In my previous story on using equalisers in high-end audio, I played with the Mackie QUAD EQ. It was a great box for the money and did what was asked of it very very well. But for me, I did not want to have to reconvert the audio from my high end DAC back into a digital signal, alter the sound, and reconvert the sound back to an analog signal. It seemed to defeat the purpose of the expensive DAC I am using.

The advantage of course was that tweaking the audio in the digital domain removed one of analog equalisers greatest problems, phase errors. So I was in a pickle, until I saw the high end equalisers used in Don Bartley's mastering suite. Even though we sell the Manley EQ's, it had not occurred to me to use them as I was stuck on having a digital EQ.

Mastering suite's where ALL of our CD's are 'finalised' use analog equalisers ONLY. The ones they use are the Manley Massive Passive and the Avalon Design range of equalisers, mainly the AD2077 which is a stunning piece of kit.

At over $16,000 it is not really viable for many users, and being a parametric equaliser, few audiophiles would understand how to use one correctly without a bit of research, but parametric EQ is in my view the best option. This is where the Manley Massive Passive at around $5,000 looks like an absolute bargain.

Another model from Avalon Design, the VT-747SP while primarily a Compressor Limiter, incorporates a six band graphic equaliser. This may seem somewhat limiting when compared to the 30 odd bands that the Mackie used, but in the 'real world' of tweaking your EQ, it is more than enough to achieve the desired result.

What I noticed in tweaking the Mackie was that I needed to remove mostly mid band sound around the 500Hz through to 6kHz range for my collection of 80's music, and give it a boost in the bottom end from 45Hz down.

Here is a list if the bands in the equaliser section of the Avalon:

• Variable amplitude LF +/-24dB 15Hz shelf response
• Variable amplitude MF1 +/-8dB 125Hz selected Q response
• Variable amplitude MF2 +/-4dB 500Hz selected Q response
• Variable amplitude MF3 +/-4dB 2kHz selected Q response
• Variable amplitude MF4 +/-10dB 5kHz shelf response
• Variable amplitude HF +/-20dB 32kHz shelf response

This may seem like an odd selection of bands and even stranger cut/boost levels on each, but trust me when I tell you this thing is all you will ever need to tweak your system and sounds extremely musical. The 2kHz and 5kHz bands take care of that nasty brightness in 80' CD's very nicely.

The top and bottom most frequencies may seem useless, but they have a very wide effect on the frequencies above 15Hz and below 32kHz and are the ultimate sweeteners for your system.

When I tested this unit today, I was more concerned with flattening the response of a pair of Usher RW-729 speakers which we unpacked this week. I have a review in progress in this section also, and noticed that they have a prominent mid band peak which I hoped would smooth out as they get burnt in. However it is a rather substantial peak, particularly when compared side by side with a pair of ATC's, so I thought I would see if I could get a similar response from the Usher's by tweaking the Avalon.

To my amazement I could! I am not so sure which I was amazed the most with, the performance of the Avalon or the sound of the Usher's. I will elaborate more on the Usher's in their review, so for now let's talk about the mighty Avalon.

The performance of the equaliser is extremely quiet, simple to adjust (unlike a parametric EQ) and incredibly musical. I then turned on the Tube circuit which is selectable via a front panel switch, and nirvana was found. There is something added by the tube circuitry other than the usual 'warmth' comment. Don't get me wrong, I loved the standard Class A transistor circuitry, but there is a little extra 'magic' when using the tube circuitry.

So all in all the Avalon is a superb bit of kit for your system, with superb performance, great build quality and looks to die for. But I hear you asking about the compressor circuit, isn't it a waste to buy this thing when it's primary goal in life is to compress audio?

The answer depends on your circumstances, and for me the answer is a resounding yes. I have three little children at home and at night when i am watching movies, I am constantly riding the volume control between quiet dialog and loud explosions etc. The compressor circuit allows me to run it as a full limiter, and 'cap' the audio peaks. This essentially makes the soundtrack of your movie all the same level, perfect!

Also, if like me you have your entire CD collection ripped to a server, and play back your entire 20,000 songs randomly, you would have noticed the varying levels of each song during playback and once again you are turning it up or down constantly. Once again the limiter can be employed to 'level out' your music for constant playback level.

Now, I am not talking about using the compressor for ANY other purpose other than background music playback during dinner parties or lazy Sunday afternoons with the stereo playing all day. Compressor's REMOVE the dynamics from the music and that is NOT what you want when you are enjoying your systems performance, but for the situations described above, it is a perfect solution, and being a very high end compressor, it is totally transparent in performance.

So I have found my audio nirvana, the Avalon Design VT-747SP is going home to be part of my ever changing sound system, happy days!

Tags: Equaliser

Remember in the late seventies when you simply had to have a graphic equaliser in your stereo or it simply was not a good system? They were cheap additions into most amplifiers and added far more problems than they solved.

The problems were two fold: one they added phase shifting errors to the sound, noise and distortion in most cases, but the greatest problem was with how they were adjusted. Almost everyone would boost the bass and treble end, creating the classic 'canyon' curve, thus removing all midrange detail.

Well we have all matured since then and learned an awful lot more about quality audio and have far better trained ears. So we 'should' be ready to use an equaliser properly this time around. But hang on a minute I hear you say, "I thought equalisation was a big no no in high end audio?"

Well it still is in many people's eyes, but I am at the point in my own system with speakers that are so accurate and revealing, that I am sick of most of my CD collection not sounding that good. Sure the Steely Dan and Lee Ritenour CD's sound fabulous, but put on just about any CD from the 80's and you get bright, almost harsh sound that is lacking in any serious bass content.

Add a good quality equaliser into your system and you can at the very least, EQ out the harshness and boost the bass end to provide an overall smoother sound. But, it has to be a good quality equaliser otherwise we will end up with the dreaded phasing issues again, so forget about running down to your local Retravision to pickup a $200 equaliser. Quality audio requires quality products EVERY step in the chain, but you knew that already...

So what have I put into my system you ask? Surely I have grabbed one of those Manley Massive Passive Mastering Equalisers right? No I can not afford it, plus it is an analog equaliser which is perfect for mastering, but it has no presets and I want to be able to save the EQ settings.

So I have ordered myself a Mackie Quad EQ (around $2000) which is a pro product, but it offers four channels of EQ, balanced audio in and out, 30 bands of equalisation with no-compromise 24-bit/48kHz processing and 99 presets. The fact that it is digital equalisation it should not suffer from phasing shifting issues at all, hopefully.



It arrives next week, so I will set it up and start testing it out, stay tuned for updates on just how well this works out.

UPDATE: The Mackie arrived today, it is a well made box and I have to say the specs of this thing are impressive. After connecting it to the test system it sounds rather transparent which is good. Took a little while to learn how to work it but it is very simple to use, in true Mackie style.

Thankfully it has a bypass button on the front panel which makes it easy to AB the settings against flat or no EQ. So it was straight to an 80's CD and I started to tweak the EQ curve. This was where the RTA (Real Time Analyser) really helped. You can visually 'see' where those pesky mid range peaks are and the truly lacking bass regions. So a simple cut and boost here and there and the CD suddenly sounds more listenable on a high end system.

I intend to experiment further with this box, try to get a bunch of presets that work for 70's and 80's music etc, and with up to 99 programmable storage places, it will be easy to recall when required. As it has 4 channels of EQ, I also intend to play with the built in noise generator and the supplied microphone to analyse the room and see if I can get this box to 'tune' the speakers to the room. More soon!

UPDATE 2: Well this morning I have spent my time putting the EQ between my pre and power amplifiers. I then setup the supplied microphone to analyse the room acoustics effect on the sound. What I found was some peaking in the mid range area between 80Hz and 1.6kHz, it was a rather bumpy EQ setting that pulled it back in line but it did it.

I then put on Dannielle Gaha's "You don't know me" CD which is a beautifully recorded album of standards. I used the  'Honeysuckle Rose' and 'Blue Skies' tracks for reference. Being a very well recorded album I did not need to use any EQ for it other than the room adjustment EQ between the pre and power amp.

The resulting sound was still very open and very very clean, the EQ is doing nothing other than what it is asked to do which in this case is to smooth out the peaks in the room. Fabulous!

My next test disc was a very well recorded CD produced by Charles Fischer from 1989, Gyan's self titled debut album. Although well recorded it does have some peaks in the upper midrange area which when listened to loudly is a bit grating. Simple adjustment of the EQ curve and all was fixed!

I have found the solution to my audio problems, at last. If I want to listen to my 'gear', then I can turn it off and put Lee Ritenour's 'Wes Bound' CD on and enjoy, but if I want to listen to some classic old music from my youth, then I turn on the Mackie, put Pat Benatar's classic 'In the Heat of the night' CD on and bliss out!

Equalisation does belong in high-end audio!

Tags: Equaliser