Discover why we are the best in audio repairs and upgrades.

Average Rating: 5.0 stars (based on 185 ratings)

Nu Vista 3D CR CD Player upgrade

JS Audio previously upgraded my MF A300 amp that still sounds fantastic so had John do a Stage 2 upgrade on my CD Player including new valves. Initially It sounded better and had greater detail but 4 months on and time to run in the improvement is another level. The separation of instruments, soundstage, detail is just superb, it constantly brings a big smile. Both of the items JS Audio have upgraded are now 20+ years old and would highly recommend them.

John H
Item Repaired/Updraded:Nu Vista 3D CR CD Player
February, 2024

Musical Fidelity P170 Power Amplifier

Knowing the other repairer like the Getitfixed which they destroyed this power amp when they returned it to me.
Thankfully AudioJSRepairs which is Mr John to the rescue! Mr John completely remodified and improved this power amp significantly.
I am listening now and to my surprised, the details, botom end to mid and highs expanded the sound further than the original state of this amp. I am listening to live sound the closest possible! It’s Wow!!!
This company deserve the highest score, 10 out of 10.
I will be sending more stuff in the near future to this company for either repair, upgrades or tuning my equipment.
Very highly recommended..
Thank you Mr John

Item Repaired/Updraded:P170
February, 2024


Great job. My vinyl has taken a farther step on the way to perfection. Highly recommended service, glad I decided to send my amplifier (musical fidelity A3.2cr dual mono) for repair and stage one upgrade.

Item Repaired/Updraded:Musical Fidelity A3.2 dual mono amp
February, 2024

Transformed Goldmund

John has just completed a startlingly successful repair and upgrade on my classic and much sought-after Goldmund Mimesis 9. It is now able once more to run rings around current power amp references. I have nothing but praise for his work and technical insight; you can safely leave your beloved high-end gear in his hands, confident that it will come out sound better than ever. – Jon Bower, January 2023

Jon Bower
Item Repaired/Updraded:Goldmund Mimesis 9
January, 2023

Nu Vista 800

It’s been a year now since getting my NV 08 repaired and upgraded to stage two. I’ve deliberately given the amp plenty of time to settle in as I did now want to give a “false” report.
My initial impressions were not that great to be honest . Yes , the amp certainly was better but not as much as I thought it would be .
But after giving it more time to allow the replaced components to settle in it now is certainly much much better than an original NV 08. A change of cabling (speakers & interconnects) has also contributed to the new quality.
The amp really does sing now . Still smooth but with an openess that did not exist before . Bass is deep/ strong and effortless. The slightly recessed mid band is gone and is replaced with a vivid fleshy version.
Of course it would be very interesting to compare an upgraded and standard version as relying on our memories alone may not be as accurate as we would like. Even so , I’m confident the upgraded version punches above its weight . How much above it’s weight I don’t know as I have no idea what the other integrated amps sound like in the above £10k category

Item Repaired/Updraded:Nu Vista 800
December, 2022

Musical Fidelity M6Si

Just want to share my opinion with the upgrade of my amp – Musical Fidelity M6Si.
First of all – John Sampson is a brilliant tech-guy, he knows the MF products in details and knows their weakness.
After contacting John we clarified the upgrade – 10-15 emails and I decide to make upgrade Stage 3.
It took a little bit more time but it was worth the wait.
Now my amp sounds brilliant – more natural, more powerful, the sound is amazing!
It’s a keeper for a long time!

Petar Karageorgiev
Item Repaired/Updraded:Upgraded Stage 3
October, 2022

More musical

I got in touch with John for repair of my CD player which had stopped providing an audio output and decided to go for the Stage 1 upgrade at the same time. I’m very pleased with the improvement in sound quality. Although I’ve long appreciated the Musical Fidelity sound, the combination with my PMC speakers and M6i amplifier, (which had a Stage 1 upgrade before I acquired it) sometimes lacked emotion. Following the CD player upgrade the whole system now sounds a lot more musical and involving, it’s really unleashed the potential of my amplifier and speakers.

Kevin Stephens
Item Repaired/Updraded:Musical Fidelity A5 CD player
September, 2022

Bought back to life

John is an ex MF service engineer, I worked for the company during the latter years and I’ve always been a fan of MF kit. With the sale of the company I was unsure how legacy products could be serviced and repaired.
I knew of John’s work and how highly regarded his work is seen.
I picked up an A1 from ebay, I always wanted one and found one in great condition. The volume control became noisy and the input switch became very intermittent. I contacted John and his his advise was to upgrade and service.
I said to John I wanted to retain the amplifiers warmth and musicality, the upgrade is absolutely worth the investment, I feel I now have a brand new amplifier with the Tim de P designed circuit, what a transformation. Music has come to life, organic, musically and transparent.
I can’t recommend John highly enough, he has done a fantastic job from drop off to being sent to me.
He is a genuinely nice guy who absolutely knows his stuff.

Thanks John.

Dave Waters
Item Repaired/Updraded:MF A1
September, 2022

Musical Fidelity NuVista 800

Upgrade done in an extremely professional manner. All Capacitors replaced op-amps internal cabling and speaker binding posts replaced.

The first thing I noticed was that the sound is so much smoother; sounding much more like a single ended amplifier.
The smoother sound is not at the expense of information; far from it.

I can now hear when woodblock percussion is being used; the structure of the sound is quite clear.

When listening to solo male singers, there used to be an artificial zing associated with the male voice. Now the voice sounds natural as I would expect it to sound in a live performance without amplification.
Orff: Carmina Burana the dying swan is an example of this.
Imaging is great, and dynamics have improved. The Amp also seems to work better at a lower volume quite a surprise!
This amp now punches way above its weight a very relaxing detailed sound worth every penny.

Item Repaired/Updraded:Level 2 upgrade
July, 2022

A5 CD and A5CR pre

John completed a Stage 2 upgrade on my A5 CR Pre, I was using a Croft Micro 25R pre, sounded good but presented a vague and inconsistent soundstage. John assured my that the upgraded pre would bring everything into focus.. he was SO right. Next stage was to upgrade my aging A5 CD to Stage 2, what a revelation. I also have an Akurate spec LP12 and am really not sure if I prefer listening to CD of Vinyl now. In all my years of upgrading and listening to music I have never ever said that. The A5 CD is now simply staggering. John’s advice and guidance has been invaluable through my upgrade journey (he also did a Stage 2 to my 550k power amps a couple of years ago)
Costs have gone up, but the value far out weighs the money I have spend so I am a very happy man…

Item Repaired/Updraded:Upgraded
June, 2022

Musical Fidelity Fully Balanced Pre

You switch on the amp you’ve cherished for 11 years and after a moment it turns off and you have that sinking feeling. You take it to the local highly respected repairers and you are told that the main transformer has failed and they cannot get a replacement.
You then dredge from the back of your mind JS Audio and give John a call and with a reassurance born of experience John tells you he can fix and it can be upgraded as well.
So I’ve delayed writing this review for a month or so to let it settle in now that my Musical Fidelity A1 FB Pre is repaired and upgraded. All I can say is wow….
An example of the improvement is one particular piece where the singer is singing about a gypsy market previously I could hear there was the sounds of a market hiding in the mix, but now if I focus on the market I can hear what they are selling the clarity is so clear no mush. Doesn’t stop there though
Bass more tuneful more texture more bounce.
Treble is sweeter
It’s like every part of my system has been upgraded
so a big thank you to John, he is a magician.

Alan Webb
Item Repaired/Updraded:A1 FB Pre
April, 2022

Repair and Upgrades

If like me you are wanting the right person to repair your HiFi separates you have come to the right place, John is excellent. My Quad 405-2 amp went bang so I looked at Quad service reviews, they were a bit hit and miss. My Musical fidelity A3CD player was skipping so I searched for Musical Fidelity repair and found John with 100% 5 star reviews. I phoned John up and just talked about my requirements, there was no hard sell or pressure at all. I then decided to get John to fix the amp and CD player but also to do a stage 1 upgrade on my A3CD, Quad 34 control unit and Quad 405-2 amp. The amp had blown one of the mid/bass drive unit voice coils on my Spendor SP1 speakers and John recommended Wilmslow Audio who replaced the voice coils on both mid/bass units, recapped the crossovers and rewired the speakers with new binding posts. So, how does the system sound? In a word, unbelievable. Everything is richer, deeper and more detailed, it really is like having a brand new CD collection. On great recordings I feel like I’m in the room with the musicians, the sound is so life like. Thank you John for doing a brilliant job on my separates, the sound is high end, just as you said it would be!

Robin Taylor
Item Repaired/Updraded:Musical Fidelity A3CD, Quad 34, Quad 405-2
March, 2022

Stage 3 – Is there no limit?

So had to take my kW500 for a check as I had clumsily shorted an input terminal (with the volume still up!) Asked John if he could do the stage three upgrade which includes a new Alps pot and upgraded capacitors, well it just gets better and better!! The sound stage is even more defined, the separation is phenomenal. If you’ve got a kW500 then let John at it and be prepared for a very pleasing outcome! As ever Genius!!

Kevin Wood
Item Repaired/Updraded:KW500
March, 2022

Spectacular Delivered

Having had my MF A3 Dual Mono Pre amplifier upgraded in 2019 by John the difference in sound quality was immediately noticeable and improved even more over time. In the search of sound perfection John had also suggested at the time of upgrading my MF A3 power amp to increase the quality even more. The word “spectacular” was sown and stuck with me… move on and 2 years later… I bit the bullet and went for the stage 2 upgrade. Coupled with Monitor Audio Gold reference speakers I just cannot believe the depth of sound, the bass and tone across all the ranges is incredible, I have purposely waited three months before writing and again over time the sound just continues to improve, and is way beyond my expectations. .JS Audio truly have delivered “Spectacular” in every way. Thank you so much.

Stuart Duff
Item Repaired/Updraded:Musical Fidelity A3 Dual mono power amp
March, 2022

XA -200R repair & upgrade

Musical Fidelity XA-200R upgrade

It’s been roughly 3 weeks since I delivered by beloved but aged XA-200R down to JS Audio. I traveled back down to collect my amplifier, on the day after the very strong winds, that caused so much destruction around various parts of the uk. Little did I know my XA-200R was brewing up a storm of its own. When I got home and reconnected my amplifier I thought I would leave it fired up and go and make myself a coffee while it warmed up. The first few things I noticed while listening was a faster, deeper bass underpinning the other parts of the frequency range. Drums and bass guitar had another level of grip, speed and power that was not there before. All this was done while still sounding smooth and detailed. Instruments have taken on another level of clarity and separation. The image depth has now become so deep and wide, I am finding myself looking around the room to see how the percussionist, has some how managed to sneak into my house. The mid to high end has also emerged with a new lease of life, seeming to sound louder and more enriched with musical detail. I am not sure what John has done with my old amplifier, but the new addition is far better than the old. It’s almost like he’s given my amp a big sprinkling of magic fairy dust. My biggest problem now is what to upgrade next. X-Ray CD or my XA-200 power amps. Any help will be much appreciated.

This is the first of two upgrade reviews I am going to do. This one has been a next day review. My next will be either two or three months from now to see if the improvements continue.

John, thanks for the fantastic work you’ve done regarding my XA-200R amplifier.

Item Repaired/Updraded:XA-200R upgrade
February, 2022

Wow – Musicality discovered

It was by complete chance that I discovered John. I didn’t own MF gear, but heard of John through my brother. My Cyrus pre/power amps just weren’t doing it for me. I didn’t have any gear to upgrade, but instead called John for advice on how to proceed. John was absolutely fantastic and advised on the best way forward for my budget.

After some searching I now have an XP100 pre amp and an a3cr power amp. Both have been expertly upgraded by John and are a mind-blowingly good combination. The upgraded MF pre/power combo cost half as much as my old Cyrus pre/power and completely embarrasses the Cyrus. It’s frankly not even close – the JS upgraded MF amps have introduced me to a quality of music that far surpasses the Cyrus kit.

It’s fair to say the the XP100/a3cr improve every aspect of sound quality… Big, wide and deep soundstage and a realism I never thought possible with my budget. The music is so organic and natural. I’ve been into music and hifi for nearly 30 years and I can honestly say these MF amps are the first time I’ve stopped listening to my HIFI! The musicality is incredibly good and I just find myself getting lost in the music! That is some achievement – Thank you John!

Jason Darke
Item Repaired/Updraded:MF XP100 Pre/a3cr Power
January, 2022

MF A100 – upgrade MAGIC!

As I wrote to John soon after getting my refurbished & upgraded Musical Fidelity A100 back earlier in the year, it was magical, but now it is exceptionally so! It runs quietly & so much cooler. It was hot & noisy 32 years ago, so a huge improvement! The sound is incredible & I have never bothered to turn my REL subwoofer back on. It is like reviewing a new collection of music with everything sounding more musical & exciting. Friends are dumbfounded at the sound coming out of my small but trusty Quad 77-11L speakers set on custom wall brackets. I could always drag my transmission line TDLs out of the loft, but quite unnecessary. Happy times are here! Thanks John.

Chris Tween
Item Repaired/Updraded:Musical Fidelity A100
October, 2021

Musical Fidelity Amp Upgrade

V Old , but much loved Amp & Pre amp. When the Phono Chanel went , I knew it was a time for repair or replace.
I chose repair / Upgrade and am very glad I did.
Amazing Clarity – smooth smooth sound with loads of definition.
I am now re-listening to my entire music collection to pick up on all the bits I was missing before. Txs Andy

Andy Burdon
Item Repaired/Updraded:3A & P140
September, 2021

Musical Fidelity A3 CD Repair & Upgrade

My venerable and much-loved A3 CD had become increasingly fussy about which CDs it would play and, having had the player for about 20 years, I knew it was time it received some attention.

I had heard about John in one of the hi-fi magazines, so contacted him about the problem. We had aa lovely chat, and John was able to confirm he could repair my player and, if I wished, upgrade the performance.

So, I took the plunge and went for the upgrade. And I’m absolutely delighted I did! It really was like hearing my music collection for the first time.

I couldn’t be more delighted – well, perhaps I’m slightly narked that my A3 CD / A3 24 DAC source now sound better than my turntable!!

Next-up is my equally venerable and equally much-loved X-A2, which will be on its way to John for the upgrade, shortly.

In short, John really is the only person you should be entrusting your Musical Fidelity gear to. He’s the expert – just read all of the reviews!!

Shaun Hourston-Wells
Item Repaired/Updraded:Musical Fidelity A3 CD Player
August, 2021

MF A3 integrated upgrade

John is one of the gems of the hifi world! His knowledge of electronics, upgrades and the general industry is just staggering; he’s willing to share it too, always keen for a good chat about your system and upgrade potential, a wealth of expertise and great advice. Not only has he transformed my A3 into a genuinely high end amplifier, with the performance of an amp costing several times the purchase price, he’s also offered hugely effective advice and tips on other areas of my system including cabling and tweaks.
Basically that great phenomenon during listening whereby the system just disappears and jaws drop in disbelief at the realism of a great recording, now occurs far more regularly. Without a doubt the best upgrade I’ve made so far. When can JS upgrade the rest of my system!!? Thanks very much John.

Sam Darke
Item Repaired/Updraded:MF A3
July, 2021

MF KW SACD player

My KW SACD player developed a fault where it wouldn’t read the CD’s, then the CD tray stopped ejecting altogether. I phoned John and his reassuring knowledge of the player persuaded me to send it of to him to be fixed.
I’m only writing this review 18 months after having got it back due to a small daughter who would have pressed and prodded it in the existing equipment support, now it sits in a child resistant rack.
John has performed miracles on my machine, what was already a stupendous player is now in another league, the sounds have filled out in the highs, mids and bass. I’m completely blown away by what he’s achieved. I also have an Audiolab CDT6000 transport and a RME ADI2 DAC which I can compare it to, they are no slouches either, all running through a Karan Accoustics KAI 180 amp and Anthony Gallo REF 3 speakers, John is a magican, no hesitation in recommending his services. Brilliant Brilliant Brilliant.
One very very satisfied customer.

Mark Rampton
Item Repaired/Updraded:KW SACD player
July, 2021


In-short I am very impressed and completely satisfied with the difference the upgrade has made. John has simply worked wonders. The depth, detail and base especially, have improved significantly, to the point that familiar tracks physically made me glow and smile

Item Repaired/Updraded:UPGRADE
July, 2021

Musical Fidelity A5 Amp. A5 cd player

I upgraded my Musical Fidelity A5 integrated and A5 cd player! First and foremost, to say that John is a genius is an understatement. He knows what he does and is an expert at it. I have been an audiophile for 36 odd years. During this period, I have had loads of gear as it is with most audiophiles.
I cannot name all the various brands I have had during this period, I have always wanted better and never knew when to stop, Long story short, somehow trying to explore the next level of my unending passion and hobby I came across JS Audio, it took me a couple of months before contacting John and was very surprised by his level of audio knowledge and understanding, the thing that struck me most was that he was not selling a product or service but genuinely looking to help you achieve the best you are looking for in your hifi journey.
I had hours of telephone conversations with him and finally decided to upgrade my Musical fidelity A5 integrated, it took sometime for it to arrive back due to Covid 19. When I received the Amp, a few things were very evident, the noise floor was amazingly quiet, the dynamics and soundstage are wider, vocals and voices have amazing clarity like never before, instruments sounded real and live-like but I have to be honest, I still wanted more, I changed speakers, cables, interconnects and powercords.
I called John and he explained to me that I just have to allow the components to settle in with time, I decided to send my A5 cd player for an upgrade as well and when I received the CD player back and plugged it in, wow, suddenly everything changed, I cannot describe it but its just only a few days that I got the cd player back but I thought I write this review now. Maybe after one month I will have to write another review. I had a stage 2 upgrade on the Amp and a stage 1 on the CD player.
If all those hundreds of reviews won’t convince you for an upgrade just give it a try and you will be pleasantly surprised. I have to also say that John is a very nice gentleman as well, I travelled a long way to meet up with him personally.
John also gave me some advice and tips on speaker selection and that also helped me a lot in my last speaker purchase. I am enjoying my music now and looking to send my old amp of the 90’s which I have cherished for many years for an upgrade soon. I don’t know what de does and how he does it but something is just simply right with what he does. The problem now is that I want to listen to all my over 1000 cd’s over again. Lastly, be warned that very good recordings will be excellent and poor recordings will be exposed sadly, that’s my experience as I go through my CD’s over again.

Edward A
Item Repaired/Updraded:Upgraded
May, 2021

Mightily Impressive

I’ve now had my Musical Fidelity M6 PRE amplifier for a week after a stage 2 upgrade carried out by Mr John Sampson. And I’m mightily impressed with the results. The sonic presentation is more cohesive ‚Äì and better integrated ‚Äì like a jigsaw with all the pieces in their rightful place.
In terms of details the bass is definitely tighter with a more rounded tone. Mids are a tad more forward with vocals better articulated – a delight for lovers of the human voice like myself. The changes to the highs are less obvious, more subtle but I can detect no harshness or tendency towards the brittle – always the bane of the top end.
All in all Mr Sampson’s work has really hit the spot. Don’t hesitate if you’re thinking of an upgrade to a bit of your kit ‚Äì you’ll leave your treasured hi fi in the best of hands. I shall certainly be returning to him with my other Musical Fidelity pieces in the future.

John Ridley
Item Repaired/Updraded:Musical Fidelity M6 PRE
May, 2021

M3 Nu Vista Amp

Thanks John. The amp sounds so much better now. And I appreciate too your recommendation for the turntable and for upgrading the phono stage in preparation. Now enjoying all my old vinyl – puts CDs to shame.

Nick Burke
Item Repaired/Updraded:Serviced
April, 2021