Moor Amps Angel-4 MkII power amplifier
Picture it. It had been a long, exhausting day traipsing around the Deluxe show in Whittlebury earlier this year, when I was drawn into one of the smaller rooms by the sweet sounds emanating from within. It was not the biggest room and what was on dem was not the most expensive equipment in the show, not by a long way, but what I heard there was one of the very best sounds of the day, proving that sometimes less is more. Or in this case, Moor is more. It made me curious to get better acquainted with the brand and what it had to offer.
The brand in question was Moor Amps and they were demonstrating their brand new, revised Angel-4 MkII power amplifier. I knew that the editor was very impressed with their Angel-6 when he reviewed it in 2020 and I had no hesitation in expressing my enthusiasm to review the MkII version of the Angel-4 there and then. Moor Amps has been producing quality electronics from its base in Dorset since 2019 and was founded by electronics hardware and software engineer Tim Narramore and his partner Ruth, both are driven by a lifelong passion for music and engineering.
The name Moor references not only Dartmoor and their West Country roots and his own surname, but also their philosophy of ‘More Amps’ – which is all about current capability, control and headroom.
Talking to designer Tim Narramore about the design, he told me that one of the key factors enabling them to improve the Angel-4 was the work they did to improve the performance and sound of their Mana DAC, which then allowed them to significantly improve the performance of the Angel-4 power amp.
Tim explained that while the circuit board and power amp circuit design is much the same as in the original Angel-4, the major upgrade has been to use a ‘three-island’ power supply like that is used in the more powerful Angel-6 (150W compared with Angel-4’s 75W). The new three-island power supply in the Angel-4 MkII has three times as many capacitors as a conventional power supply and therefor significantly increased capacitance, Moor have also improved the quality of the power supply to each amplifier module by lowering the supply impedance.
The three-island power supply uses a conventional reservoir capacitor stage to deal with current pulses from the large transformer, but this is supplemented by two high-capacity filtering stages and regulation to ensure a very pure DC supply.
In the Angel-4 MkII, track lengths have been reduced and routing improved, with the power supply placed as close to the output transistors as possible to keep series resistance low. This is said to improve linearity and reduce intermodulation distortion.
And keeping intermodulation distortion low is a key goal for Tim rather than fixating on THD, which he doesn’t feel compromises sound quality as badly. Witness many great-sounding valve amps that have high THD. He has also kept feedback to a minimum in his design and says that getting the power supply as good as possible was critical as he couldn’t rely on feedback to correct any problems in that area. There are virtually no capacitors in the signal path, just one on the input. All of these changes, says Tim, have resulted in better dynamics and given the amp tighter control of the speakers.
The Angel-4 MkII comes with Moor’s usual five-year warranty and the good news for existing Angel-4 owners is that their amps can be fully upgraded to MkII spec by a return-to-factory upgrade service for £1,250. I am also told that a MkII version of the Angel-6 is due later this year.
Laying the groundwork
A power amplifier selling for around £8,000 obviously deserves to be evaluated in a system of appropriate quality, and because my system does not comprise a separate preamplifier, I needed to find something suitable. My friends at Home Media in Maidstone came to the rescue and loaned me a Chord Electronics Ultima 3 preamp. I am familiar with the excellent Ultima integrated amp and was sure the Ultima 3 preamp would fit the bill nicely.
The rest of the system was my usual current home system with Audio Note TT3 turntable with Arm Two and Io1 cartridge and Fyne Vintage 10 speakers with SuperTrax super-tweeters. CDs were played on an Audio Note CDT Five transport with DAC 5 Special. Because the Ultima 3 preamp has no phono input, I also pressed into play the excellent SPL Phonos Duo phono stage.
This worked well for me as, to all intents and purposes, it was just the amplification that changed in what is my usual home system and so it would give me a very good idea of the Angel-4 MkII’s contribution to the overall sound.
Can I have some Moor?
I have to say that right from the first few notes and bars, I felt totally at ease with the Moor Amps Angel-4 MkII. It did not impose itself upon the sound with any undue forwardness, brashness of fireworks, it just presented the music in a way that enabled me to appreciate what and how the musicians were playing and how their individual contributions gelled together. The Angel-4 MkII was dynamic without harshness, rhythmically taut, involving and revealing of the playing style and voice of my favourite guitar and sax players.
Never more so than when I played guitar legend Larry Carlton’s cover of The Doobies’ Minute by Minute on his Discovery album. Here, the deep, sinuous and fast-paced bass line was conveyed with great weight, control and fluidity. Carlton’s guitar was beautifully voiced and I could hear the nuances of his play and technique. Percussion was detailed, dynamic and never splashy.
A favourite track at the moment is the cover of The Isley Brothers’ It’s Your Thing on bass player Christian McBride’s Conversations with Christian album. This is a simple duet with vocalist Dee Dee Bridgewater and the Angel-4 MkII captured the fun and spontaneity of the performance. McBride’s bass was full, weighty and agile with good control on fast runs of notes and real grip on the lowest notes, with excellent leading-edge bite. You could also hear the thwack when he slapped the bass and the twang when strings resonated. Bridgewater’s vocals were also packed with emotion and attitude, while the Moor conveyed the sense of fun very well. Never did it make her voice sound forced or unnatural.
One track where the lead vocal can often get screechy and overbearing is Night & Day from Jon Allen’s excellent Deep River album. I am happy to report that this was not the case on the Angel-4 MkII, which conveyed the power and emotion in his voice without making it shout. The guitar on the intro also had great note shape and leading edge, and the double-beat kick drum that pumps the track along was tight and well defined. Cymbals meanwhile were delicate and detailed, and the Hammond organ backing was well defined and easy to pick out.
Another vocal it’s tricky to get right is Gregory Porter, and it was his song Hey Laura from the Liquid Spirit album that I spun up next. I was very pleased with the Angel-4 MkII’s ability to convey the unique character and phrasing of his vocals, it captures the weight and power in the lower registers without boominess or thickening. Piano too was open and well voiced and the track moved well.
Moor musical
Rhythmic solidity and energy are a strong point of the Angel-4 MkII and that was ably demonstrated on the super-fast No One Emotion by George Benson. The track sped along unimpeded on the Moor and the various layers of this complex arrangement were well conveyed from the Rhodes piano to the string and horn sections. The bass line was also tight and agile.
The Moor Amps Angel-4 MkII is an extremely capable amplifier. It has bags of power and simply lays the music out in front of you to be enjoyed, without distraction, embellishment or omission. Its sound is detailed, dynamic, musically coherent and compelling and simply immerses you in the music and lets you hear what’s being played. What more (Moor?) could you ask for?
Pros
Powerful, controlled and highly dynamic sound
Excellent bass grip, weight and agility
Natural, expressive vocal reproduction
Detailed without sounding harsh or analytical
Strong rhythmic drive and musical coherence
Reveals instrumental textures and playing nuances
Generous power reserves and speaker control
Five-year warranty and upgrade path for existing owners
Cons
Premium price for a stereo power amplifier
Requires a high-quality preamplifier to perform at its best
Feature set is deliberately minimalist
Competition is strong at this price point