The much anticipated event on the local audio calendar is finally here... NoiSing07, on 8th September 2007. Not having a NoiSing in year 2006 surely must have created a void as the displays in NoiSing07 is easily the best of the 3 we had so far. The venue was Republic Polytechnic. We had two rooms, one on level one, the other on level two. Accoustics was to die for. In my opinion, Level two had the better of both rooms. It is meant for panio practice. Fully treated even on the ceiling. This room was dedicated to Solid State gear. On level one, we had the tube gear, and easily the larger crowd of both rooms. This year, we only had one full range single driver speaker, represented by the famed Freastrex driver, courtesy of Willam Ang. We had quite a few preamps, two Audionote M7 designs, one other that I'm not too sure of, two Akido preamps, a Sakuma Tube buffer using 211, and my 5687 with Tamura output transformer. The main eye candy is the speakers... Ken helped setup the electronic crossover to enable a three way system using his Dukane plasma tweeters, Maxonic fieldcoil horns, 340hz Azura with TAD2001, Karlson bassbin with 18" JBL drivers, 15" Altec BR box... For the actual list of components, take a look at the echoloft posting. Both rooms had great sound. I was impressed by the ML preamp in the Solid State room, with a virtual control from the laptop. Eusof's (Synthesis) Vifa speakers, although bookshelves, turned out to be a beast to tame when we heard the solid state amp happily clipping away. It produced astouding sound when driven at moderate volume. Had to do a double take to be sure that the Orions are not playing. The 3 way setup at the tube room was equally astounding, given the 5 mins tuning of crossover by Ken. There was a distinct lack of amplifiers. I thought Ken joked with me when he mentioned that he was waiting for me to bring amps. All in all, a great way to spend a Saturday. Really enjoyed myself there. Unfortunately I was not able to stay all the way till 6 odd. Kudos to the organizer (Johari) and all those who helped in this event. Mervin (MB) did a fine job by helping us book the rooms at Republic Polytechnic. A big clap for all those die hard DIYers who brought their geat to RP! The morning rain was not enough to stop us! More pics here.

and it's about time... since the holidays are well over and work has taken on the 4th gear. :P an idea for a preamp that started off as a transformer volume controller, to a dht preamp, and finally to a noval indirectly heated preamp with output transformer. and it turned out that i built the 5687 preamp with LED biasing and tamura A4714 output transformer. all these is with parts that are on hand... mostly... even the chassis is made from aluminium that are lying around for some forgotten project... just so happens that the width of the aluminum plates are 10mm longer than the width of the A4714, making it a suitable candidate for a tower chassis... and so it is. for an easy chassis build, i got 2 MDF to be the front and back of the preamp. the pesky thing about 3/4" thick MDF is that it is a hassle to make a hole for any connector thru it... the 5687 was wired as double sections to lower the plate impedance so that it will better leverage the 5k output transformer. heaters are in series, fed by 50000uF of elna capacitors and 2 paralleled LM317 set up for 830mA current regulation each. this gave around 11vdc. a little low as i used a common 1R5 coffin resistor for the LM317. maybe i should series a 1R and a R47 to achieve higher output current... but well... i have not known anyone who used tubes till they die of cathode poisoning... plus i used raytheon 5687wb and not the super expensive bendix 6900... so what the heck... rca plugs for the input selectors are actually stripped from my neutrik rca from the m10 project. the output plugs were from canera rcas. volume pot is a 100k blue alps. signal wires are silver upocc wires, copper hook up are upocc copper wires, umbilical are multistrand 14ga upocc copper. all wires from ahfartaudio. in fact, my drd used all upocc wires internally. silver was used for signal path. power supply portion was built on a hammond chassis meant for another forgotten project, using some handsome irons from nick chua. it is rectified by the rca 83 mercury vapor full wave rectifier, two 50H chokes and many 220uF philips capacitors. future mods would be to add the constant current source that i implemently wrongly... which led to a loud bang upon power up, with bits of the transistor flying out. hahaha... ;) here's a flickr set of the preamp.