Goldpoint SA4M-47 passive 'preamp' winging its way to Marco Towers...

[Marco]

Oh, and just to correct the uninitiated elsewhere, who've made stupid comments like this:

All he has done is load the input to the stepped attenuators, the stepped attenuators are still the same SMD crap that was there before.

Pay proper attention! The original series attenuators (the SMDs) now act as variable shunt resistors. The series attenuators in use now are the AudioNote Tantalums. That was the whole point of rewiring the switches, and why the performance of the unit, as a result (as it now uses only one very high-quality series resistor in the signal path), has been considerably upgraded

Marco.

[walpurgis]

I wonder if Goldpoint are looking at this thread? I'm sure they must have evaluated many resistor types during the design of the item.

[Marco]

I believe they did, hence why they made the comment about selecting the Nichrome SMD variety, because they considered them as the best sounding, but I doubt they'd have tried the ANs or Z-Foils, as they'd add too much to the cost of a commercial product.

That's where the benefits of judicious modifications come in: taking an already excellent product and elevating its performance to an even higher level, beyond the budget cost-effectiveness of a commercial manufacturer. Almost every piece of kit in my system has been subjected to such, with great success!

Marco.

[Marco]

Just as a further little experiment, because I wanted to try the excellent Shinkoh Tantalums (but didn't do so originally because they weren't available in 20K): http://www.hificollective.co.uk/comp...resistors.html

...I've ordered 2 x 18K 1W versions, just to see what they're like. Hopefully, being 18K, they won't be too 'loud' on the lower steps of the volume controls. If I like them better than the AN Tants, I'll use them, but if they're not quite as good, and I prefer the 18Ks, then I'll order the AN Tants in that value.

All interesting stuff!

Marco.

[awkwardbydesign]

I went through a similar process for the I/V conversion resistors in my Chameleon DAC. I used Shinkoh tants, as the ANs were magnetic at the time. Carbon= warmer and softer, metal film=sharper but harder, Shinkoh="bigger", Z-foils=disappeared. All relative of course. I used the Texas Components Z-foils; they make Vishay's Z-foils, but I don't know if they are all the same or not. I buy them direct.
One thing to bear in mind is lead length - the Z-foils had the longest leads which may (or not) make some difference. One reason for using SMD resistors, short path.
I may retry the Shinkohs at some point, as my sytem has changed since.
Now, for a proper test, you need to find a volume level you are happy with, and use single resistors of each type in the shunt leg!

[Marco]

More self-serving nonsense from 'elsewhere', spouted because that's what he wants his fanboys to believe:

No SMD (surface mount device) fitted attenuator can ever be as good as one fitted with proper good standard (through hole) resistor, it is not possible. SMD was created for production purposes not quality, for circuits that are not critical to component quality. In fact they are often seen off by a good pot in this application.

That might be your experience, but it most certainly isn't mine or that of countless others. Both DACT and Goldpoint have been using SMDs in the design of their stepped attenuators for years, and their products are amongst the most respected on the market, used in many professional applications. You don't get that sort of reputation if your products are crap!

Furthermore, the DACT and Goldpoint stepped attenuators have totally outperformed any pots I've heard within the applications I've tested them in. They're certainly the quietest and smoothest in operation, which is testament to how well made they are. The quality of the switches themselves is outstanding. That was one of the main reasons why I chose them.

That's not to say, however, that some pots might work well or better in a different application, such as in your own passive preamp. After all, it's all about achieving synergy, and not only YOUR version of that is best

The only reasons why the Goldpoint sounds better now than it did originally is because it has now been converted from a series to a variable shunt-type device, using superior quality series resistors than were originally fitted, thus improving SQ for that reason, and notably because there is now only one series resistor in the signal path, instead of (at some positions) 47! However, I still retain the flexibility of volume adjustment, with the 47 steps: a win-win in anyone's book.

The original Nichrome SMDs, now acting as shunts, have little influence on the sound of the unit (or certainly nowhere near as much), so get that into your thick head. I shall now return to enjoying the superb sounding music from my system and respond no further to your blinkered and ignorant pish

Marco.

[Marco]

I went through a similar process for the I/V conversion resistors in my Chameleon DAC. I used Shinkoh tants, as the ANs were magnetic at the time. Carbon= warmer and softer, metal film=sharper but harder, Shinkoh="bigger", Z-foils=disappeared. All relative of course. I used the Texas Components Z-foils; they make Vishay's Z-foils, but I don't know if they are all the same or not. I buy them direct.
One thing to bear in mind is lead length - the Z-foils had the longest leads which may (or not) make some difference. One reason for using SMD resistors, short path.
I may retry the Shinkohs at some point, as my sytem has changed since.
Now, for a proper test, you need to find a volume level you are happy with, and use single resistors of each type in the shunt leg!

All good and valid points, Richard. Don't worry, we're already considering that!

However, I'm not totally convinced that the shunts are as sonically influential. Is your experience contrary to that? Yup, in reality, the Goldpoint is still 'work in progress' - but considerable progress is being made

Marco.

[awkwardbydesign]

Wish I'd been there to hear all that. It may (and may still) have influenced my selection of resistors for a couple of projects.

It makes one realise why some makes appear costly for seemingly the simple designs they manufacture. Audio Note spring to mind. I'm sure they spend a lot of time and money actually listening to the effects of every discrete part of what they make.

http://www.audionote.co.uk/articles/...dio_hell.shtml Which I believe is a better way.

[awkwardbydesign]

All good and valid points, Richard. Don't worry, we're already considering that!

However, I'm not totally convinced the shunts are as sonically influential. Is your experience contrary to that?

Marco.

Not in this context, as I haven't experimented. But in speaker crossovers, yes.

[Marco]

Ok, noted. No doubt it's one that'll probably get the better of us... We'll try it in Duncan's own passive unit first, to see if it makes any difference, as it'll be easier to implement there, and if successful, modify the Goldpoint accordingly.

You certainly can't have all this fun (and useful learning) by boringly sticking with a stock product!!

Marco.