Something special this way comes! Allnic has discontinued the A-2000 25th Anniversary, KT150 stereo power amplifier, and in mid-February, we will have available fifteen (15 only) “hot-rodded” A-2000 25th Anniversary amps - at a truly exceptional price - $5900. The A-2000 25th Anniversary is a 100 watt/channel powerhouse and paragon of clarity and finesse. With the modifications it sounds even better, and for the price, we think nothing will be able to touch it. It’s a great way to end the A-2000 25th Anniversary’s production run, and a great opportunity, limited by number of course, for anyone wanting a brand new Allnic power amp, one that can drive virtually any speaker, “for a song”, so to speak.

 

This small miracle came about because David Beetles, Allnic’s North American distributor, negotiated a special deal with KS Park to purchase the remaining fifteen A-2000 chassis and have them modified to elevate performance. The enhancement consists of a refinement of the circuit, including the use of a pure triode, rather than a pentode wired in triode, for the four second-stage drivers. The replacement triode, the 6S4, used in the M-2500 monoblocks, brings more SET refinement to the power and clarity of the amp’s push-pull design – and it’s more commonly available, too.

 

This is a limited, one-time, and as I said truly exceptional opportunity. If you’re interested, give me a call, text, or email. If you’re in Canada, contact David Beetles (west) or Don Corby (east). There might be a line up for this one!

Allnic Monoblock Amplifiers - What does the "A" vs. "M" signify?

 

In May 2020, Anthony Kershaw of Audiophilia posted a review of the Allnic M-2500. Thoroughly impressed by its remarkable ability to combine power with single-ended triode (SET)-like purity and transparency, he gave it an Audiophilia Star Component award. A little less than a year later, we see the newly released A-2500 monoblock amplifiers. What do the “A” vs. “M” designations signify?  First, let’s look at the “2500”, which refers to the chassis design only. Allnic designed the 2500 chassis to be the base for a new series of monoblock amplifiers where the chassis would accomplish several goals to improve performance and meet the challenges of an increasingly high production cost environment - requiring some innovative engineering: 1) help keep materials costs and, therefore, prices down; 2) do that while at the same time improving vibration control and chassis strength and stability; 3) reduce weight, which helps both with reduction of shipping costs and risks to back muscles; 4) create a sleeker, more modern aesthetic; and 5) allow for flexibility in the range of power tubes it can accommodate. Now to the “A” and “M”. Allnic uses the “M” to designate “push-pull” circuit designs, while “A” has been the designation for SET amps. In short, then, the M-2500 and the A-2500 share the same chassis, but the M-2500 is a push-pull amplifier while the A-2500 is a SET amplifier. 

 

I have owned many tube amplifier designs over the years, and historically the push-pull type has never been my favorite. Each design approach has its strengths and weaknesses.  The “power-tube flexible” M-2500, though, has hit the sweet spot between SET and typical push-pull amplifiers:  it maintains the micro detailing, textural and overall finesse across the midrange that SET designs are known for while providing the dynamics, slam factor and extended and focused bass of a push-pull amp.  Bass control with a pentode push-pull presents with optimal accuracy. I suspect the SET characteristics can be attributed to the direct-heated vacuum tube rectification. In the M-2500, the 5U4G full-wave rectifier tube replaces the semiconductor diode in the rectification circuit used in the M-3000 MKII and Allnic’s other traditional push-pull amplifiers.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

The newest amplifier to the Allnic family is the A-2500, a pure SET design. It has a completely different circuit design from the former A-311M, featuring a new interstage transformer and larger power transformers on the stronger 2500 chassis platform.  At 20W SET, these will be the go-to amplifier for any speaker of 90 dB or greater efficiency.  The A-2500 is very spacious and outstandingly musical and emotionally engaging.  And - the bass presentation in no way left me wanting.  The 845’s low-frequency robustness is on par with my favorite power tube’s, the PX25.

 

Here’s a quick summary of the differences between the M-2500 and A-2500, and of the range of tube type/output power available for each.

 

M-2500 Monoblock Amplifier (Configuration at the factory only):

 

PX25 - 1st Stage 5654, 2nd Stage 12A4, 5U4G Rectifier and PX25 x 2.  20W Continuous. Triodes in push-pull configuration.

 

300b - 1st Stage 6485, 2nd Stage 12A4, 5U4G Rectifier and 300b x 2.  30W Continuous. Triodes in push-pull configuration.

 

KT150 - 1st Stage 5654, 2nd Stage 6S4, 5U4G Rectifier and KT150 x 2.  100W Continuous. Pentodes in push-pull configuration.

 

A-2500 Monoblock Amplifier (Configuration at the factory only):

 

211 - 1st Stage 6CM7,  5R4WGA Rectifier and 211 x 1.  20W Continuous

Pure SET design.

 

845 - 1st Stage 6DR7,  5R4WGA Rectifier and 845  x 1. 20W Continuous

Pure SET design.

 

With the individual tube biasing, pairing is not necessary. Allnic circuit designs do not overdrive their tubes, and they tend to last a very long time. The M-2500 and A-2500 amps appear to retain this benefit.

 

To give you at least a rough idea of which of the “2500” monoblock amps might suit your requirements, you can find a handy calculator for amplifier power requirements for various speaker sensitivities and SPL at: 

 

https://www.crownaudio.com/en/tools/calculators#amp_power_required

 

Whatever choice you make, I am convinced you won’t be disappointed.  Both monoblock amplifiers are available with approximately a two-week lead time to delivery.  Introductory Price:  $18,000 USD.

 

If you have any questions about the M-2500, A-2500, or any Allnic product, please contact me at Info@KevalinAudio.com or 503-292-5592.  A-5000 DHT now featuring Allnic manufactured in-house 242 and HL2 has proven something special for high-efficiency speakers!

Two alternative Allnic dealers are Don Corby of Corby's Audio and David Beetles of Hammertone Audio.  Both knowledgeable consultants that focus on the appropriate solution for any system need. 

More about Line Stage Preamplifiers by Allnic!

 

Circuit design innovations by KS Park have been monumental, especially these last few years.  While Allnic as a company has grown significantly during its evolution, both the L-10,000 OTL/OCL and the L-8000 DHT preamplifiers are each hand-built only by KS PARK himself!  

 

The improved performance with Allnic’s unique 61-Step constant impedance bridge-type attenuator (CIA) commanded standardization for all line-stages currently imported into North America!  With fixed impedance at no (± 0 dB) channel unbalance, these line-stages help to eliminate the noted sweet spot for listening and preserve dynamics and imaging at any volume; an achievement rarely met in the industry.  Both the L-8000 DHT and L-10,000 OTL/OCL benefit from this feature.

 

OTL/OCL – the direct connection

 

OTL/OCL means “Output Transformer-Less” and “Output Capacitor Less.” In an OTL/OCL preamplifier, there is no coupling device between the preamplifier and the power amplifier, that is, the preamplifier’s final output tubes are directly connected to the power amplifier. Typically, an output capacitor or output transformer separates the AC music signal from the DC operating potential; if this is not done, the latter will destroy the power amplifier or loudspeakers. KS Park’s approach eliminated this risk while maintaining signal purity.

 

Coupling devices are effectively obstacles to signal transmission that add their own character (color), increase distortion, and consume small signals according to physical efficiency theory. In addition, they limit signal dynamics. Because of these adverse effects, OTL/OCL has been considered the best solution for amplifiers to maintain signal purity, demonstrating no coloration by achieving the lowest distortion possible due to the absence of coupling parts. The signal path reliably presents the information as it was intended with extremely detailed expression through the widest musical dynamics while preserving natural harmonics and subtle musical decay.

 

The L-10,000 OTL/OCL has outperformed all I have compared to in the industry.  It also has been the top seller Allnic preamplifier in Europe and proven the ENDGAME trade-up piece here in North America.
 

Line output transformer coupling

 

In tube amp circuitry, there are two coupling methods; one is capacitor coupling and the other is transformer coupling. Capacitor coupling is the traditional, low-cost method. It is somewhat stable but transfers only voltage, not wattage (i.e., not real energy). With transformer coupling, about 90% of real wattage is transferred (there is still a transformer loss of about 10% of wattage – voltage is not affected). Transformer coupling is superior to capacitor coupling. However, all the advantages of transformer coupling depend on the quality of the transformer and on the choice of tubes.

 

​Allnic Audio manufactures its own transformers and uses what it views to be the best core material: permalloy. Allnic Audio’s unprecedented, wide (16Hz ~ 75kHz, -3db), low distortion, and ultra-flexible (up to 20kHz square wave response) output transformer helps Allnic realize the ideal transformer coupled amplifier. Of course, gain tubes are also carefully selected for three critical factors for function with the permalloy output transformers: high gm, low internal resistance, and high mu. The crown jewel of Allnic’s transformer coupled preamplifiers, the L-8000 DHT (Direct Heated Triode), uses gain tubes that would be problematic for other manufacturers to incorporate in their devices because they are very susceptible to vibration. KS Park has completely overcome this issue, and while transformer coupled, the L-8000 is able to take advantage of the thermionic valve type that best preserves signal accuracy, making the L-8000 a real competitor to Allnic’s OTL/OCL preamps.


 

You can get satisfaction!

 

In my listening tests, the L-10,000 bested both the OTL/OCL L-9000 and L-8000 DHT in dynamics, with a deeper and bigger soundstage. However, all three were immersive. The L-8000 with its DHT driving tubes is exceptionally emotionally engaging with delicate layering and finer detailing, presenting stunning realism in timbre and decay, especially in the higher frequencies. The L-8000 DHT tends to make even poor recordings sound sublime; its “colourations” enhance many of the elements of live music that give us the greatest pleasure. The L-10,000 is so dynamic and accurate in presentation and clarity it can be unforgiving - a poor-quality recording can become quite annoying. Fortunately, we exist in an era of easy access to large music catalogs!

 

I remain smitten with both the L-8000 DHT and L10,000 OTL/OCL and would undoubtedly be content with either, forever. Either model will reveal new detail and a new life-like quality in familiar recordings.

The L-8500 OTL/OCL and the L-6500 with output transformer coupling have proven fantastic performers and for the price are considered the best deals to be had!