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Do not disturb: By the river: Fullerton:

Was out yesterday evening till this morning with a good friend and took some pictures. Cropped but without any other adjustments made. I hope the colour matches on your screens since I'm using an LCD.

On the contary, it's actually relatively compact compared to the Rev. 3.

The wide-angle adaptor for my camera cost S$490. I'd rather sell my camera and get a DSLR than to buy the adaptor. Another alternative is a Olympus Wcon at S$190 + S$40+ for a 66mm(F) to 55mm(F) adaptor. But that involves buying the adaptor online which I don't have the time for receiving the package.

How many of you guys still use these?

It should be a T2.1A.

The internal wiring is not shielded. It is not necessary when you're using a decently built toroid. The magnetic field is actually quite small. All the wires in the signal path are located further away from the toroid anyway.

Sub-$50 for a pair of interconnects is ridiculous. I'd say, put at least $100 for a commercial cable or DIY a cable like Jan Meier's using Bullet Plugs if you don't wish to use the Neutrik Pro-fi's.

Just swapped out the OPA627's for AD843N's. The AD843N's with their higher current consumption do run hot! Nearly 60'C without heatsinking. I'm surprised they've not fried... LOL.. OTOH, I can't hear much of a difference between the AD843N (you can see it in the 4th pic. from top) and the OPA627P's. I guess my interconnects are a bottleneck now.

Innards in grey:

Another look.. This time beside the PD-S904 (modded) and with a pair of Grados being auditioned. The synergy is, to say the least, at least as good as an RA-1 with Grados!

I'm pretty sure those are Holco precision resistors. ie. They're not the older, better NOS but just your normal resistors with magnetic end-caps.

I personally felt that the locking function of the Neutrik Jack is not fool-proof. It's possible to yank the plug out with sufficient force. The clamping force of the contacts is such that it provides sufficient to prevent the plug from getting yanked out. Therefore, I decided to forgo the locking mechanism altogether. It's reversible and doesn't cost anything at all.

The force used to release the locking component of Neutrik Locking Jacks is somewhat excessive and may cause the chassis of the (pre)amp to bend. However, the jacks do look wickedly good! I've decided to come up with a simple and reversible solution to this problem. The problem lies with the spring used for the locking mechanism; It requires too much force to compress. There are 2 ways to deal with this. Namely, removing the locking mechanism OR replacing it with a spring with less tension. The latter requires additional money (and more importantly, time) to be spent (you'd typically need to buy a cheap ball-pen/ lighter to get the spring). This guide explains the former process. First, a look at the jack: and from the side we're interested in: We start by disassembling the jack. Begin by removing the screw at the side: The plastic assembly along with the contacts can then be seperated from the outer shell: The spring is right underneath the push-tab. Remove both from the plastic assembly: You can now see the locking-clip and the sponge/ foam like piece: Both need to be removed. Which leaves only the contacts with the plastic housing: Putting the jack back together is the direct opposite process except that we leave the sponge and locking-clip out. Replace the spring and push-tab into the plastic assembly. Replace the plastic assembly in the metal shell. Replace the screw (and the plastic washer!). Use the jack. =) Completed project:

Another picture with my headphones on top of the amp.

That may be call the Spot welding. Do you suppose teflon melts at those temperatures?

Not too sure about that. But I do recall there is a method of welding using electrical sparks that doesn't require a secondary metal to be welded in. I know most construction uses extra steel rods to be melted in and the excess metal is then grinded down.

You don't solder the crimped portion. You solder the part of the wire near the crimped portion. Hence, most of the electrical signal is conducted through the crimped portion whereas the soldered portion only serves to make the joint mechanically strong. There is also another method that is far superior to crimping or soldering. However, it's not something a layman can do. Arc-welding the conductors together. This ensures the best mechanical and electrical contact without any other metals involve. However, you've got to be darn skillful to prevent the entire plug from melting. LOL.. I believe there's some method of cold-welding but it's probably a very expensive and proprietry process.

Anyway, the amp sounds great for those interested to know. The voltage drift (DC) on the output is about 0.01mV according to my multimeter. =) The opamps actually run quite warm. However, I'm considering popping in AD843 opamps to see which opamp I prefer before mounting heatsinks permanently on the opamps. =)

About 158 ohms impedance assuming it's a similar headphone circuit to the CD6000 series.

Not true. Silver has higher conductivity. Yes, that's true. Silver is actually a very neutral sounding material. However, many cheapskates go for cheaper 3N (99.9%) pure silver or silver plated copper which can tend to sound bright. Purer silver like 4N (99.99%) or 5N (99.999%) silver actually has better extension on both ends while not sounding bright. For the information of those reading the thread, Overmind sells 3N pure silver, not 4N at the prices listed. If you wish to buy 4N pure silver, you might want to go to www.homegrownaudio.com instead as the price could be lower from them considering that the wire is professionally coated with teflon. ie. Almost no air gaps.

Not true. Screwing/ crimping can be superior (although not sonically) to soldering if the person who terminates the cables does not solder well. Pressure from the crimping/ screwing can provide more contact area between the conductors. A good method for terminating is to crimp and solder. You'd wrap the wire around the contact (if possible) use a pair of pliers to press the conductors together for a good contact. Thereafter, you'd use solder to form a good mechanical contact. Hence, the conductors already have good electrical contact and the solder if just to hold them together. If you surf the Echoloft forums, you probably came across my post that Vampire stuff are available at SLT. That is true for their low-mid range of products. Most of these are manufactured for Vampire by factories that also supply these parts to other unknown brands. Therefore, it's not impossible to find identical products that are labelled under other brands for much lower prices.

This is basically similar to the Rev. 2. There are a few minimal differences so it's not significantly different from the Rev. 2 that av98m owns. For the amount of money and time (and 1 year IS a lot of time) that I spent on it, you'd think I'm crazy if it doesn't sound good. =)

Hehe... Was going to post pictures of my CDP mods actually.. But the harddisk housing the pictures just crashed. Well.. That knob cost $15. Heh... I'd rather get a craftsman make a nice and big knob out of Cocobola. hehe..