Gold Note PH-1000 phono preamplifier Measurements

Sidebar 3: Measurements

As increasingly appears to be the case with high-end phono preamplifiers, the Gold Note PH-1000 is a complicated product. It has single-ended and balanced inputs, and one of the latter is capable of accepting a line-level signal. It has balanced, single-ended, and headphone outputs, with the option of either taking the output from the phono stage (Stage) or a preamplifier stage with a volume control (Preamp). (The latter appears to be the default for the headphone output.) Each phono input can be set to MC or MM, with gain adjustable from –9dB to +9dB in 3dB steps relative to the default 0dB setting. There are multiple choices for input impedance and adjustable input capacitance for both MC and MM modes.

I performed a complete set of measurements with my Audio Precision SYS2722 system using one of the single-ended phono inputs and both the phono stage's single-ended and balanced outputs, then repeated some of the tests with the preamplifier switched into the circuit. Most of the measurements were performed with the input set to MM, the gain set to its central, 0dB level, and the input capacitance set to 100pF. The lowest noise was obtained with the Audio Precision's signal generator ground floating and a separate grounding wire running from the PH-1000 input's ground terminal to the analyzer's chassis. I repeated some tests with the input set to MC mode and with the balanced phono and line inputs.

All the PH-1000's inputs and outputs preserved absolute polarity in both MM and MC modes through both the single-ended and balanced outputs. In MM mode with impedance set to 47k ohms, I measured 44k ohms at 20Hz and 1kHz for both balanced and unbalanced inputs, dropping to 20k ohms at 20kHz. In MC mode, the single-ended input impedance with the control set to "1000" was 1021 ohms at 20Hz, 998 ohms at 1kHz, and 992 ohms at 20kHz. With the control set to "100," the impedance was 104 ohms at 20Hz, 102 ohms at 1kHz, and 106 ohms at 20kHz. Set to "10," the impedance ranged from 13 ohms at 20Hz to 11.6 ohms at 1kHz and 20kHz. The balanced phono input supported only MC mode. Its input impedance defaults to 470 ohms and has a maximum setting of 4700 ohms. The measured impedances were close to the single-ended values, with the exception of 4700 ohms, where I measured 2400 ohms (1200 ohms per phase).

The PH-1000's output impedance is specified as 100 ohms unbalanced and 150 ohms balanced. I measured the balanced output impedance as 248 ohms in both Stage and Preamp modes from 20Hz to 20kHz. The unbalanced output impedance in both modes was 103 ohms at 1kHz and 20kHz and a still-low 208 ohms at 20Hz. The headphone output impedance was 40 ohms at 20Hz, 3.4 ohms at 1kHz and 20kHz.

The voltage gain is specified as 40–65dB, depending on the mode. In MM mode, with the output set to Stage, the measured gain was 42.2dB at both the balanced and unbalanced outputs with the gain set to –9dB, 51.2dB with the gain set to 0dB, and 60.2dB with the gain set to +9dB. The gain in MC mode set to 0dB was 65.4dB for both single-ended and balanced inputs. Switching to Preamp mode with the "Low" setting reduced the maximum gain by 6dB. With the Preamp "Hi" setting, the maximum gain was 8dB higher than in Stage mode.

RIAA correction was superbly accurate, with excellent channel matching (fig.1, blue and red traces), rolling off at ultrasonic frequencies, reaching –3dB at 41kHz. With the subsonic filter engaged, the response rolled off sharply below 35Hz, reaching –3dB at 19Hz (cyan and magenta traces). Turning on Enhanced mode increased the level in the midrange by 0.7dB (green and gray traces) and boosted the output above 10kHz by a maximum of +6dB between 40kHz and 50kHz. This would appear to be implementing the so-called Neumann 4th pole modification of the original RIAA curve.

222GoNo1000fig1

Fig.1 Gold Note PH-1000, MM, Stage mode, response with RIAA correction into 100k ohms (left channel blue, right red), with subsonic filter (left cyan, right magenta), and in Enhanced mode (left green, right gray) (1dB/vertical div.).

Compared with RIAA (fig.2, red traces), the various equalization options offer a wide range of modified responses (blue and green traces). The most extreme of these is "Telefunken," which peaks at 15dB at 11kHz compared with RIAA, "Columbia," which is –8dB at 10Hz and –3dB at 20kHz, and "Old RCA," which is +6dB at 10Hz and –2.5kHz at 1kHz.

222GoNo1000fig2

Fig.2 Gold Note PH-1000, MM, Stage mode, response with RIAA correction into 100k ohms (left channel gray, right red) and with 8 of the 18 alternate EQ settings (left green, right blue) (2.5dB/vertical div.).

Channel separation was superb at around 90dB in both directions across the audioband. Spectral analysis of the Gold Note's low-frequency noisefloor with it set to MM and 0dB gain (fig.3) indicated that both random noise components and power supply–related spuriae were very low in level. The PH-1000's unweighted, wideband S/N ratio, measured in MM mode with the unbalanced input shorted to ground and the gain set to 0dB, was an excellent 83.8dB in both channels, referred to an input signal of 1kHz at 5mV. Restricting the measurement bandwidth to 22Hz–22kHz increased the ratio to 87.2dB, while switching an A-weighting filter into circuit gave a further increase to an astonishing 91.6dB. Increasing the gain by 6dB reduced the S/N ratios by the same 6dB, while reducing the gain by 6dB increased the ratios by 3–5dB. In MC mode with 0dB gain, the S/N ratios were lower but still good, at 67.9dB (unweighted, wideband), 70.5dB (22Hz–22kHz), and 74.9dB (A-weighted), these all referred to an input signal of 1kHz at 500µV.

222GoNo1000fig3

Fig.3 Gold Note PH-1000, MM, 0dB gain, Stage mode, spectrum of 1kHz sinewave, DC–1kHz, for 5mV input (left channel blue, right red; linear frequency scale).

The Gold Note's overload margins were affected by the gain setting. In MM mode with the gain set to 0dB, the margin ref. 1kHz at 5mV was a good 15.1dB at 20Hz and 1kHz but dropped to 3dB at 20kHz. Setting the gain to –6dB reduced the margins by 6.5dB, while setting the gain to +6dB increased the margins by 6dB. In MC mode, the overload margins were 20.8dB at 20Hz and 1kHz and 8.6dB at 20kHz, all ref. 1kHz at 500µV. These margins were calculated from when the THD+noise percentage reached 1% and were equivalent to the PH-1000's output level in Stage mode reaching just over 10V RMS.

Distortion was very low. In MM mode set to 0dB gain and with a 1kHz signal 6dB higher than the nominal MM reference level (fig.4), the highest-level harmonic was the second, at –76dB (0.015%). Though other harmonics can be seen, these all lie at or below –90dB (0.003%). Distortion was even lower in MC mode, with the second harmonic lying at –82dB (0.009%), this with a 1kHz signal 6dB higher than the nominal MC level of 500µV. These spectral analyses were taken with the PH-1000 driving the high 100k ohm load. Commendably, reducing the load impedance to the current-demanding 600 ohms didn't increase the levels of the distortion harmonics.

222GoNo1000fig4

Fig.4 Gold Note PH-1000, MM, maximum gain, spectrum of 1kHz sinewave, DC–10kHz, into 100k ohms for 10mV input (left channel blue, right red; linear frequency scale).

Intermodulation distortion with an equal mix of 19kHz and 20kHz tones, with the gain set to 0dB and at a peak input level equivalent to 6dB lower than the overload margin in this region, resulted in the second-order difference product at 1kHz lying at –47dB (0.5%). Reducing the input level by 6dB dropped the 1kHz product to –54dB (0.2%, fig.5).

222GoNo1000fig5

Fig.5 Gold Note PH-1000, MM, 0dB gain, Stage mode, HF intermodulation spectrum, DC–30kHz, 19+20kHz into 100k ohms for 25mV peak input (left channel blue, right red; linear frequency scale).

Turning to the balanced line input, which has no EQ, gain, or input impedance settings: The gain in Stage mode was 0.76dB at the balanced outputs and 0.43dB at the single-ended outputs. Preamp mode with the volume control set to its maximum increased the gain by 8dB. The Line input preserved absolute polarity, and its input impedance was a usefully high 52k ohms. The line input's distortion was very low, with the second harmonic the highest in level at –96dB (0.0015%, fig.6).

222GoNo1000fig6

Fig.6 Gold Note PH-1000, Line input, Stage mode, spectrum of 1kHz sinewave, DC–10kHz, at 1V into 100k ohms (left channel blue, right red; linear frequency scale).

The Gold Note PH-1000's performance on the test bench reveals that it is a well-engineered phono preamplifier, especially considering the enormous range of adjustments it offers. Both distortion and noise are very low in level. While its overload margin at the top of the audioband is relatively low, this can be increased by increasing the phono stage's gain without incurring any significant noise penalty.—John Atkinson

COMPANY INFO
Gold Note Italy
US distributor: Rutherford Audio
14 Inverness Drive East, Unit G-108
Englewood, CO 80112
ARTICLE CONTENTS

COMMENTS
johnnythunder1's picture

The aesthetics, engineering methodology, Michael Fremer's existence, the price, the country of origin, its comparison to other phono stages costing 10-50x less, and other random complaints hasn't brought out the trolls yet.

MatthewT's picture

You know what they are going to say, too.

kg's picture

Given the unprecedented nature of the current events, I advise you to proceed with utmost caution, my dear friend.

MatthewT's picture

Elaborate on this post.

Jack L's picture

Hi

You've said it: the invasion of Ukraine by Russia yesterday, killing 57 & wounded 160 people as of today as per BBC News

Jack L

JHL's picture

We've known for decades of the difference between data and sound. For the sake of great sound I hope this publication redevelops this fundamental dichotomy. It is real.

Many assume data speaks for sound.

Jack L's picture

Hi

Agreed. But not for yours truly: data & sound go the extremely polarized directions.

Standard bench test data are obtained by feeding pure sinewaves, square waves or triangular waves into the component under test. This I would call it static test.

Music signals are not pure sinewaves at all: comprising basic sinewave plus multi orders of harmonics, ever dynamically changing.

So it is therefore comparing apple to orange - irrelevant ! So how can we "assume data speaks for sound" ??????

If you get the chance to look at the 3-D waveforms of a realtime music signal, like I have, you will see how complex would be a music signal, ever dynamically changing.

May I suggst you to read up papers on the complex multiple 3-D positioned visualization of music signal. to learn more about it, e.g.

"3D musical notation - providng visual cues for musical analysis".

Listening, not data alone, is believing

Jack L

JHL's picture

...but I can't find a place to interject in an argument against everything simultaneously.

Jack L's picture

Hi

Apparently most money gone to the 'unique' feature of RIAA curves (40+) adjustment to tailor-match old/new LP labels.

"Deutsche Grammophon records used the DG/Teldec curve well into the stereo era, and that's why DG records tend to sound dull played back using RIAA." qtd M.F.

I am not so sure of above quote appliable to my DGG collection. In fact, quite a few my DGG LPs sound so so good that I've used them as my sonic reference: open, balanced & livelike.

Just quote 3 excellent sounding DGG LPs:-

(1) Beethoven No.1 Piano Concerto/Arturo Michelangeli/Vienna Symphony/Carlo Goilini. Live performance recording 21/9/1979
The piano sounds so crystal-transparent, best of all my piano LPs

(2) Richard Strauss: Also Sprach Zarathustra/Boston Symphony/William Steinberg 1971.
The performance starting sub-bass notes (20Hz?) solidly crawl toward me, followed immediately by kettle drum beats - sharp & powerful !!!!!

(3) Strawinsky: Le Sacre du Printemps/Berlin Philharmonic/Herbert V Karajan 1977. Powerful sharp percussions !

Only played throu my home-brew phono-preamp (MM input/non-adjustable passive RIAA). I got no problem sonically with all my DGG LPs at all.

Listening is believing

Jack L

remlab's picture

WHAT IS THE WORLD COMING TO!!

Jack L's picture

Hi

Yes, my first glance at the compact enclosed power supply hinted me it should be a wall wart type switch mode power supply !! Nooo good for any analogue amps, let alone phono preamp, IMO.

Yes, compact, handy & cheap but it emits EMI/RFI noises into the amp. I'd never use such SMPS in any of my audio amps. Get an external analogue linear power supply would be the way to go.

Jack L

Archimago's picture

Dunno man. This fear of SMPS as being noisy doesn't mKe much sense these days. Even some of the cheapest SMPS wall warts don't emit much RF/EMI any more.

Would love to see what evidence there is for such a belief and with what power supply and analog gear susceptible to this.

Jack L's picture

Hi

Really? Your home-brew science or your imagination ?

I tested with my digital wideband EMI & powerline noise analyser. It shows RF noise surge in the powerline powering any digital devices using wall warts or similar SMPS.

This physics !!!!!!!

Jack L

Archimago's picture

Yes, it's physics.

And IMO you're worried about imaginary ultrasonic stuff.

Show me otherwise cuz I don't know anyone who is able to reliably tell a difference. (People claim all kinds of things like yourself but have nothing to show for it.)

Jack L's picture

Hi

It's your call, pal.

You challenged me SMPS does not emit RFI/EMI/powerline noises. Now I tell you again such powerline noise DO exist as shown on the screen of my digital wideband powerline noise & EMI analysis.

Frankly, you don't apparently even know such commonly used instrument to analyse poweline noises do exist at all.

Be my guest if YOU or whoever lend a deaf ear. None of my business.

Jack L

tonykaz's picture

Canada is now under Martial Law

Ukraine isn't joining NATO, no bullets flying

This Italian buggy whip gets barely noticed.

Tony in Florida

MatthewT's picture

Haiku.

Glotz's picture

Almost.. But there is no beauty in those words.

Archimago's picture

I'm sure we'll this sorted by Spring Break! Come visit. ;-) Although I think it's much nicer this time of the year down in Florida.

Jack L's picture

Hi

What "spring break" ?

You mean March break when school/universities close down a week or more provding private times for students' families.

Yes, there is a "family day" coming Monday, the 3rd Monday every February, a provincial public holiday with salary fully paid.

Jack L

Archimago's picture

It's on the school calendar from March 14-25 for the families with kids.

Jack L's picture

Hi

Rumour or misinformation-on-line ?

So called "Freedom Convoy" at Ottawa, Canada capital city, is already done like dinner a couple of days ago. Those behind-the-seen financiers, including a few from USA, for such illegal "convoy" are already tracked down & their convoy monies are already frozen.

We should worry more about the Canada/USA border road block by the trucks due to their drivers not yet vaccinated. 70% of goods trades Canada/USA is done by trucking thru the border every day !!!!

We already felt the pinch: our grocery & food prices soar up like nobody's business !!!

Thanks to those drivers' "freedom" conscience !!!

Jack L

tonykaz's picture

Yes, we have that problem with our legacy press. ( not Stereophile though )

One of the Canadian MPs reported to his YouTube Channel that Parliament has been suspended.

The Industrial Report on the Trucking Industry ( USA ) reveals that we have about 2,000,000 Live Breathing Truck Drivers today. We have 3,500,000 Semi Trucks available. ( an acute driver shortage )
Additionally, we have all the West Coast Entry Ports at FULL capacity with a critical shortage of derage drivers ( the short range drivers that haul the Containers from the Port to locations within 50 miles ).

Truck Drivers are mostly Unionised, 80% are small companies of 6 or less. Politically, Drivers are considered the "Deplorable" Class ! They stay connected thru modern communication devices. Most Over the Road Rigs are fully Internet Capable and have a wide range of connectivity tools. The Canadian Freedom Convoy is the 1st of a Global Series of these types of Events. Another One is now forming up to go from California to Washington. Expect the Farmers to share in this as they typically operate two or three Semi Truck rigs.

Heavy Trucks and Diesel engine related Industries are the World I lived in so I still follow these developments.

It's said and thought that the Stores have 3 Days of goods, if the Trucks Stop rolling -- all hell breaks loose .

It's time to be careful

Tony in Florida

Briandrumzilla's picture

It is an explosioney, but mostly peaceful war.

tonykaz's picture

Tony in Florida

Kursun's picture

A phono preamplifier priced at $12.000 with very very poor overload margin? Doesn't make sense at all.

Jack L's picture

Hi

Well, it makes tons Money Sense to the Italian manufacturers/vendors. Profiteering I would call it.

Italian leisure goods are always expensive, including audios.

I still recall I spent some US$40, 1/5 of my monthly salary for a Valentino silk tie some 40 years back.

For such money, I've gone for French goods: Lacoste (the green Alligator logo) T-shirts of diffenent colours, soft-leather sneakers, etc.

For my pocket wallet, Louis Vuitton of course ! Genuine soft leather made with its serial number inside itm, like any audio components !!

Jack L

Kursun's picture

Well...
If a product is expensive but good I wouldn't object.
I have a 30 year old Lacoste sweatshirt that I still wear.

But, if a product costs $12.000 and displays a sub-mediocre performance, this is a problem.

Jack L's picture

.

volvic's picture

It is priced six times higher than the PH-10, I wonder is it six times better? This is a serious question as the PH-10 has garnered rave reviews from others and appears to offer similar flexibility. Curious.

Anton's picture

The compulsion to mix politics into Hi Fi is a classic sign of impending dementia.

Just saying.

tonykaz's picture

are you angry relating to the median age of us 33.3 people ?

Your opinion is probably accurate, vinyl people are fully captured by the hobbies of our post WW11 youth and a certain fondness of "I like Ike" memories.

Your diagnosis should include neurosis & psychosis which are the prevailing qualities of our Reviewed Gear buying readership. ( myself included )

Tony in paradisiacal Florida

Glotz's picture

Totally true. Fucking wrecking the last frontier of truth. Fuckers.

Jack L's picture

.

hollowman's picture

... the extensive Measurements section for a type of product that does not get metric'd often in audio journalism. AUDIO mag used to do something similar for phono products -- the late 70's - 1980s IIRC.

Glotz's picture

It was overwhelmingly positive, but no one has anything (but negative shit) to say.

Anton's picture

1) It gave me a great sense of feel for the device.

2) It enlightened me further regarding vinyl playback history.

All good. Better than good!

Out of my budget, but I am happy it exists.

ozan2022's picture

I purchased PH1000, PSU 1250, and Tube 1210 few months ago. First I used PH-1000 as it is then added the PSU and could not believe the improvement. And then I added the tube output stage again a substantial improvement but the PSU is a tremendous improvement. Highly recommend it.

Anton's picture

Thanks for the perspective.

Spartachino's picture

They stole the PH-1000 name from Victor Laboratory PH-1000 Ceramic Headshell.copyright infringement and disrespect

Spartachino's picture

Why would I buy a 12K device with crap bottom end?

Only the somewhat polite bottom end disappointed

David Mansell's picture

The "Teldec EQ" myth is only furthered by Jim Austin's footnote. PSpatial are in business to sell software (and some expensive hardware) to convert non-RIAA encoded LPs to RIAA so it pays them to spread the notion that there are loads of non-RIAA records out there, even into the stereo era.
You would be better served, Jim, by consulting Peter Copeland's classic "Manual of analogue audio restoration techniques". Pspatial misquote him about the meaning of the inverted triangle symbol on German (and other European) record labels. They say he says that it means the use of the CCIR equalization time constants, whereas they say it means the use of the so-called "Teldec equalization". What Copeland in fact writes is that it means the use of the RIAA (75, 318 & 3180 microseconds) equalization ; and that is what it does mean. Deutsche Grammophon had converted to the use of the RIAA equalization long before 1959 or even the 1957 DIN proposal to use 50, 318 & 3180 microseconds. You can find the inverted triangle on German Decca LPs (made by Teldec, the joint Telefunken and British Decca record manufacturing company) in 1955. You will also find it on LPs manufactured in the Netherlands (Philips), East Germany (Eterna), Romania (Electrecord)and even the Soviet Union (Melodiya) where it means "uses RIAA encoding". When stereo came along both the German Teldec companies, Telefunken & German Decca changed to the interlocking circles symbol (which means RIAA stereo) for a couple of years, but they both changed back to the inverted triangle in about 1961 for promotional reasons. In fact Telefunken used the inverted triangle until they ceased trading in 1982. All these records used RIAA encoding.
I have mono (inverted triangle) and stereo (interlocking circles) versions of the DGG LP of Sviatoslav Richter's recording of the Schumann piano concerto. Yesterday I played them both through my Audio Research preamp (RIAA phono) and they both sounded absolutely fine and the instruments were timbrally identical. I have lots of pictorial evidence to back up my assertions but it is not possible to post it here.

Michael Fremer's picture

For this clarification. And the wealth of accompanying information.

X