Quote Originally Posted by struth View Post
Guess it will depend on what else is in the system as to a possible winner unless its in your face better...interesting read it will make as obviously i wont be there
Oh, most certainly. Passive preamps are up there as one of the most system-dependent components there is, so much will depend on which one the test power amp 'likes' best, and vice versa. Most important of all is that the source used has a healthy (min) 2V output, in order to drive the various passives properly. That will make or break results further down the chain.

In that respect, it's probably advisable for the source used to be digital. The last thing you'd want is a 'weedy' cartridge and/or phono stage upsetting the apple cart.

Also crucial will be placing the partnering equipment in such a way that the shortest possible interconnects can be used with the passives being tested - and those interconnects must also be low-loss, low-capacitance types. However, returning to my situation, I'm satisfied that I've got the Goldpoint where I want it to be for now.

I now only have one 'audiophile-grade' resistor in series with the signal path (the Z-Foils), and with having maximised the available volume on the lower steps of the switches (by using the optimal value of resistor for my system for that job: 20K), and with how the Goldpoint attenuators work, with less shunt resistors used in the early steps, than further up, I've optimised things for use at my favourite listening levels, positions 3-10, on the available 47 steps.

There will be some experiments carried out in due course with the shunts, in terms of upgrading them if necessary. However, based on what I'm hearing now (the sound is so open, detailed, dynamic and goddamn musical), I'm confident that their sonic effect is not as significant as that of the series resistors, and also that the shunt resistors currently fitted to the Goldpoint attenuators (SMT Nichrome) are already very good.

Quite simply, if they were seriously crap and holding things back to a notable degree, Duncan and I would've been able to hear it. Judging now by the performance of the Goldpoint, there's just no way that's the case. However, that's not to say that they can't be improved, but they're definitely NOT acting as a significant bottleneck

Here's an interesting article to read on the subject, and also on Audio Signal Attenuators in general: http://www.blackdahlia.com/html/tip_67.html

In terms of this discussion, this bit is most relevant:

Quote Originally Posted by Audio Signal Attenuators
The advantage of a series attenuator is that you only have one switch contact in the path. The disadvantage is that all 24 resistors are in the signal path all the time. Normally one would observe that the disadvantage out weighs the advantage, but it’s not so simple, as this type has received a new lease of life with the likes of DACT (which is a highly regarded piece of kit), and the much better priced Goldpoint attenuator. DACT and Goldpoint both take advantage of surface mount technology (SMT) type resistors, which are very small in size, meaning the 24 resistors can be tightly packed in a manner that almost resembles a single resistor. What I mean to suggest is this. Imagine a single resistive tract cut into 24 small pieces, and then soldered together, with switch contact between. If you can implement this neatly – tightly spaced and clean – then you start to feel a whole lot better about the series attenuator approach. DACT and Goldpoint do exactly this, thanks to SMT.
The emboldened text reflects my own experience of using controls with SMT-type resistors, as the DACT series-type attenuator I use in the Croft outperformed any shunted 'boutique resistor'-based attenuators I'd used in the past, which certainly confirms the theory that not all SMT-type resistors are bad. Again, as with many things in audio, it's all about context and implementation!

Therefore, given the above, it's no surprise then that the Nichrome resistors, employed by Goldpoint on their attenuators, aren't letting the side down. Indeed, quite the opposite, as they appear to be pretty much sonically transparent, which is why I'm in no hurry to replace them.

In terms of this bit from the above article, I quote:

"The advantage of a series attenuator is that you only have one switch contact in the path. The disadvantage is that all 24 resistors are in the signal path all the time", whilst unquestionably a truism, what Duncan has done, by rewiring the switches on the Goldpoint (as he outlined earlier), is provided me with a 'shunt-type' device, where as mentioned before, only one series resistor is line-line with the signal path, at any point on the switches, and depending on that position, will result in how many shunt resistors are being used: at position 1, one, and at position 47, forty seven, which is why it pays for me to achieve maximum available volume on the early steps!

Now, with having maxed out the low-level volume available on the early steps of the dials, by fitting the optimal value of series resistor (for my system), I will rarely, if ever, need to use the controls beyond position 12, which means that a maximum of 12 shunt resistors would be in use at any one time. However, in reality only 3, to a maximum of 10 resistors will be used, as positions 3-10 on the dials is where 95% of my listening will be done.

Therefore, if we consider that because the shunt resistors currently being employed in the Goldpoint are high-quality Nichrome SMT-types (as favoured after extensive research by Goldpoint), and that the principle behind using SMTs is, as the article above says, so that: "resistors can be tightly packed in a manner that almost resembles a single resistor", then effectively with using a maximum of 10, tiny, tightly-packed SMT-type shunt resistors, at the loudest positions on the dials I'm liable to use, then it seems feasible that, as claimed, those are indeed behaving similar to a single resistor.

That, coupled with the way Duncan has rewired the Goldpoint switches, so that only one series resistor is in line with the signal path, is probably why the sound I'm getting now is so good!!

It's also why I'm now in no hurry to change anything else, and simply allow all the new resistors to burn-in. Later on, I will experiment with replacing the Nichrome shunts, with Z-foils, which would probably be the ultimate, but for now, the stunning sound I'm getting is, shall we say, 'more than adequate'!

Marco.