Michael Fidler Spartan 20 Phono Stage Review

[KSTR]

Sorry, I want to understand the sound quality of your RIAA preamplifier. Therefore, I ask about the quality of the radio components that you used. Burgundy capacitors are not Chinese noname? What kind of dielectric do these capacitors have?

Those are most likely polypropylene film and not necessarily "no-name". Could be Panasonic ECW, for example.

Mr. Fidler is a serious engineer, rest assured. He won't allow to use substandard parts.

To assess sound quality I suggest you buy one.

 

[restorer-john]

To assess sound quality I suggest you buy one.

That's what I was going to say, but decided on the troll alert .gif because it was more fun.

 

[Michael Fidler]

Those are most likely polypropylene film and not necessarily "no-name". Could be Panasonic ECW, for example.

Mr. Fidler is a serious engineer, rest assured. He won't allow to use substandard parts.

To assess sound quality I suggest you buy one.

You're right there - 100V double-ended polypropylene film, so distortion free, very low inductance, and very temperature stable. Lots of incoming quality control on these for tolerance/leakage at 70% of rated voltage (twice what they're subjected to in the design).

Unfortunately you can't get these from the big component suppliers, so I source them direct from the factory.

 

[Michael Fidler]

@Michael Fidler Congratulations on another excellent preamp. I notice you have a Spartan 15 mk2 available now, what changes did you make?

Nicely summarised this morning by HiFi Pig: https://www.hifipig.com/classic-audio-spartan-15-mkii-phonostage/

New enclosure, extra LFC settings (same as the S20), improved protection circuitry for 'PSU rollers'

 

[restorer-john]

improved protection circuitry for 'PSU rollers

PSU rollers! No way.

What about case, knob, switch, and foot rollers? And I reckon you could offer a "custom" LED colour of your choice for an additional fee...

 

[Michael Fidler]

PSU rollers! No way.

What about case, knob, switch, and foot rollers? And I reckon you could offer a "custom" LED colour of your choice for an additional fee...

The LED can be changed out, but generally modification is discouraged. If it gets broken in the process I'll be the one having to deal with it!

TBH, I haven't tested it with the 'line-input energiser' yet...

 

[Scoobz1]

Would look great in clear perspex all round or at least the top bit !

 

[cgallery]

TBH, I haven't tested it with the 'line-input energiser' yet...

That is simultaneously hilarious and frightening.

 

[JSmith]

Would look great in clear perspex all round or at least the top bit !

RGB LED's as well?


JSmith

 

[Scoobz1]

was thinking of a look like this : https://www.ebay.co.uk/itm/35636557...QKVV2R0PJE4z0FYbRsGtLL7ivopVQgWRoCYMwQAvD_BwE

 

[Thomas_A]

So we have a 300R stopper resistor. Not much for impeding RFI, but also not too bad in terms of noise contribution... I wouldn't like to try this for a commercial product, but each to his own.

Of more concern, IMO, is the front end gain is fixed at 30.6dB; flat for the passive RIAA network that follows. This means that if the gain is set for 41dB (300R in parallel with 180R for the second amplifier stage), we are going to see premature clipping/overload occurring at 6.5kHz, at which point the overall gain will drop below the gain of the first stage, compromising overload margin.

At 10kHz, the overall gain of an RIAA preamp with a nominal 1kHz gain of 41dB will be 27.4db, so with 30.6dB of gain in the first stage, it's evident that we are going to be losing 5.2dB of headroom exactly where we want as much as possible due to clicks and pops...

Just a short ? Do you mean 5.2 or 3.2 dB lost headroom at 10 kHz?

 

[Michael Fidler]

Just a short ? Do you mean 5.2 or 3.2 dB lost headroom at 10 kHz?

Should be 3.2dB, but 0dB would be best!

 

[Thomas_A]

Should be 3.2dB, but 0dB would be best!

Ok thanks, was a bit confused. ( I have a plan to build the PP4 version of the Muffsy (have the PP3) just because I am bit bored and like building kits, and also try up the voltage to 16.5V).

 

[DSJR]

Sorry, I want to understand the sound quality of your RIAA preamplifier. Therefore, I ask about the quality of the radio components that you used. Burgundy capacitors are not Chinese noname? What kind of dielectric do these capacitors have?

'Sound quality?'

Let's just say that what comes out should be basically what goes in only louder and with the necessary RIAA equalisation. If the loading is compatible, I'd suggest no need to worry about a 'bottleneck' in performance here, as all the distortion and 'character' will come from the vinyl source itself

 

[French Meloman]

Glad to see a test on another device designed by Mr. FIDLER. Beyond the SINAD performance which is excellent in terms of SINAD, what is unique is the almost non-dependence on frequency in overload tests. I'm pretty sure that high-end products that are sold 10 or 50 times more expensive are usually not capable of this performance. Congratulations to Amir for this review and to Mr. Fidler for the excellence of his engineering.

 

[WDeranged]

Glad to see a test on another device designed by Mr. FIDLER. Beyond the SINAD performance which is excellent in terms of SINAD, what is unique is the almost non-dependence on frequency in overload tests. I'm pretty sure that high-end products that are sold 10 or 50 times more expensive are usually not capable of this performance. Congratulations to Amir for this review and to Mr. Fidler for the excellence of his engineering.

For a few years I was sceptical that headroom was important. Buying a Spartan 15 cured me of that pretty quickly.

 

[Muddywaters]

For a few years I was sceptical that headroom was important. Buying a Spartan 15 cured me of that pretty quickly.

Curious in what way you’ve determined this? I’m presuming (don’t like too but) you are comparing it in someway to other phono pre’s or singular pre in some way? Thanks

 

[WDeranged]

Curious in what way you’ve determined this? I’m presuming (don’t like too but) you are comparing it in someway to other phono pre’s or singular pre in some way? Thanks

Since I got back into vinyl surface noise bothered me to the point that I spent a small fortune on a Sugarcube. But some pops were so loud even that couldn't totally clean them up.

I'd heard that pops and clicks could be made worse by a preamp with low headroom. I didn't truly appreciate how much energy a little pop could have. I tried four other well known budget preamps (all shown on this site to have low clipping headroom) before getting the Spartan.

I pulled out a load of records from my reject stack. Most of them played back beautifully clean with the Spartan 15. The Sugarcube had no trouble with them now.

I was so very pleased to learn this.

 

[Muddywaters]

Since I got back into vinyl surface noise bothered me to the point that I spent a small fortune on a Sugarcube. But some pops were so loud even that couldn't totally clean them up.

I'd had heard that pops and clicks could be made worse by a preamp with low headroom. I didn't truly appreciate how much energy a little pop could have. I tried four other well known budget preamps (all shown on this site to have low clipping headroom) before getting the Spartan.

I pulled out a load of records from my reject stack. Most of them played back beautifully clean with the Spartan 15. The Sugarcube had no trouble with them now.

I was so very pleased to learn this.

Interesting, thanks.

I’m using the Puffin and Waxwing very successfully but my large lp collection has been culled and deleted of problematic lp’s. Most that had issues were gifted over many years. I’ve generally just replaced any that I want a good copy of others go away.