Hi, could you explain to me how being balanced relates to bi-amping? They seem unrelated. I thought balanced lines (XLR connectors) were used to reject hum and noise, especially over longer lengths of cables. Your choice of silver is also interesting. Mostly I read that it sounds brighter than copper. Now, I don't find my 325i excessivley bright but many folks here seem to think that, in general, the Grado house sound tends to emphasize high frequencies. I guess your comparisons have led you in the opposite direction. Would you clarify for me? TIA.
Somebody correct me if I'm wrong, but balanced amplification involves no common Ground. The left and right channels are independently amped. This prevents each channel from being tainted by interference from the other. The problem with using a common Ground is that neither channel has a completely neutral secondary wire. By using the same Ground, each channel is employing a medium that is already conducting current for the other channel. It's a workable solution but not the ideal one.
Silver doesn't sound brighter than copper. That's a myth. Silver conducts better. Whatever benefits derive from slightly better conductivity (about 7%) translate into an audible difference, even over five feet of wire. Is it twice as good? No. Is it 7% better. I don't know. What's 7%? What I do know is that it reduces the impedance of the line and allows my headphones to perform better, particularly when working from an unamped iPod. I get better bass and better clarity in the HF. How can it do both? Well, it's not because silver is "brighter." It's because a better connection allows the drivers to perform better, especially when being run off the feeble current of a portable device. Do I really need better wiring if I have God's gift to amplifiers? Probably not. But running off an iPod or other portable device, silver performs surprisingly well - at least for its diameter. Using 24 awg of 99.99% pure silver wire, I'm thrilled at the improvement. I like the sound better than with the "garden hose" big, copper, wire. I also like the fact that it's more svelt - thinner and lighter than copper lamp cable.
I'm not knocking copper. Given enough copper, you can get plenty of conductivity - especially over a short cable and employing a decent amp. But given a choice between a thick copper cable and a thin silver cable, I'm pretty happy with silver.
Say Bilavideo, how many holes did you punch into the back of your 325i's to get that more balance presentation you talked about?
I might be willing to try punching holes into my 325i's but since I've not seen more detailed pictures or text (may have missed them somewhere) about the process I'm terrified I may damage or punch through the back of the diaphrams. So I'm wondering, just how much distance is there (say in mm) between the black felt-like backing and the diaphram?
Like you I also have a drill press, and if it's a short distance wouldn't it be safer to use a drill press to make the holes? If set on slow speed and with the depth guide set so the drill bit ONLY bite's into the fabric/felt do you think this would be a good method for making the holes instead of punching? Don't know if you've still got an extra/dead sr60/80 or whatever lying around but if so would you be willing to be our/my guinea pig to let us know if this approach works?
Only issue I can think of offhand is the shavings lodging between the felt/fabric and the diaphrams but I'd think a low vacuum should suck them out...what do ya all think?
Oh, and what diameter size (again in mm) holes/punches should they be? Thanks, and thanks for the great thread.
Every time I do this stuff, I keep telling myself I'm going to limit myself to four holes, which is what Grado does. Every time, I find it impossible to stop at four. Instead, I vent all ten holes. It looks like I've stumbled onto an addiction. When and where shall we meet? If I don't drink the coffee can I still have a doughnut? Will I find Edward Norton and Helena Bonham Carter there?
When you ask about the distance between the felt of the driver back and the diaphragm itself, keep in mind that the diaphragm forms a kind of semicircle, arcing over the front of the driver. This means, among other things, that the diaphragm's distance varies, with the greatest distance toward the center and the least distance near the outer radius of the driver. On the other hand, the all ten holes are found at the same outer radius from the center. But within each hole, there's a side the leans toward the center and a side that leans toward the edge. In terms of venting the driver without unwittingly venting the diaphragm, it helps to have an instrument that won't penetrate too deeply. I've found a ball-point pen to be the easiest and most ideal.
I dont' think it would be any safer to use a drill press for this work. First, I don't think venting the felt is difficult enough to merit a drill of any kind. Second, I don't think a drill bit - even one on a low setting - is a good idea for penetrating the hole. There's nothing to stop the drill from pushing through to the diaphragm. A ball-point pen can only be pushed in to a certain degree. I find it safer and easier.
As for the shavings, I've gotten used to blowing through the holes while closing and/or covering my eyes. There's a certain amount of dust and micro-debris that settles upon the driver. Blowing through the hole helps dislodge this debris. Otherwise, you'll hear a buzz on certain tracks. On the other hand, if you blow, you need to close your eyes. Otherwise, you'll get some of this stuff in your eye.
I've actually thought of replacing the driver back with wood and/or of replacing the magnet and magnet plate with a ring magnet. At the moment, I'm not up to the task, but I hope to be in the not-too-distant future.
Wait so the only difference in the drivers between the SR60 and the RS1 would be more better quality copper wire used? The housing (and cabling) justifies the huge price increase between the two? That's surprising.
I'm reluctant to make that statement. I honestly don't think the difference between UHPLC copper and standard copper is that great, especially on a voicecoil or over a few feet of cable. That said, the differences between an out-of-the-box RS1 and an out-of-the-box SR60 are large enough to merit a price difference. There's nothing wrong with that. I just think the idea of an unbridgeable gulf between the SR60 and the RS1 is a lie. When you buy the RS1, you're paying to have the hard work done for you - wooden air chambers, driver damping, driver venting, better cabling, maybe a different grill cloth, et cetera.
There's no reason to knock the RS1. I'm in the lifting business, not the wrecking-ball business. The RS1 represents a gold standard, not a rip-off. Instead, my gospel is that the SR60 is a diamond in the rough, one that could be brought up to RS1 standards - with enough blood, sweat and tears.
