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You can buy the Neutrik Combi-jacks from Hung Brothers or from LHS. It's solid core.

Ay hello... The Rev 2 was built darn long time ago! hehehe.... The Avel wouldn't make much of a sonical difference. Just build-quality that I seek in it.

Inclusive of whatever R&D from the start. It took over a year. The RCA's were bought online. They're S$43.00/ pair. Vampire does have the equivalent 800C male RCA plugs. You can do a rough estimate: Holco's sell for US$0.60 a piece online. I bought 40 pieces for each value needed to match. The Noble pot is S$50 at Well Audio Labs. The Augat switch I used for power is US$12+ at Welborne Labs. Teflon insulated silver wire sells for at least US$2.40/ foot online and that is only 4N. Not the 5N stuff I used. The Vampire RCA's are S$43/ pair. So on and so forth. They're bias into Class A. But not as insanely heavily as the 2nd revision. Biasing opamps into Class A improves their sonic performance. However, as the bias current increases, the heat dissipated in the opamp increases too. As the opamps run hotter, their sonics become worse. So they would need heatsinking to allow high bias currents while not running too hot. In this case, I opted to use a lower bias current where it only runs lukewarm without need for heatsinks. This lowered current is still sufficient for my listening volumes.

Some information about the amp. As with the BBamp Rev. 2, this Revision also used PTFE insulated, ultra pure, 5N (99.999%) silver wire in the signal path. For power connection between the switch and amp, I used PTFE insulated, ultra pure, 6N (99.9999%) copper wire. The same stuff used in the top-of-the-line XLO cables! In the 2nd revision, I opted for low mass gold-plated RCA's. Less metal in the signal path is always better. Especially if the metal is brass! In this revision, I opted for very much more costly Vampire CM2F/ OFC RCA jacks. These are not low mass but they're made of oxygen-free-copper and gold plated! The volume pot is still the same high quality Noble pot used in high-end equipment from Cary Audio Design and Ray Samuels. I feel it's the best continuous rotation pot available now. The resistors used are NOS, non-magnetic Holco H8 resistors. These have copper leads and end-caps which are non-magnetic unlike ordinary metal film resistors with Nickel end caps. However, this means that great care is needed while bending the leads or the end-caps may break and the resistor becomes noisy. I personally handmatched the Holco's. =) The opamps are each coupled at the feet with Sanyo Oscon capacitors. These are extremely low impedance and high ripple current capacitors and have massive filtering capabilities. I'd say they're better than even the best Blackgates for power supply purposes. The output jack is a Neutrik combi-jack. The reason for this choice is the feel of using the jack. My original intention was to use the Neutrik locking jack with gold-plated contacts. However, the excessive force required for it's usage put me off. The opamps used presently are OPA627BP's. The best low gain stable opamps from Burr Brown. This is the same as the BBamp Rev 2. However, they're not biased into Class A as heavily as the Rev. 2. The bias current for each opamp is maintained at a level where the sonic benefits can be reaped while allowing the opamps not to run overly hot to required cooling. Edit: I'm currently testing out AD843 opamps in the circuit. Preliminary impressions are that the opamps are about on par. There is a slightly different tone to each of the 2 but the amp remains very dynamic, neutral, musical sounding nonetheless. The AD843's however, run very hot (60'C) even with a low bias of 4mA per opamp. Right now, I believe it's just a matter of personal preference as to which opamps stay in the amp and get heatsinked!

Heart of the amp. This design is is very similar to the BBamp Rev. 2 which av98m now owns. However, I'm using handmatched, NOS, pure copper Holco resistors and coupling the opamps directly with Sanyo Oscon's. Amongst the best of each of the 2 types of components! Close up of the workz:

The power supply: Toroid brand toroidal transformer. I intend to replace with either a Talema or Avel Lindbergh encapsulated trans. soon. Hybrid power supply with RC filtering for noise removal and filtered zener for regulation. Filter caps are low impedance Panasonic FC's. The zener filter caps are very low impedance Panasonic HFZ and the output caps are Panasonic FC with Sanyo Oscon's!

pr0n:

Finally completed my amp after a long time... And so.. I present to you guys: the BBamp Rev. 3. =)

I think the WBT NexGen solid silver, low mass RCA's (US$87/pr) would do better. LoL.. But the cost is a little inhibitive. Parts cost alone for 6 pairs of Vampire OFC RCA's, 2 Elma selector switches, 8 feet of Kimber AGSC, 2 nice brushed aluminium knobs and a Hammond case would be about ~S$650.00. A little on the high side and it ain't even inclusive of labour. LoL.. I think something like C&K switches together with the low mass RCA's I used on the BBamp Rev 2 and XLO teflon insulated 6N ultra high purity copper wire would do fine. That would be much lower in cost.. Probably about S$100 for parts alone. It's not that expensive.

Yea. That's the type of casing but I bought mine at SLT, 3rd storey. The shop's called Bell, I think. Mine is deeper and taller but less wide than the one in the picture. IIRC, the piece in your picture is about $20 at the same shop.

You'd be surprised. I bought a nice case from SLT for $29. It's like a small rackmount chassis about D32cm * W22cm * H10cm. Powder coated black and with a 2mm thick steel faceplate too boot. All 6 sides + faceplate are held together by screws. It definitely doesn't look like a cheap case in any way at all. I guess you just have to look around more closely to find the gems.

I've also modded my Pioneer PD-S904 player at about the same time. Pictures can be seen under my Yahoo Pictures Folder at: PD-S904 Mods Other mods including re-casing and seperate analog + coaxial output stages will be done at some other time.

There isn't any problem with the thump/ "piak" sound from the amp. Difference opamps behave differently when the voltage on the rails drop (ie. when the power from the transformer is cut). Burr Brown opamps tend to give the thump whereas Analog Devices opamps generally don't. Most headphones wouldn't be affected as they tend to have tolerance for relatively high power dissipation.

Get at least an Alps Blue pot, a pair of 0.47uF Solen capacitors and 10 pieces of 1%, 1/4w metal film resistors for each value you need. Parts list (amp only): 1 x 100k Alps Blue Velvet pot. 2 x 0.47uF Solen Fastcaps 10 x 100k ohm 10 x 5k ohms 10 x 1k ohms Input & output jacks

Yep, that's true. But I wonder about the scientific reasoning behind it as well. Does the distortion's audio range usually fall out of the speaker's handling range? Thus causing the damage? Lower powered amps w/o enough voltage swing would have it's output saturated most or all the time. The result is a flat voltage output into the speakers/ headphones. That's to say, DC input into the drivers. As driver coils are meant for AC/ varying frequency pulses, pumping DC into them would cause them to heat up more than they normally would. Hence, they burn up.

If you ain't half-deaf, they can drive the K1000's with more than enough volume.

He's quite a nice fella actually... I guess you keep catching him in a foul mood... LOL!

If your amp is up to the job, Grado's make good.

Other stuff: Removed the solder on the opamps and output RCA jacks. Replaced with WBT silver solder on the signal paths. Power pins of the opamps were soldered with Kester Eutectic solder. Improvements? Better seperation, details and less muddied sound.

Bypassed the opamps (special (PITA) 9-pin SIL opamps courtesy of JRC) with 0.1uF Multi-layered ceramic caps:

Both channels done. Can see the puny, short Oscon's towered over by the Panasonic HFZ caps:

Extra leaflets: Just bought a Pioneer PD-S904 CDP today. Sunk in an upgrade after just an hour of getting home. Replacing the Elna Silmic & Starget caps for the DAC's with Sanyo Oscon and Panasonic HFZ (Lower imp. than FC) caps respectively. One channel is already done.

The perfect murder:

The accomplice:

Clearing the mess: