Hard wired heresy

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Hard wired heresy

Some years ago, whilst going through an obsessive period with hi-fi, I got onto the Naim track. Once I tuned into the grip and rhythm of Naim gear nothing else came close. Starting with a Nait integrated amp, I eagerly upgraded through the range as soon as funds would allow. Relishing every incremental improvement to the sound, realising what all the hi-fi fuss was about, unearthing all the wonderful information in my favorite recordings. I was on the road to nirvana and given enough time and money I would get there. For a couple of years I was happy.
But a nag was emerging; an aspect of the sound was beginning to bother me. Even after several upgrades in amps, power supplies, front ends and speakers, there was a problem with the sound. More worrying, was the fact that it became more apparent the better the equipment got. It reached a crisis when I shelled out thousands of pounds to buy the Naim flagship CD player of the time (CDS). It was a great CD player, way better than anything I had heard, but the problem persisted.

Trouble was afoot. Despite having a pretty good hi-fi system, and suffering sleepless nights fretting about all the money I’d spent, I had not been able to get it sounding right. The Naim dealer had run out of ideas to fix it and people were saying that I was hearing the limitations of what hi-fi could do. WTF? So I started reading the magazines, getting increasingly desperate to find somebody who knew or even recognized the problem. I tried a few tweaks, a dedicated 60 amp mains spur direct from the consumer unit, an earth stake, by-passed fuses; I even tried polishing the pins on the plugs. They made improvements but none made any difference to the problem that was bothering me.
I would describe the issue as a grainy veil over the music, it was particularly noticeable on female vocals, but actually it was across the whole spectrum. Then I came across a review of some Naim equipment and wondered if the reviewer was referring to my problem when he observed ’false detail, typical of the Naim sound’. Perhaps I’d jumped in too deep with Naim stuff, perhaps I had to ditch the lot and move over to smoother sounding kit? But whenever I heard smooth sounding systems it seemed like all the edges and little details in the music had been polished off. As if someone had been a bit heavy handed with the Brasso.

 

A Naim NAP 250 not unlike the ones that saw the hot end of Ivo's iron.

 

After a few months I had collected together a few magazine articles that offered promise. One was a column by Ben Duncan, he suggested that wherever two different metals are in contact with each other the interface might act as a diode. In an AC system this would have a rectifying effect. If this was in the signal path of a hi-fi system the effect would be deleterious. Another article was a DIY speaker project, at the end of the last installment some tweaks were offered noting that eliminating push-on driver connectors made an audible improvement.
An idea was taking shape. The easiest way to start was to get rid of the push on connectors to the drive units of my Epos ES14 speakers and eliminate the bolt-on connections to the ‘speaker terminals. Basic stuff, and easy to reverse. The results were encouraging. So much so that I started to think about other connectors in the system.
I carefully took my CD player apart. By removing the output socket on the back it looked easy to solder an interconnect directly onto the circuit board and feed it out through the hole. I didn’t want to destroy my Naim leads so I bought a couple of meters of silver interconnect from Audio Synthesis (who were very helpful and encouraging in my quest). It was time to gird my loins and go for it, soldering iron in (a slightly shaky) hand I tacked the lead in place. I couldn’t do it as neatly as the guys in Salisbury, but it was good enough. This was exciting, if it made the same improvement as hard wiring the speakers I was in for a treat. And…  it worked. Just the same as the speakers, it tackled the grain problem head on. And what became apparent was that the grain was corrupted information, so there was a double benefit; the grain was getting less and more information was getting through.

Now I was on a roll the amps needed doing too. For these I had to drill holes through the casework, not a nice thing to do. If I’d thought a little harder I could probably have got around this. Anyway, that’s what I did. Now I had soldered interconnects from circuit board to circuit board through the whole system except for the speakers where I soldered the cables directly onto the connecter tags of the drive units (ES14s have almost no crossover circuit, just a capacitor in the tweeter feed). I had eliminated over a hundred metal to metal contacts (you’d be amazed at how they add up). As my conviction gained momentum I got bolder, towards the end I was so excited I forgot about all the negative consequences of what I was doing (see below).
The result? Gob smacking. Truly. Goose bumps aplenty. I was staggered by the transformation. It was a massive improvement. Deeper, tighter, more articulate bass. The lumpiness I had put down to the limitations of a reflex enclosure had all but disappeared. A lovely clear top end was way beyond what I thought metal dome tweeters were capable of and the midrange was a revelation. Female vocals had a spine tingling smoothness and realism that I have never heard before. All that grain in the voice that I suspect was labeled ‘false detail’ was translated into real, believable detail. The background noise quietened down too. This was more difficult and subtle to assess, but the music seemed to emerge from a dark inky silence, giving a much more intimate, almost eerie experience. One mustn’t forget that throughout this exercise, the Naim traits of pace and open delivery were fully present and correct. When combined with the natural and realistic transformation the hard wiring achieves the system reached a different league of music reproduction. The overall effect was fast, cohesive, and organic. Easily beating a (Naim) system of two or three times the price in many respects. The mixture of relief from my grain problem and ecstasy from the increased resolution blew my socks off.
There you have it, very simple and extremely rewarding. But in conclusion I must balance the picture a bit. Hard wiring your system is quite a serious undertaking. It will invalidate any manufacturer’s warranty and it will effect the resale value of your stuff it you don’t make it 100% reversible. And yes, it’s a bit stressful attacking expensive kit with a drill and a soldering iron. Added to that it’s a pain in the arse, because it’s really annoying having all the components in your system soldered together. But to my ears, there is no choice if you’re looking for a glimpse into true fidelity.

Ivo Rousham

Ivo’s system consists of a Naim CDS CD player, home made passive 'preamp' (actually it's just a high quality input selector switch with the sliding contact bypassed and a few Vishay resistors), two NAP250 power amps bi-amped and heavily modified Epos ES14 speakers.

 

Comments

Excellent article Ivo, I do understand your path of reasoning and result and i am glad that not only did you suceed but shared your results.I used to sell Nap 250 along with LP12 and Isobariks et al,  back in 1978. I was lucky as many new hifi designers came to the shop to demonstrate their new equipment and i heard new equipment and talked to the designers about their ideas, including Ivor and Julian.I had a great deal of respect for Roy of Rega, he delivered a lot for a little.When i left hifi retail my options of choosing and buying hifi declined with the arrival of 2 daughters. I have often pondered the multiple "veils" in front of the music, observing that some some cheap/basic systems could deliver more "feeling and presence" than more eloborate and expensive equipment.My very recent kitchen equipment upgrade this summer was a little Denon RCD-M40DAB which boasts a shortened signal path. This is sourced from either a USB 128GB stubby filled with FLAC files or a Roku Soundbridge M1001 via optical. My point is both these "systems" have a minimal "metalic path" for the signal and the detail i can hear from the inexspensive wharfedale Diamond 220 speakers is considerable. when i play the FLAC files the only metalic path i can consider altering is the speaker cable/speaker xover. I used triple CAT5 cable and have yet to open up the speakers (only 4 weeks old)Meanwhile my OLD naim nac 12 nap 120 are both heavily modified in every way and non-operationl requiring a very total overhaul and one dead output stage on the 120. I used to run the 12 from 2 car batteries and the 120 off a torroidal PSU with big caps, with direct cabling used throughout. Almost every step of these 1980 era changes brought a small but significant improvement, some were the direct cabling others just PSU improvemnts.I have also tried a Tacima mains filter and appreciated the "silent black space" behind the sounds but on balance the reduction of dynamics was a greater loss. Has anyone else "direct cabled " their equipment?              Paul Yates

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