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

[brian2957]

Nice write up mate . The LDR is a bit of a dark horse it seems . Be nice to see where you go from here , particularly with the cables from my POV

[Marco]

Cheers, guys. At the end of the day, you've just got to tell it as you hear it - no point in kidding yourself on!

Based on what I'm hearing with the LDR, and what I've experienced from the passives I've heard to date: NVA P90SA (belonging to Macca), Tisbury, the Goldpoint and Duncan's DIY one, it's difficult to imagine any of the breed (regardless of the manufacturer, with much more components in their designs to impede the flow of the music signal), producing what the LDR does with music - or rather what it doesn't do...

Brian, the Beldens sound superb, mate! I'm just doing a bit more listening and comparing before I'll do a write-up on the cables

Marco.

[Hudz]

I reckon Chris(LDR) is gonna be very busy after that, form an ordererly queue folks but I already ordered mine ( cheers again R100 for the heads up)

Lovely write up Marco, mine now can't get here fast enough.

[struth]

Cheers, guys. At the end of the day, you've just got to tell it as you hear it - no point in kidding yourself on!

Based on what I'm hearing with the LDR, and what I've experienced from the passives I've heard to date: NVA P90SA (belonging to Macca), Tisbury, the Goldpoint and Duncan's DIY one, it's difficult to imagine any of the breed (regardless of the manufacturer, with much more components in their designs to impede the flow of the music signal), producing what the LDR does with music - or rather what it doesn't do...

Brian, the Beldens sound superb, mate! I'm just doing a bit more listening and comparing before I'll do a write-up on the cables

Marco.

Well Sov for one was very impressed with then to a degree that he makes them up himself now so they were always gonna be good. I dunno what the retail price of these things are( IE, a finished one), and it wont matter to me anyways but will be interesting to know how the spv or whatever adds up. Although not currently using it, I did like my tx based passive and am not surprised that an unconventional pre has done so well.

[montesquieu]

Seem to recall the DIY Hifi supply' EVA LDR passive and that Aussie bloke's one (Lightspeed?) causing a bit of a stir a few years back.

I bought an EVA II and liked it - worked well with some setups, but was a shade unforgiving in other circumstances - actually I found the experience similar to other passive experiments, in particular a high-spec Audio Note kit resistor jobbie, and a Music First Audio MkII TVC with the bigger transformer cores. (Pick of the bunch was the TVC but still not ideal with all sources).

Looks like you have a setup that likes passives, Marco but I think you are doing the right thing taking the Croft out for a while and letting your ears settle into it.

I had a similar epiphany when I first put the MFA in ... even though there was a slight loss in oomph with the phono stage, I was marvelling at the floods of detail and texture that were coming out.

But a couple of months later, putting in an active pre again (in this case a Shindo ...) turned things on its head. Be interesting to read your findings down the line.

[Marco]

Well Sov for one was very impressed with then to a degree that he makes them up himself now so they were always gonna be good. I dunno what the retail price of these things are( IE, a finished one), and it wont matter to me anyways but will be interesting to know how the spv or whatever adds up. Although not currently using it, I did like my tx based passive and am not surprised that an unconventional pre has done so well.

The secret is in its simplicity, Grant, with so few components muddying the music. With LDRs, there are just two optical resistors (for each channel) in the signal path, so their simplicity in avoiding switch contacts is where they excel.

As Chris put it to me in a PM, in reference to my experiment with resistors in the Goldpoint:

Keep up the good work with investigating resistors. Richard is on the right path with his comments on the Goldpoint, as you need to view the device not only by the resistor, but by the circuit board tracks, connecting wire, and above all, the switches, that look nice but sadly audio gets very lost in them similar to Lara croft and Tomb raider...

Indeed, and you can clearly hear when the detrimental effect of the above simply isn't there! The 'musical window', as it were, is effectively almost transparent

Marco.

[struth]

The secret is in its simplicity, Grant, with so few components muddying the music. With LDRs, there are just two optical resistors (for each channel) in the signal path, so their simplicity in avoiding switch contacts is where they excel.

As Chris put it to me in a PM, in reference to my experiment with resistors in the Goldpoint:



Indeed, and you can clearly hear when the detrimental effect of the above simply isn't there! The 'musical window', as it were, is effectively almost transparent

Marco.

Yes I get that Marco. The TVC doesn't have a lot inside either, although probably more than an LDR. It and my other amps get on well, and an LDR may well do so to. I will be switching between my systems from time to time as the both do things I like, but are different at same time. Currently enjoying the big Sony(a better amp than maybe it gets credit for tbh) and just sitting on my ample ass, as recommended to me by the boss of things.

[Marco]

Hi Tom,

Seem to recall the DIY Hifi supply' EVA LDR passive and that Aussie bloke's one (Lightspeed?) causing a bit of a stir a few years back.

I bought an EVA II and liked it - worked well with some setups, but was a shade unforgiving in other circumstances - actually I found the experience similar to other passive experiments, in particular a high-spec Audio Note kit resistor jobbie, and a Music First Audio MkII TVC with the bigger transformer cores. (Pick of the bunch was the TVC but still not ideal with all sources).

Yeah, I remember the Lightspeed. I didn't pay much attention to it at the time, although a friend of Ian's (Dave Hewitt) built one for him. I think Ian liked it, but didn't consider it especially remarkable. The 'Stereo Coffee' Chris designs is a different beast, using a unique circuit, tuned to his exacting requirements - and you can hear the difference. It really is quite special

Looks like you have a setup that likes passives, Marco but I think you are doing the right thing taking the Croft out for a while and letting your ears settle into it.

Passives work well here because (given a healthy 2V minimum digital input source, which is provided by the RPi or Sony DAC) the Copper amp is hugely sensitive, as are the Tannoys, so there's nothing that makes life 'difficult' for a passive, thus the system allows their talents to shine. However, I understand where you're coming with the active thing, as I've been there before, although I suspect things are a little different this time.

I've taken the Croft out of the equation for a while in purpose, as that way your ears become attuned to the 'passive thing', and how it treats music signals, so that when introduced again to the 'active thing', the differences become immediately apparent. It's the only way of doing things properly and ensuring that you end up making the *right* decision, as snap judgements tell you nothing worthwhile.

Anyway, stay tuned and see how it all pans out... It's been a hugely enlightening and pleasurable learning curve for me!

Marco.

[The Black Adder]

Hi Marco.

Very interesting indeed. I've always been interested in the LDR. I'm still quite sketchy on how it actually works though, I could do with some layman terminology if anyone can spare a few minutes?

I'd be very interested in hearing both Goldpoint and LDR together with my copper too!

Right now, though I'm loving the re-updated Croft, it's a real beast as it's perfectly matched to the copper and the sound is so fluid and snappy.

[Firebottle]

Hi Josie, I'll give it a shot at a laymans explanation.

A basic attenuator is a series resistance and a shunt resistance. A standard potentiometer in effect combines both with the wiper terminal dictating the resistance split between series and shunt.
As the series resistance decreases the shunt resistance increases, this ups the volume.

An LDR is a Light Dependant Resistor. The resistance varies due to the amount of light energy inside the LDR. Cleverly the light element, normally a LED, is completely isolated electrically from the resistance part. This means that when the resistance is in an audio circuit there is absolutely no degradation of the signal passing through the resistance.

To form an LDR passive two are used and arranged so that as one reduces in value the other increases in value, with a common control voltage.
This is the same as a series/shunt attenuator, hence a passive control.

Hope this is clear,