Nick Gorham's Audio Stuff...

Panoramic view of music room

Here is a attempt to put together a view of my music room. Its a small room 11 by 16 foot, with a hight of 7ft at one end dropping to 6ft at the end the speakers are. It does sound like its a bit too small, but it seems to work quite well. I have played around with audio analysis software (Acousti Soft's ETF software) and other than a bit of carpet on the roof between the chair and the speakers its not that bad. Though the padding between the speakers and the wall is there to dampen down a peak at about 80hz. With that its flat to within +- 8db between 40-18k, and as my hearing seems to only want to go to 16.5Khz these days that good enough for me. You may think the that is quite a way from a flat response, but you should try measuring your own room, you may be shocked, just how much those nice flat lines in the mags only happen in test chambers. For what its worth I normally listen at about 92Dba.

This is my vinyl source, which at the moment I am tending to use more than CD. Its a old (late 70's I think, I got it second hand in the early 80's) Linn LP12, with the Nirvana spring and bolt upgrade and a Valahala power supply. The arm is a Linn LVX+ (Basik), and the Cartrige is a Ortofon MC15 Super, feeding a Trichord Dino phono amp, using the standard Dino power supply.

I am working on a valve phono at the moment, watch this space

. And here are some later pictures.

The deck sits on a couple of marble slabs, with some steel rods between them to level the top one. The floor in the room slopes quite a bit.

I do have a nagging desire to replace the arm with a Origin Live modified RB250, but I am quite happy with the sound so far.

I have done some more analysis of the LP12 and this can be found here

Here is my digital source, a Musical Fidelity 3D CR, I had a chance to buy one, so I thought "What the hell". Not sure what else to say, I like it, its almost as good a vinyl :-).

This is now out of date, I have moved from the MF CD Player, to a modified DVD player. I will be putting a page together about this soon.

This is the amp, a World Audio Design KIT6550, built by myself from a kit. Its a Ultra Linear design using a ECF80 as input buffer, and phase splitter, and a pair of 6550's as a class A push pull output stage. It uses valve rectification in the power supply, thats handled by a pair of 5U4G's. I am very happy with it, and have spent many happy hours tweeking (see below) and would happly recomend it to anyone looking to move away from solid state amps. It delivers 40 watt per channel, and seems to have a flat response (within 0.5db) from 15hz to 30Khz at 1 watt output, and has a measured output impediance (if you are interested) of just less than a Ohm (0.9), not that good by solid state standards, but good enough for valve.

This is the inside of the KIT after I had finished building it. Its not as tidy as I could hope for, but it will do. To be complete, here is a list of tweeks I have done to it.

  • Changed cathode bypass caps to Black Gates.
  • Changed the output cathode resistor from 500 to 560 ohm, to be a bit nicer to the output valves. As it was it was a bit to close to the limit of anode dissapation for my liking.
  • Replaced the coupling caps with LCR PolyProp ones.
  • Replaced the volumn control with a Alps Blue.
  • Replaced the bridge rectifier and single cap, feeding the ECF80's heaters, with fast diodes and a Pi filter 4700uf + 1.8R + 4700uf.
  • Bypassed the PSU caps with 1uf and 0.01uf caps.

This to is now old news, I have been bitten by the single ended triode bug, I have started detailing my spiral into insanity, starting here

For interconnects I use Maplin shark cable, much better I think than the QED Silver Spiral I was using, the QED seemed to make it very "polite". I am going to try making some CVH silver interconnects some time soon, teflon tube is ordered.

The speakers are ProAc Studio 125, I listened to quite a few speakers in the price range and these suited me best. I did consider PMC FB1's but they just seemed to have a "shouty" quality that I didn't like. The 125's may not have the best bass extension (though more than enough, given the size of the room), but then have (IMHO) a lovely midrange, and seem to be a nice easy load for the amp to drive. And at 91db they are more than sensitive for 40 watt's.

For speaker cable, I have made my own out of CAT5 network cable. Not sure how that would compair with some of the silly money cable that is available, but to my ears, it was a lot more transparent than the QED cable that I used first.

This is the rest of the rack, a Denon TU 260L Tuner, a elderly A&R A60 amp, and a equally aged Technics RS-8555 tape deck. I use the A60 mainly as a reference for the valve amp, to make sure I am not loosing the plot after a change or tweek.


Just to be complete, here is a list of other things I am involved with Open souce implementation of Microsofts ODBC Lurcher Search, and rehoming

If anyone wants to drop me a mail about these pages, to offer strong drink, or professional support of the medical kind, I can be found here

And a course a link back to the page