Marten Parker Trio Diamond Edition loudspeaker Associated Equipment

Sidebar 2: Associated Equipment

Analog source: Linn Sondek LP12 turntable with Lingo power supply, Linn Ekos tonearm, Linn Arkiv B cartridge, Channel D Seta L phono preamplifier.
Digital Sources: Roon Nucleus+ file server with HDPlex 200 linear power supply; Ayre Acoustics C-5xeMP universal player; PS Audio PerfectWave DirectStream D/A processor and MBL N31 CD player/DAC, Ayre Acoustics QA-9 A/D converter.
Preamplifier: Pass Labs XP-32.
Power amplifiers: Parasound Halo JC 1+ monoblocks.
Cables: Digital: AudioQuest Vodka (Ethernet), AudioQuest Coffee (USB), DH Labs (1m, AES/EBU), Esperanto (S/PDIF). Interconnect: AudioQuest Wild Blue (balanced). Speaker: AudioQuest K2. AC: AudioQuest Dragon Source & High Current, manufacturers' own.
Accessories: Target TT-5 equipment racks; Ayre Acoustics Myrtle Blocks; ASC Tube Traps, RPG Abffusor panels; AudioQuest Niagara 5000 Low-Z Power/Noise-Dissipation System (amplifiers) and AudioQuest Niagara 1000 Low-Z Power/Noise-Dissipation System (source components). AudioQuest Fog Lifters cable supports. AC power comes from two dedicated 20A circuits, each just 6' from breaker box.
Room: 20' (left side), 25' (right side) × 16' × 8' —John Atkinson

COMPANY INFO
Marten
US distributor: VANA Ltd.
Nesconset, New York
(631) 960-5242
ARTICLE CONTENTS

COMMENTS
JRT's picture

I suggest (edit: I removed my erroneous suggestion).

John Atkinson's picture
Fixed. Thanks for the eagle eyes.

John Atkinson
Technical Editor, Stereophile

JRT's picture

It was intended as constructive criticism.

Keep up the good work.

MZKM's picture

in a $37,000 speaker. Doesn’t appear to be from a cabinet vibration, is it from the passive radiators?

And excuse me asking, but if the speaker is on a wheeled dolly, why can’t you fully rotate it to measure +/-90°? I couldn’t understand the explanation.

Looks like the voiced it well by adding a dip at 3.2Hz to combat the wide off-axis dispersion.

The bookshelf Duo measured around it’s stated sensitivity, so odd that this is so much lower than spec and barely higher than the bookshelf, the tweeter (BD 25-6-258?) is likely not the limiting factor.

JRT's picture

I suspect that is an internal modal resonance, a standing wave. The apparent path length is a little longer that the internal height because the path includes delays and detours around internal bracing, woofer chassis, suspension and motor structures, passive radiator chassis and suspension structures, etc.

Speed of sound is oft quoted at 68 degrees Fahrenheit at approximately 343_m/s, and is 344 at 71, 345 at 74, 346 at 77, and is primarily dependent on air temperature. Air temps inside the enclosure will be warmer than room air while the loudspeaker is operating.

(343)/(140*2)= 1.225 meters
(344)/(140*2)= 1.229 meters
(345)/(140*2)= 1.232 meters
(346)/(140*2)= 1.236 meters

You can see some associated resonance in the passive radiator nearfield response, and more resonances an octave higher. The second order resonance is not showing in the impedance curve, perhaps because the geometry is not imparting a pressure node on the woofers where it would feed through the motor and be reflected in the impedance Though the lower woofer does appear as though it should be near a pressure node, unseen internal structures may be dictating something else.

You won't see that in a PR loaded subwoofer where internal paths are small relative to wavelength. But you will see it where PRs are utilized to load midwoofers operating at higher frequencies, shorter wavelengths (shorter than subwoofer wavelegths) in the taller enclosed air volume of a floor standing loudspeaker of a design lacking internal damping located in or near the velocity node positions of the internal modal resonances of the enclosure. Suitable damping is key, essentially using internal airflow resistance in those velocity nodes, effective at the frequencies of interest, but almost invisible at lower frequencies nearer the PR tuning. An example would be some SAE F13 sheepswool techical felt (maybe in combination with some Roxul Rockboard 80) sandwiched between a closely spaced pair of windowed shelf braces and some grill mesh or perforated steel for added support located at roughly 1/3 of the internal height where it would damp fundamental and second order standing waves in that path.

John Atkinson's picture
MZKM wrote:
excuse me asking, but if the speaker is on a wheeled dolly, why can’t you fully rotate it to measure +/-90°? I couldn’t understand the explanation.

The problem stems from the fact that at angles greater than 45 degrees, there were reflections from nearby surfaces in my listening room that compromised the measurement.

John Atkinson
Technical Editor, Stereophile

noamgeller's picture

Dear John Atkinson, at the first paragraph you wrote "at 6990$ those speakers aren't inexpensive..." and I was like, wow finally some sense! And then at the second page of the article it turned out to be 36,990$!!! And then I was like, ho, right.

Jim Austin's picture

The $6990 speakers were Oscar Duo's from a previous review. As JA describes in the early part of the article, we were first planning to review a much cheaper version but ended up with the version with the diamond tweeter, which is much more expensive. Very likely, the cheaper version is almost as good.

Jim Austin, Editor
Stereophile

noamgeller's picture

I read the article again... I got it now... Would have been nice thou at 6995$ oh well :)

Kursun's picture

New loudspeakers come and go, often at exaggerated prices. 35 Years ago I had secured a pair of Yamaha NS-1000M's. For me they are still the best loudspeakers money can buy. Provided of course they are driven by first rate, preferably Class A amplifiers. Funny, their list price was only $1500.

JRT's picture

Technology has advanced. You should listen to some of the newer better loudspeakers.

Kursun's picture

Not as much as you think...

Homer Theater's picture

Changes are RADICAL today compared to the 1970s when the NSM-1000M was designed. Materials improve, understanding of the physics improved, computer modeling/design software has made HUGE, nearly unimaginable changes compared to what was possible in the 1970s. Crossover design is massively better today than 50 years ago. Today's high quality electronic components did not exist in the 1970s. NON-DISCLAIMER: This is written by someone who recommended Yamaha NSM-1000s to three different friends in the 1970s who all loved them after their initial freak-out at the cost of them compared to the guy in the parking lot with a van full of big $25 speakers. I was well aware of how good NSM-1000s were in the 1970s. Why didn't I have NSM-1000s of my own? I was already a high-end idiot with speakers that cost 2.5 or 3 times more than NSM-1000s.

Kursun's picture

Computer software only mimics the principles and formulas published half a century ago.
Do you mean no greatly engineered products, structures or buildings could be built before computers?
As a structural engineer, part time professional software developer and an amateur loudspeaker system designer I tend to disagree. Nothing could be further from the truth.

BTW, Yamaha NS-1000Ms were not designed as an upgrade for white van loudspeakers.
They were produced as reference monitor speakers for highest quality recording studios worldwide and discerning audiophiles, regardless of price. They have highest technology in design and materials.

Kursun's picture

Loudspeaker enclosures are still designed with the formulas given by Thiele & Small (published 1960-1970). Crossovers are still designed by formulas given by Butterworth, Linkwitz-Riley, etc (equally old tech).
Actually, not much is new. (Except greedy manufacturers...)
And new doesn't always equal to better.
If you'll ever listen to Yamaha NS-1000M's, you'll understand what I mean.

SET Man's picture

Hey!
JA: "I kept being tempted to play music loud, though this meant that the huge bass drum hit 12 minutes before the end of Part Two of Gerontius scared the heck out of my cats, who were dozing on top of the speakers."

Reading that gave me a good chuckle, only cat owners would understand. Reminded me of my old cat, he used to hangout on my speakers also. Luckily he was careful getting up and down so I didn't have to worry about he tipping my speaker over.

X