davejames
Established Member
Futher to my original post on this forum, after purchasing this amp here is my review
Monitor II Reference Series Headphone Amplifier
Purchased from: www.njc-audio.co.uk
For many years I have listened to music through my Koss electrostatic headphones but after listening to a pair of Beyer headphones I found that while my Koss headphones were very good the Beyers were better still, as naturally technology has moved on since those days, I ended up with the Beyer DT880 600ohm version, then after listening to them on a friends dedicated headphone amp I decided I needed a proper amp as the headphone out on my Technics CD player wouldn't drive them loud enough & I wasn't happy with the headphone output of my older integrated amp (Pioneer SA9500II).
I looked at all the "famous" makes but then by chance found the Monitor II amplifier built by NJC Audio, I couldnt find much information on this amplifier but after reading through the page & looking at the specifications of the amplifier it seemed very good indeed, with plenty of photos including some internal shots of the amplifiers circuit board showing the high quality components used made me more confident that this may well be an option to consider, after a few emails to NJC Audio the guy was very helpful & I found out that the amplifiers are built completely by himself, I got the impression from his email replies to me that he was a pure enthusiast, so at the end of the day I decided to take the plunge & here is my review.
The day after I placed the order a box arrived by DHL & it was the amplifier, eager to see what I had spent my money on I opened up the box to reveal an extremely nice looking piece of kit, first impressions is that this amp is really well made with nice attention to detail, but at the same time has a home made charm to it, possibly down to the fact the front panel has no legends or writing of any kind, but it certainly was not going to look out of place on my hifi shelf, with all that solid aluminium it reminded me of how they used to make amps in the good old days, it actually has similar looks to my classic "Pioneer SA9500II" integrated amp which shares a very similar thick aluminium front panel.
As we all know though, looks are not everything, it has to actually sound good, so after hooking it up to my Technics CD player I plugged my Beyer DT880/600's into the front & switched on, hmm I couldn't hear anything, no turn on pops/thumps, not even the slightest hiss when I turned the volume up, I thought to myself "is it working?" I checked the connections & the LED was on at the front of the amplifier, so I started playing a CD & the music started playing, I was amazed at how completely silent the amp was with no music being played, you would be mistaken for thinking its not plugged in if it wasn't for the LED on the front (which illuminates slowly upon switch on, I guess this is to do with the "soft start" as advertised), so far I was impressed.
After playing around with the amp for the next hour or two & listening to my favourite songs, I was very impressed with what I was hearing, everything just sounded correct to my ears, the bass was really deep but never flabby or boomy, mids are all present & the high end seems very refined & pleasant to listen to, even cranking the volume up it was never harsh or fatiguing for my ears. At the rear of the amp there is a "Gain Adjustment" switch, which has 3 positions, Low, Med & High, my 600ohm Beyers worked fine in all positions but I found with the "low" setting I had to turn the volume almost fully clockwise for normal listening level, so I figured that setting must be reserved for more sensitive lower impedance phones, Med & High were perfect on the Beyers with the volume control having a nice amount of travel.
To test the low gain setting I plugged in my Audio Technica ATH-AD500 headphones, which are 66ohms & while not reference quality like my Beyers they are extremely good at picking up any amplifier hiss because they are quite sensitive & have a rather high spike in the treble end, I tried them with the low gain setting, no hiss or hum & this setting seemed perfectly matched to these phones with plenty of volume adjustment, I then tried the medium & high settings, still dead silent on the background, although personally I would always use the low gain setting for low impedance/high sensitivity phones as you get much more adjustment on the volume control.
A day later now & I have listened to this amp a lot with various pieces of music & my first impressions that this is an extremely good quality amp seems to be confirmed more & more every time I listen to it, I am finding I can hear detail in songs that I never knew was there, the amp does seem extremely revealing & this is both its strong & weak points, on a high quality mastered CD such as "Jeff Beck - Emotion & Commotion" the amp really does shine, the dead silent background really is good with the first track & the guitar sounds very real with plenty of midrange & a quality that I just can't put into words, but the revealing nature of this amp can also be its downfall when you play a poor recording, hooking the amp up to my DAC playing a 96-128kb MP3 file, the amp picks up on the mp3 "mushyness" & reveals everything!, but I guess that is more of a problem with the poor MP3 file rather than the amp, 320kb MP3's were good but Flac was better still, providing you feed the amp with a decent signal it really does begin to sing.
After using the amp every day since it arrived I'm very happy with it but the problem is I don't have another headphone amp to compare it against, I only have the headphone output of my Technics CD player which by comparison sounds a little muffled, & the headphone out on my SA9500II equally sounds poor compared to this dedicated headphone amp, so a phone call later & I got my friend to come around here in the evening with his headphones & amplifier, he owns the Senheisser HD650 headphones & has them hooked up to his "Graham Slee - Solo SRGII", which got me interested in the whole headphone amp scene in the beginning, so I had a listen to his setup but didn't like what I was hearing, where had all the detail gone?, it was there but much lower levels than what I am used to hearing, so I plugged my DT880/600's into his amp & that was much better to me, I just wasn't used to his HD650 headphones.
We spent the rest of the evening listening to both amps using only my DT880/600's, to be honest both amps sounded quite similar at first, but it wasn't until I played a few tracks from my "Acoustic Alchemy" albums that I found the Monitor II amp revealing the slightest more detail on the acoustic guitars, the fret noise was more apparent with the Monitor II, ever so slightly recessed on the Slee, the difference was hardly noticeable but there, so I then had the idea of doing a blind test, listening for a while on each amp & then changing to the other, one amp was slightly more detailed, we were both sure that we must be listening to the Slee, but when we looked it was the Monitor II , I must point out that it was a very small difference & without an A/B comparison would most likely not be noticed at all in casual listening, but it definitely was heard by both of us, regardless of this both amps sounded superb.
I was amazed & to be honest quite pleased! my friend however was also surprised especially considering how much he had spent on that amplifier in the first place,but he made a good point that his headphone amp has a well known name, which was a point I could not argue with him on, but at the same time it was the Monitor II that just had the slightest more detail & I personally would take that over features or names etc..
The Monitor II amplifier seems to be the complete opposite of mass produced, whereby he says he makes them himself & as he clearly states "they are all made by hand & this takes a lot of time, so only a few will ever be available at any one time" or something to that effect, but knowing that each amp is made here in England by somebody that is obviously a real enthusiast, for me just adds to the charm of this amp & could explain why its such a great sounding amp with real value for money, to be honest when I saw all the specifications & the "hand made" part on his web site along with the modest asking price I thought "no way!, this is too good to be true" & I almost turned off, but maybe they are that price due to the fact he seems to make everything himself, at the end of the day I don't really care as the fact is this amp is really good value for money, sounds great & more importantly for me drives my 600ohm Beyers very well indeed, all in all this has been one of the better purchases I've made recently.
Conclusion:
Overall I have been more than suprised by how good this amplifier has turned out to be, which probably means it could hold its own against other headphone amplifiers in that class, it seems to have no problems driving low impedance phones or high impedance 600ohm phones & really seems to convey a refined sound quality which I guess is not too surprising considering the high specs & the high quality parts used inside, build quality is by far the best I have seen so far, with solid aluminium on the front panel & a hefty lump of aluminium crafted into a volume knob that really does look good quality.
To sum it all up then in a few points:
Pro's:
Here are some of the good points in brief...
Nothing is perfect & the Monitor II is no exception here...
I hope you enjoyed reading this & that it might provide a little more information on this amplifier.
Monitor II Reference Series Headphone Amplifier
Purchased from: www.njc-audio.co.uk
For many years I have listened to music through my Koss electrostatic headphones but after listening to a pair of Beyer headphones I found that while my Koss headphones were very good the Beyers were better still, as naturally technology has moved on since those days, I ended up with the Beyer DT880 600ohm version, then after listening to them on a friends dedicated headphone amp I decided I needed a proper amp as the headphone out on my Technics CD player wouldn't drive them loud enough & I wasn't happy with the headphone output of my older integrated amp (Pioneer SA9500II).
I looked at all the "famous" makes but then by chance found the Monitor II amplifier built by NJC Audio, I couldnt find much information on this amplifier but after reading through the page & looking at the specifications of the amplifier it seemed very good indeed, with plenty of photos including some internal shots of the amplifiers circuit board showing the high quality components used made me more confident that this may well be an option to consider, after a few emails to NJC Audio the guy was very helpful & I found out that the amplifiers are built completely by himself, I got the impression from his email replies to me that he was a pure enthusiast, so at the end of the day I decided to take the plunge & here is my review.
The day after I placed the order a box arrived by DHL & it was the amplifier, eager to see what I had spent my money on I opened up the box to reveal an extremely nice looking piece of kit, first impressions is that this amp is really well made with nice attention to detail, but at the same time has a home made charm to it, possibly down to the fact the front panel has no legends or writing of any kind, but it certainly was not going to look out of place on my hifi shelf, with all that solid aluminium it reminded me of how they used to make amps in the good old days, it actually has similar looks to my classic "Pioneer SA9500II" integrated amp which shares a very similar thick aluminium front panel.
As we all know though, looks are not everything, it has to actually sound good, so after hooking it up to my Technics CD player I plugged my Beyer DT880/600's into the front & switched on, hmm I couldn't hear anything, no turn on pops/thumps, not even the slightest hiss when I turned the volume up, I thought to myself "is it working?" I checked the connections & the LED was on at the front of the amplifier, so I started playing a CD & the music started playing, I was amazed at how completely silent the amp was with no music being played, you would be mistaken for thinking its not plugged in if it wasn't for the LED on the front (which illuminates slowly upon switch on, I guess this is to do with the "soft start" as advertised), so far I was impressed.
After playing around with the amp for the next hour or two & listening to my favourite songs, I was very impressed with what I was hearing, everything just sounded correct to my ears, the bass was really deep but never flabby or boomy, mids are all present & the high end seems very refined & pleasant to listen to, even cranking the volume up it was never harsh or fatiguing for my ears. At the rear of the amp there is a "Gain Adjustment" switch, which has 3 positions, Low, Med & High, my 600ohm Beyers worked fine in all positions but I found with the "low" setting I had to turn the volume almost fully clockwise for normal listening level, so I figured that setting must be reserved for more sensitive lower impedance phones, Med & High were perfect on the Beyers with the volume control having a nice amount of travel.
To test the low gain setting I plugged in my Audio Technica ATH-AD500 headphones, which are 66ohms & while not reference quality like my Beyers they are extremely good at picking up any amplifier hiss because they are quite sensitive & have a rather high spike in the treble end, I tried them with the low gain setting, no hiss or hum & this setting seemed perfectly matched to these phones with plenty of volume adjustment, I then tried the medium & high settings, still dead silent on the background, although personally I would always use the low gain setting for low impedance/high sensitivity phones as you get much more adjustment on the volume control.
A day later now & I have listened to this amp a lot with various pieces of music & my first impressions that this is an extremely good quality amp seems to be confirmed more & more every time I listen to it, I am finding I can hear detail in songs that I never knew was there, the amp does seem extremely revealing & this is both its strong & weak points, on a high quality mastered CD such as "Jeff Beck - Emotion & Commotion" the amp really does shine, the dead silent background really is good with the first track & the guitar sounds very real with plenty of midrange & a quality that I just can't put into words, but the revealing nature of this amp can also be its downfall when you play a poor recording, hooking the amp up to my DAC playing a 96-128kb MP3 file, the amp picks up on the mp3 "mushyness" & reveals everything!, but I guess that is more of a problem with the poor MP3 file rather than the amp, 320kb MP3's were good but Flac was better still, providing you feed the amp with a decent signal it really does begin to sing.
After using the amp every day since it arrived I'm very happy with it but the problem is I don't have another headphone amp to compare it against, I only have the headphone output of my Technics CD player which by comparison sounds a little muffled, & the headphone out on my SA9500II equally sounds poor compared to this dedicated headphone amp, so a phone call later & I got my friend to come around here in the evening with his headphones & amplifier, he owns the Senheisser HD650 headphones & has them hooked up to his "Graham Slee - Solo SRGII", which got me interested in the whole headphone amp scene in the beginning, so I had a listen to his setup but didn't like what I was hearing, where had all the detail gone?, it was there but much lower levels than what I am used to hearing, so I plugged my DT880/600's into his amp & that was much better to me, I just wasn't used to his HD650 headphones.
We spent the rest of the evening listening to both amps using only my DT880/600's, to be honest both amps sounded quite similar at first, but it wasn't until I played a few tracks from my "Acoustic Alchemy" albums that I found the Monitor II amp revealing the slightest more detail on the acoustic guitars, the fret noise was more apparent with the Monitor II, ever so slightly recessed on the Slee, the difference was hardly noticeable but there, so I then had the idea of doing a blind test, listening for a while on each amp & then changing to the other, one amp was slightly more detailed, we were both sure that we must be listening to the Slee, but when we looked it was the Monitor II , I must point out that it was a very small difference & without an A/B comparison would most likely not be noticed at all in casual listening, but it definitely was heard by both of us, regardless of this both amps sounded superb.
I was amazed & to be honest quite pleased! my friend however was also surprised especially considering how much he had spent on that amplifier in the first place,but he made a good point that his headphone amp has a well known name, which was a point I could not argue with him on, but at the same time it was the Monitor II that just had the slightest more detail & I personally would take that over features or names etc..
The Monitor II amplifier seems to be the complete opposite of mass produced, whereby he says he makes them himself & as he clearly states "they are all made by hand & this takes a lot of time, so only a few will ever be available at any one time" or something to that effect, but knowing that each amp is made here in England by somebody that is obviously a real enthusiast, for me just adds to the charm of this amp & could explain why its such a great sounding amp with real value for money, to be honest when I saw all the specifications & the "hand made" part on his web site along with the modest asking price I thought "no way!, this is too good to be true" & I almost turned off, but maybe they are that price due to the fact he seems to make everything himself, at the end of the day I don't really care as the fact is this amp is really good value for money, sounds great & more importantly for me drives my 600ohm Beyers very well indeed, all in all this has been one of the better purchases I've made recently.
Conclusion:
Overall I have been more than suprised by how good this amplifier has turned out to be, which probably means it could hold its own against other headphone amplifiers in that class, it seems to have no problems driving low impedance phones or high impedance 600ohm phones & really seems to convey a refined sound quality which I guess is not too surprising considering the high specs & the high quality parts used inside, build quality is by far the best I have seen so far, with solid aluminium on the front panel & a hefty lump of aluminium crafted into a volume knob that really does look good quality.
To sum it all up then in a few points:
Pro's:
Here are some of the good points in brief...
- Very good sound quality that is refined & has plenty of detail.
- Ability to drive 600ohm headphones with ample power
- Has a gain adjustment switch, useful if you own varied sensitivity phones.
- High quality parts used inside & the alps pot for example has a nice "fluid" feel.
- Solid build quality with lots & lots of aluminium, looks great & doesn't take up too much room.
- It's made here in Great Britain! by somebody who sounds like an enthusiast.
- Price!! seems too good to be true but its not! it might just turn out to be one of the rare bargains that come along from time to time.
Nothing is perfect & the Monitor II is no exception here...
- The gain adjustment switch at the back is a chrome toggle, I would have liked a little push button of some sort but that could just be me.
- The aluminium feet on the bottom seem a little overkill with the attention to detail, rubber stick on feet would have been adequate..
- The aluminium fins on top are nice looking & may aid cooling (although mine never even got warm after hours of use) could attract dust.
- While I like the fact that these are made by one person & not mass produced, maybe it might take a few weeks to get hold of one when they are sold out.
I hope you enjoyed reading this & that it might provide a little more information on this amplifier.
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