandwidth with brick wall above 20k |
| Passes signal purely | Resamples with built in A to D converter |
| Silent through spkrs when music paused | Hiss through spkrs when music paused |
| Substantial heat sinking, no fan | Very little heat sinking, uses noisy fan |
| Very low cross talk | High levels of cross talk |
| Impervious to AC noise | Susceptible to AC noise |
| Come with isolating feet | Doesn’t come with any feet or rubber pads |
| Sounds warm and open | Sounds DRY/glassy: must soften with preamp&cables |
| Clean PCB | Massive amounts of glue on caps and PCB Looks like bird poop, sloppy mass production |
| Capacious design to avoid noise | Parts literally touching, caps/transformer/drivers Results in RFI & noise |
