Avondale Audio

Avondale Audio Headed by Les Wolstenholme, designers and manufacturers of solid state audio amplifiers and power supplies.

Avondale Audio is a long established British company of Audio Engineers Based in West Yorkshire England who, for almost 50 years, have specialised in upgrades and conversions to several well known brands - in particular, the products of Naim Audio. Efforts are directly exclusively towards creating innovative audiophile designs and construction methods, towards building 'the most affordable, serio

us audiophile amplifiers you can get for your money'. Avondale Audio supports the DIY audio community, and make many of its key designs and modules available to novice and experienced audio builders.

16/05/2026

Bonus Weekend Wittering

On the subject of regulators:

Many of the commercial offerings today emply a closed loop feedback system or error correction. Simply put, there has to be an error before there can be a correction - no such thing as 'clairvoyance' when it comes to error correction.

Over many years of building and bodging, many designs have crossed my desk only to leave a sense of lacking when it comes to that sparkle we instinctively know as music. Note here: that instinct is built in to us all but we tend to endorse lesser degrees of musical reality under the widely accepted belief - that's all there is.

Moving on, the shunt regulated supply seems capable of addressing most of our reservations and exposure to a piece of kit supplied by a shunt universally provokes a positive response.

However, not content with the apparent value of the shunt, I decided to emply some inspirational thinking I'd first used with my 1980s design for Sugden in their AU51C pre-amp. I introduced a series of RL - Resistance + Inductors across the DC rails after the regs.

Now, I'm aware that many a manufacturer of capacitors is valiantly trying to outdo the competition when it comes to transient delivery. Lower ESR figures tell only a fraction of the story and it's my stance that caps alone will not do the business we all thought they would. Looking at the circuit topology of a capacitor, we find resistance, capacitance and inductance in variable quantities so the question is: what portion of that melange does the business as far is music is concerned.? For example, does the cap contain energy or does it release it when directed to do so and in the quantities demanded by the musical signal.?

Some time ago, I pondered this matter and devised a way of extracting the favourable elements of a capacitor's performance firstly by adding more capacitance - slowed the leading edges abysmally so abandoned that direction. Additional resistance came to nought therefore suffered the same fate. Then, swimming against against the traditional stream, introducing inductance lit the way.

Allow me to share with you here: A premium quality of an inductor, amonst many others, is that it does not like to have the voltage across it changed so once charged, it remains in some sense, a rock solid reservoir of a small amount of DC charge. Delivery of its accumulated energy when demanded is infinitely faster than any capacitor ever made enabling a reaction time off the clock. Introducing an inductor or in my case, a varying series of of 'lumped' inductors across a regulated supply line, levels the sonic playing field and the flow of music begins to take on a sense of immediacy and solidity otherwise not available by any combination of regulators or by banks of capacitance.

Here I apologise for being unable to cite models and calculations because, as far as I know, this is uncharted territory so becomes almost improbable to the engineers and designers looking in.

I offer this as 'seed' thoughts for the moment in the hope of encouraging further experiments and investigation.

Thanks for joing me in these weekend thoughts and as always, please share your own thoughts as they arise.

16/05/2026

Weekend Wittering:

I'm sure most of us have wondered why amplifiers exhibit differing sound qualities in varying systems and cabling. To date, I've yet to see any in-depth discussion as to why - the case being left hanging so to speak, vague references being mainly concerned about cables and other external influences on the performance of an amplifier rather than going to the root of the problem. Perhaps the root of the problem is largely misunderstood so dear readers, read on.

Well, many seed thoughts have resulted in much experimentation here and I have to suggest that although amplifier topology and strategic layout of the circuits may have claimed many audible sonic benefits, the root of this phenomenon has yet to be nailed down.

Some years ago, I read an article in a certain magazine outlining something known as 'Nested Differential Feedback Loops' and a design published for the constructor to make. Measured performance figures suggested this strategy, majoring on the lightly addressed area of amplifier feedback, would bring about substantial improvements in the reproduction stakes. I read this article many times over the years leading to my own thoughts on the subject of feedback.

To date, most designs employ a 'Monkey see, Monkey do' system where a proportion of the out put of the amp is channelled back wholesale as far as the frequency spectrum is concerned, to the most sensitive part of the circuit - the input stage. This feedback is not the pure version of the large signal the amplifier is sending out but a melange of unavoidable trash being returned by that giant motor - the loudspeaker voice coil along with associated crossover components. Stopping a voice coil and speaker cone is one thing but reversing its direction instantaneously is a whole different ball game - rather like putting a formula one race car into reverse on the straight and expecting it to instantly respond. Whilst the coil in quiescent mode is simply an inductance which becomes a linear motor, under drive conditions it becomes a generator and who knows just what it gets up to between these states.

The signal presented to the amplifier circuits via the cables - which incidentally may transfer or 'snub' various harmonic content as it may please them to do, is by no means an accurate facsimile of the outgoing force from the amplifier as we like to suppose and truly contains a whole panoply of self generated trash for the feedback to deal with.

At this point, I'd like to return to the original thought and explain why feedback is used: A proportion of the output from the powerful drive signal is returned to the input section to maintain stability and reduce the distortion to acceptable figures. This returned signal in no way represents what was sent out and the input stage of the amplifier, tasked to respond, finds all manner of trash it has to deal with or most likely, ignore completely. As there is no such animal as a 'clairvoyant' electronic circuit, the response is always behind the beat. Traditionally, the frequency spectrum is returned wholesale with little or no regard to 'tailoring' what is sent back or dumped and the front end, in attempting to deal with this unwanted intrusion, injects further trash into the equation.

You'll note that distortion figures are usually calculated using a dummy load or at best, a resistance shunted by a capacitor - never a combination of various components representing real loads in real time.

My thinking along the lines I've outlined above has led to designs that limit certain bands of energy from reaching the input stages of the amp. Allowing only particular frequencies and phase angles (more discussions later) - those necessary to maintain stability, into the feedback loop has resulted is some remarkable outcomes. For starters, the treble region has been released to flow in a marvellous way, the bass performance, unhindered by restrictive feedback, achieves a depth of detail otherwise hidden to the listener.

My thoughts and deliberations are only the beginning as I see immense benefits looming on the horizon. Thinking 'out of the box' has brought about the SE series of amplifiers which, if granted further years, I hope to develop and hopefully, realise the sound I've had in my head for many, many years.

Thanks for reading so far, I look forward to further thoughts as the investigations gather pace.

Further Reading:

Relocation Clearout Continues:A Rare Nottingham Aanalogue Unipivot Tonearm.One of Tom Fletcher's finest here in nice con...
10/05/2026

Relocation Clearout Continues:

A Rare Nottingham Aanalogue Unipivot Tonearm.

One of Tom Fletcher's finest here in nice condition. Hand made by Tom in Nottingham and incorporating much radical thinking including the innovative method of preventing the customary unipivot 'rock'.

The result is a solid performance particularly when carrying moving coil cartridges - in my case - a Koetsu Red Sig.

The keen eyed will spot that I've rewired the arm with multi conductor Litz wire for improved resolution. The internal wiring ends at the base and so I terminated the leads to a tag strip then led the signals off by a fixed lead. This meant the arm leads had little effect on any turntable suspension system.

Fitted with the later counterweight system which came with later arms from Tom.

Including carriage World Wide, this rare tonearm is offered at £550.

Thanks as always for looking in, see you all shortly.

28/04/2026

Would a Mr Tim Smith, who enquired after Naim SBL crossovers, kindly contact me with his details.

07484 782048 or email

Thanks.

Midweek Meanderings Part Neuf:The picture is of a product my company RMS Ltd used to make for Stands Unique before the o...
28/04/2026

Midweek Meanderings Part Neuf:

The picture is of a product my company RMS Ltd used to make for Stands Unique before the owner prematurely retired to pastures new.

We named it the Reference Wall Support - a rather pedestrian title for something so capable of extracting an extraordinary level of performance from any turntable placed upon it.

The product enjoyed much success but sadly production ended with the closure of S.U.

The principle of operation is rather mundane in that all vibrations, however formed, eventually end up as being in the horizontal plane. This model is designed to take them to where they have less impact on a vibration transducer - the vinyl replay system being one such device.

Since we at Avondale Audio have no marketing machine or dealerships, the prospects of this model making a reappearance are slim, however, does the small but select group have any thoughts how we might bring this to market plus - would it be worthwhile investing the levels of capital needed to bring this before the HiFi owning fraternity.?

Your thoughts would be greatly appreciated.

Picture is of the RWS and the Genesis Twin Motor turntable.

Thanks for the thoughts and kind messages.

Weekend Revelation:Albeit slowly, the conversion of the NAP500 takes shape. Working from the power supply upwards, once...
24/04/2026

Weekend Revelation:

Albeit slowly, the conversion of the NAP500 takes shape. Working from the power supply upwards, once this is complete, the installation of the SE400 boards with all the control and protection systems will take place. Comprising of dual mono high power sections with multiple banked capacitors - one section for each channel to provide the massive power reserve for the output transistors. Then comes the autonomous sections for the front end regulators supplying a stable flow of precious Watts feeding the sensitive stages of the SE modules.

On power-down, the relays shunt down any residual charge in the capacitor banks ensuring safe connection of the Burndy leads.

Given the size restraint in the power casework, we'll have a custom toroidal transformer providing the power of around 1KVA

Here is a screen shot of the final issue for manufacture of PCBs and I'll bring you up to date once the boards are built and installed.

The weather is set fair so here's wishing you all a great weekend.

09/04/2026

Weekend Whisperings.

For some of you visitors to this page, the prospect of upgrading your favourite piece of Naim kit by the newest catalogue offering is a daunting one. Many of you have moved upwards and graced the dealerships with your hard earned cash however, for many of you, the current price list ensures the glamour of the latest shiny box is well out of reach.

Let's take a closer look at what music lovers are being offered if I may make so bold: Power amplifiers from major manufacturers are usually generic models, revised circuits derived from past designs with the addition of a few refinements both in circuitry and casework form and finish. Marketing strategy places great emphasis on the improved power supply, circuits and associated luxuries such as a mains soft start facility as with the latest from Naim. Take as another for instance - the Naim power pre-amplifier circuit which, although it slavishly copies the format of the initial 12, 32, 42 etc., the addition of extra power supplies with dedicated input connectors is designed to debar the owner from beating the marketing model by adding such supplies to earlier models.

In other words, you're stuck with what you have unless your credit card is subjected to further injury.

After almost fifty years of experience of these kind of sales techniques, I'm pleased to say that we are past masters at rescuing owners from the penalties of the dealer treadmill and helping them 'beat the system'. Finding there was a thriving aftermarket for used Naim kit many years ago and setting about discovering just how these relatively simple circuits work, it became obvious that a few well chosen alterations could bring the sound quality up by an order of magnitude.

We take out what shouldn't be there then build in what the factory left out.

Since those early days, much has been discovered leading to the production of leading edge electronics produced with not only a substantial hike in sound but a reliability much envied by the mainstream industry. Our design specs, materials and construction methods are some of the best in the industry - you may be confident that your equipment will not only sound astonishing but will remain giving pleasure for many years without gradual degradation.

We're happy to receive comments and even critical reports about our engineering - then there's the matter of the sound. . . .

We are well known for bring another level of music to the enthusiast with much of what we produce fittable by owners with a minimum of fuss. Our backup programme is second to none where we're able to guide customers through the process of improving their equipment beyond expectations.

More radical upgrading will need our workshop facilities where we bring your equipment up to a guaranteed performance that is far beyond the latest box offerings and for a fraction of the outlay incurred during visit to your favourite dealer.

Currently. we're closed for a short while but on re-opening, there will be some extremely tasty products for you to try on our famous sale-or-return policy and at no risk to your pocket.

Thanks for joining us on our page and we look forward to seeing many of you once our move is complete.

Kindest regards,

Les and Gavin

For those enthusiasts who are keen to upgrade their HiCaps by fitting a TPR or ASR perhaps after having a few drinks or ...
03/04/2026

For those enthusiasts who are keen to upgrade their HiCaps by fitting a TPR or ASR perhaps after having a few drinks or trying to do the work in a rush - here's the definitive wiring form you must follow when re-soldering the cables to the new module.

The pin layout of the TPR and ASR follows this configuration exactly - one we hoped to be soldier-proof.

Making assumptions kills perfectly serviceable products.!

To tickle the listening tackle, we're just putting the finishing touches to two pairs of SE230 monos:
30/03/2026

To tickle the listening tackle, we're just putting the finishing touches to two pairs of SE230 monos:

28/03/2026

I will say this one more time until the loudspeaker manufacturers sit up and take notice:

Simply recycling the same old wooden boxes and sticking some drive units on the front face will not advance the art in more than microscopic increments.

By all means make a piece of furniture if you must but as far as musical transducers are concerned, you're missing the trick by a country mile. Even the most heavily braced cabinet has detail sucking mass and will sit upon any idea that the performance is a realistic representation of the real event by absorbing those small details that make the hairs on the neck stand up.

Allow me to explain: We're dealing here with infinitesimally tiny particles of energy intended to be revealed as musical detail. Simply routing those particles into something as crude as a lump of compressed sawdust means that detail is lost as far as the performance is concerned. Yes, I know that measurements have been used to prove the integrity of the reproduction but there's no formula on the planet to confirm you've captured all the performance.

As the cabinet of an speaker enclosure has only one function in life - that is to contain air at various pressures and frequencies, surely it isn't beyond the wit and imagination of man to design enclosures devoid of the limitations I've outlined.?

More seed thoughts later folks, chip in with thoughts if you'd care to.

Relocation Clearout Continues:This time folks, a classic NAP250 in Chrome Bumper StyleComprising NCC220 Qudos Amplifier ...
27/03/2026

Relocation Clearout Continues:

This time folks, a classic NAP250 in Chrome Bumper Style

Comprising NCC220 Qudos Amplifier Modules, HCR200 Regulator Modules, SPM2 Loudspeaker Protection Module, Kemet 20.000uF Main Capacitors with plated Busbar, Genuine Brand New Mains Switch, Original Holden & Fisher Toroidal Transformer, New Signal and Mains Connectors, New Anodised Alloy CB Faceplate.

Probably the best CB Naim 250 on the market today

Comes with a twelve month warranty.

First £1750 will secure this part of Naim history

Address

Unit 10C Topland Country Business Park
Mytholmroyd
HX75RW

Opening Hours

Monday 9am - 5pm
Tuesday 9am - 5pm
Wednesday 9am - 5pm
Thursday 9am - 5pm
Friday 9am - 4pm

Telephone

+44 (0) 1246 200096

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