Musical Fidelity A1 Class A Integrated Amplifier 25W/8Ohms Black - Musical Fidelity
|
|
Information
Musical Fidelity A1
In Hi-Fi, the Musical Fidelity A1 has become one of the most classic designs – inside and out. First released back in 1985, it quickly made waves for being an absolute beast when it came down to driving some of the most difficult speakers of that time, even though it was actually a rather low powered integrated amplifier. But: it was all done in pure Class A with excellent and expertly laid out discrete symmetrical circuitry topology and using only highest quality components. The A1 showed people that there was more to amplifiers than just high power.
Based on its huge success, the A1 has gone through multiple reissues and new versions over the years.
Now for 2023, for the first time since its initial release we have actually kept all specifications, the appearance and circuits of the 1985 rendition for those who missed out the first time. With an updated transformer, power supplies and modern low noise components we’ve revitalized the formula and are proud to reintroduce the fresh original – three decades later.
Technical Talk
The A1 is built around a completely discrete and symmetrical Class A topology. It‘s able to output 25W of pure Class A power @ 8 ohms load with 25A of maximum output. While the numbers here might seem rather low, the ability for the output stage to drive difficult speakers is a small miracle in itself. The amp design being dynamic class A, and if Class A standing current is exceeded, it will automatically allow more. It therefore “slides” (NOT “switches”) smoothly into class B style operation, temporarily allowing the further current draw needed.
Power Supply
The new A1 has received an updated transformer from shared (1985 original) to more efficient “dual mono split rail” windings. The amp stages are supplied by fully independent left and right power supplies for better power handling and stereo imaging and each power amplifier now has double supply capacity resulting in reduced ripple and noise.
The transformer‘s noise and heat dissipation are reduced due to better efficiency and updated components. The main supplies are filtered for better regulation and reduced switch on surge.
Preamplifier
The low noise preamplifier circuitry is the same as the original 1985 design and, as we have highlighted above, greatly benefits from the improved, fully smoothed and regulated power supplies.
Among the discernible alterations, one that immediately catches the eye is the addition of a new „direct“ switch at the preamp stage. With this switch you can totally bypass the gain block before the volume control, resulting in roughly 10dB less gain. This feature proves particularly advantageous when working with modern or high-output digital sources, enabling fine tuning the range of your volume potentiometer and accommodating sensitive loudspeakers.
Furthermore, a notable upgrade has been made to the volume potentiometer itself, now replaced by a premium ALPS RK series potentiometer. This high-quality component ensures superior performance and enhanced precision. Additionally, the potentiometer is now motorized, granting you the convenience of adjusting the volume from the comfort of your couch, courtesy of the new included remote control.
 |
 |
Phono Stage
The A1 employs a discrete current-mode input stage for lowest noise amplification of MC and MM cartridges. A low noise current to voltage conversion stage is used for further amplification and RIAA equalization. Automatic input impedance matching for the selected MC input, along with increased gain increases the versatility of the A1‘s phono stage.
The return of a true Hi-Fi classic
The A1 has one secret. This secret is simple: it makes music. It sounds sweet and fluid and creates a beautiful atmosphere around natural instruments. Especially in small to mid-sized rooms, carefully set up with a pair of great two-way speakers. It is not a powerhouse, but music lovers will cherish its abilities.
It‘s also not a product that you‘ll want to hide. A perfect example of form follows function. The oversized heatsinks define the A1‘s look, but they are essential for its operation. Truly unique, from the outside and inside.
The A1 has a sweet, warm, full and exciting sound. No harshness. No grain. Just pure music. It doesn‘t get muddy, and despite its lower power, drives difficult speakers with ease. It remains clean right up to its power limit. To hear what the A1 does is to hear what Hi-Fi is supposed to do: it makes music, pure and simple.
The A1 through time - Improvements to the original
- Updated transformer to more efficient “dual mono split rail” windings
- High quality and updated ALPS RK series potentiometer as volume control
- IR remote control added for volume
- Gain block before volume control totally by passable using “direct” switch (-10dB)
- All transistors including output devices are carefully selected modern equivalents
- All capacitors in signal path are polypropylene (PP) type
- Resistors are modern low noise metal film types
- Care and attention made to not change any component specification from original but to update them to modern equivalent with long lifespan
- Layout faithfully follows original within circuit sections on circuit board
- Circuit sections better laid out, in particular the separate supplies and power amplifiers
- Phono stage and preamplifier improved for less noise and hum
Features
The A1 in Brief
- 25W Pure Class A power @ 8 Ohm
- Discrete symmetrical topology
- Planar Audio transistors with 25A maximum output
- Dynamic class A, slides (NOT switches) smoothly into Class B, allowing more current as needed
- Therefore drives difficult speakers with no problems
- Updated transformer to “dual mono split rail” windings
- Fully independent left and right power supplies
- Each power amplifier now has double supply capacity
- Transformer noise and heat dissipation reduced
- Filtered main supplies
- Gain block before volume control totally bypassable using “direct” switch
- High quality and updated ALPS RK series potentiometer
- Low noise TL071 JFET preamplifier circuitry
- Discrete current-mode MM/MC phono input stage
- Low noise current to voltage converter for further amplification and RIAA equalisation
- Automatic input impedance matching (1K nominal) for MC along with increased gain
- Original (1985) A1 appearance and circuits with modern improvements
- Remote control added for volume
- Modern updated low noise components
Specifications
A1 - Specifications
Amplifier
- Power: 25 Watts per channel into 8 Ohms
- Voltage: 42.5 Volts peak to peak
- Current: 25 Amps peak to peak
- Damping Factor: 150
- Gain (volume max): 32dB (Direct Mode), 42dB (Normal Mode)
- Output devices: 2 per channel
- Signal / noise ratio: 82dB
- Channel separation: 85dB
- Frequency response: + 0, –1dB, 10Hz to 40 kHz
- Line level sensitivity: 300mV rms nominal, 8V rms max
- Line level inputs impedance: 25k Ohms
- Tape Out impedance: 220 Ohms
- Pre Out impedance: 100 Ohms
Phono Preamp
- Phono RIAA response: +/- 1dB
- MM sensitivity: 5mV nominal
- MM capacitance / impedance / gain: 100pF / 50k Ohms / 40dB
- MM signal / noise ratio: 75dB
- MC sensitivity: 450μV nominal
- MC impedance / gain: 1k Ohm / 60dB
- MC signal / noise ratio: 70dB
Inputs
- 1x phono RCA MM/MC, 5x line RCA
Outputs
- 1 x line level RCA fix TAPE OUT
- 1 x line level RCA var PRE OUT
- 1 x 4mm banana/binding posts SPEAKER OUT
General Information
- Dimensions (WxHxD): 440 x 68.3 x 283.3 mm
- Main voltages: 230V/115V Internally set or 100V optional
- Max. Consumption: 130W, 0W in standby (=Power Switch OFF)
- Weight: 10.5kg
Reviews
 |
"This Class A unit picks up where its predecessor left off – notable for an organic, almost tube-like presentation." EISA 08/2024 |
 |
"A delicious sounding full Class A integrated amplifier that’s way more practical than before." editors - stereonet 01/2024 |
 |
"It is true ‘affordable esoterica’, then – offering performance in some respects that’s hard to beat at three, four or maybe five times the price." David Price - stereonet 09/2023 |
 |
"The musical Fidelity A1 it really delivers. The 25 watt per Channel A1 sounds like it has more drive and more poise. An arresting musical presence. It creates a listening experience that prioritizes dynamic drive." Darko 10/2024 |
 |
"It now sonically delivers everything you could expect from a modestly sized Class A amplifier: Detailed liquid smooth harmonically saturated mid-range good bass, top end that‘s extended and refined. " A British Audiophile 09/2023 |
 |
"I love the look, I love the feel, I love the sound, I love the weight that it brings to music. This thing sounds like it‘s got some serious balls – a knockout!" " The Audiophiliac 10/2023 |
 |
"I want one I really really want one. the music is always composed and clean and clear in the main and full of energy and vivacity that keeps you infused as The Listener." " Pursuit Perfect System 01/2024 |
 |
"Together with a bit of mellowness and smooth midrange handling, it’s suited to both easy listening and more ‘critical’ sessions. It’s reasonable to call the A1 a very versatile overperformer." Jamie Biesemans - Hi-Fi News 01/2024 |
 |
"The A1 remains an absurdly talented amp. Exceptionally unmechanical sense to the power delivery. The performance has that same compelling naturalness as the rest of the amp." Ed Selley - hifi+ 02/2024 |
 |
"It feels like a powerhouse. The midband is the star of the show, being really open and revealing.The A1 sounds very silky up top. A great sounding design at a surprisingly affordable price." Nick Tate - HI-FIChoice 02/2024 |
 |
"There’s still something about the Musical Fidelity that takes you aback. It’s a combination of truly outstanding tonality, that absolute lack of mechanical process and imaging that creates something rather special. This stereo image is truly spectacular." Ed Selley - avforums 11/2023 |
 |
"A timeless classic, as good as it was, but better. The most refined, rich, human-sounding phono stages ever included in a humbly priced integrated. The A1 has that supersaturated toaster-glowing „electrostatic midrange“. Sound was still rich and vital, with a level of tone and tempo truthfulness that revealed the invention and preserved the joyful spirit." Herb Reichert - stereophile 09/2024 |
 |
"The A1 elicited an emotional response, as good audio does. An ideal balance between control of the bass and freedom for it to breathe. Treble was typically Class A, silky but not overly smooth. The midrange was just gorgeous." Phil Wright - the ear 07/2024 |
 |
"The A1 never stopped short when it came to a convincing balance from top to bottom immediately asserted itself with a lively, dynamic sound.A1 can get your feet tapping and has the ability to image correctly, and place everything into a relatively large and airy soundstage. One of the most intriguing and talented integrated amplifiers for the money." Marc Phillips - parttimeaudiophile 08/2024 |
 |
"The A1 doesn‘t hesitate to give me the straight goods. Expressive and fluid.The stereo imaging is stable and wide enough to extend beyond the speakers.Piano is superbly reproduced, and I don‘t miss a single micro-detail of the percussion. This little integrated knows how to push hard in the bass." Michel Dallaire - Tendances 06/2024 |
 |
"It‘s a gift we‘ve been waiting for. It certainly sings. Everything is full with unexpected depth. No problem for this A1 revisited, a total success that shows „technology of yesteryear“ is far from obsolete." Editors - Diapason 02/2024 |
 |
"The warmth that envelops the amplifier after just a few minutes of listening radiates instantly into the music. A perfectly perceptible physical reality is attested. There‘s no harshness or acidity to spoil the musical reproduction." Editors - Classica 02/2024 |
 |
"This is how music sounds, not hi-fi – The new A1 enchanted with an incredibly coherent, colourful and natural sound of high cohesion for the money, remi- niscent of good tube amplifiers." Marius Dittert - audio-stereoplay 07/2023 |
 |
"We are overwhelmed. There it is again, the spirit of the first A1 from the 1980s – lots of sound, lots of heart, deliberately also for smaller budgets. This amplifier is capable of something that I have never experienced with much more expensive amplifiers: so much control, so much sound color, so much lively music." Andreas Günther - LowBeats 02/2024 |
 |
"The creamy colorful music reproduction is of outstanding quality, extremely delicate and fine, of rarely heard detail and expressiveness. The stage is very well illuminated and layered in depth." Tom Frantzen - Stereo 09/2023 |
 |
"In terms of sound, it is completely musical, full-bodied and pleasing to the ear. Organic is perhaps the best word for it." Thomas Kirsche - Audio Test 01/2024 |
 |
"Musical Fidelity‘s A1 storms forward with powerful verve and intense colour. Everything has an extra portion of umami. The fun factor is much more pronounced. The Musical Fidelity A1 and the LS 3/5A are simply made for each other." André Schwerdt - i-fidelity 04/2024 |
 |
"The amplifier now sounds even bigger and more spacious. But the charm of the original remains untouched." Thomas Kirsche - Like Hifi 10/2024 |
 |
"I have listened to the Musical Fidelity A1 with great pleasure. A wonderful amplifier for the price that pairs with both the LS3/5A and the LS5/9. Sufficient power, nicely transparent, slightly warm bass, clear without being too bright. An amplifier made for enjoying music." RENÉ VAN ES - HiFi.NL 01/2024 |
 |
"The 2023 model doggedly sticks to the original design brief and still supplies a smooth, warm and detailed sound, exactly what you’d expect from a good Class A amp." Marc Sparrow - Forbes 08/2023 |
 |
"A-class circuitry High quality, MC/MM phono input, Stronger than the watts would suggest, Silky sound " Kari Nevalainen - Hifimaailma 12/2023 |
 |
"The only thing that matters is how the amplifier performs, and that‘s just great! Its sound turns established trends on their head, breaks down categories and destroys prejudices. It has my highest recommendation!" Viktor Kubal - High&Style 09/2023 |
 |
"This is an acoustic antidepressant. You can hear the difference in implementation, acoustics, detail, and tonal balance; everything is dipped in subtle, aromatic sauce, improving consistency and reducing unpleasant accents and raids." editors - Audio.com.pl 09/2023 |
 |
"This set stops us with creamy-sounding music, where we forget about audio. it plays music for us and it does so that the process of listening to it becomes a pleasure. His greatest asset is to focus on the color of the sound, which is always under its control." editors - Audio Idiom 10/2023 |
 |
"There is something magical about it. What comes to the forefront is a huge emotional charge wrapped in a capsule woven with softer sounds." Waldemar Nowak - InfoAudio.pl 11/2023 |
Associated Items
View your shopping basket or Browse other items in Musical Fidelity.
