Synergistic Research PHT

Synergistic's PHT ($199/set of two, footnote 1) is a very tiny, tweezer-ready HFT designed to placed atop a phono cartridge, and is marketed with a nod and wink: "grown in California, legal in all 50 states" (PHT is pronounced pot). Analog vets might remember Apature's line of moving-coil cartridges from the 1980s, which included the models Panama Red, Maui Blue, and Koce (which was white). Think I'm handing you a line? I've got a Koce here.

The PHTs "tune" the system directly at the source. Of course, a cartridge is probably the most "tuned" component of an analog audio system. Cartridges are tuned for compliance, "tuned" on the basis of body and cantilever material, etc. Adding another tuning element isn't exactly a radical idea. Synergistic supplied two differently "tuned" PHTs, one blue ("Blue Velvet") and one purple ("Purple Haze"), though Synergistic's Ted Denney says they can be made in an endless variety of "flavors"; he plans to launch a "subscription series."

The Cobra tonearm of my Continuum Audio Labs Caliburn turntable doesn't grant access to the cartridge's body, so Denney stuck a blue PHT to one of the screws securing my Lyra Atlas cartridge to the Cobra's headshell—but not until I'd first played "Lullaby of Broadway," from a reissue of Tony Bennett's At Carnegie Hall (2 LPs, Columbia/Analogue Productions AAPP 823). This album's sound is astonishing: a huge, deep, wide, airy soundstage with precise image focus and what I'd thought was the highest level of transparency.

The addition of Synergistic's HFTs and FEQs had enhanced the sound, but adding that blue PHT produced an ear-popping, Cinerama-like, wraparound soundstage, and an overall sound even less tethered to the speaker positions. The image focus was increased without producing razor sharpness, and there was greater front-to-back separation of sources within the soundstage.

In "All the Things You Are," Bennett's voice jumped forward in three-dimensional relief—almost alarmingly—while the xylophone hovered more convincingly well in front of the speaker plane. Decays were longer, and the backgrounds they faded into were "blacker." The applause produced layered, contoured, front-to-back of the room depth. It was easy enough to remove the PHT and, of course, reset the Lyra's vertical tracking force (VTF). It still sounded great, but with the blue PHT in place the sound was clearly better overall, with improved focus, three-dimensionality, and transparency. A purple PHT produced a less intense but equally noticeable change, mostly in increased midband richness and solidity.—Michael Fremer

Robert Deutsch auditioned the PHT in October 2016 (Vol.39 No.10):
Let's face it: In addition to vinyl's sonic benefits, much of the satisfaction of playing LPs comes from the opportunity to tweak the various parts of one's LP player for optimal sound quality. (There are opportunities for tweaking digital playback, but not nearly as many.)

When I replaced my long-in-the-tooth Linn Sondek LP12 turntable and Ittok tonearm and AudioQuest cartridge with Acoustic Signature's WOW XXL turntable and TA-1000 tonearm and Soundsmith's Zephyr MIMC cartridge (footnote 2), the sound quality of my vinyl playback took a major step forward. But I suspected, from previous experience with tweaking record players, that further improvements were possible. To that end, I replaced the WOW's stock phono cable with a Nordost Valhalla 2 Reference, replaced its stock turntable mat with Herbie's Way Excellent II mat, and added Harmonic Resolution Systems' ADL record weight. With all these tweaks in place, my records have never sounded better.

But was that it for worthwhile phono tweaks? Not long after, I saw an ad for the Synergistic Research PHT ($199/pair), a "micro-transducer" that you stick atop a cartridge or headshell, and that Synergistic says produces all kinds of audible improvements. (PHT, which the company pronounces as pot, stands for PHono Transducer.) If only a fraction of their claims were realized, I thought, a PHT could be what my record player needed. I had doubts about whether something that changes the resonant characteristics of a cartridge would necessarily improve—as opposed to just change—the sound, but our own Michael Fremer, who knows a thing or two about phono playback, wrote that the PHT "produced an ear-popping, Cinerama-like, wraparound soundstage, and an overall sound even less tethered to the speaker positions." Mind you, that was in the context of Mikey's ultra-high-end system. Would I hear a similar effect in my more modest system? I had to give it a try.

Synergistic sent me four PHTs to try, each finished in its nominal color: Blue Velvet, Purple Haze, Black Widow, and Green Dream. Each is also said to belong to a different "strain" of PHT, known for producing different effects (footnote 3). The devices themselves are tiny—each PHT is smaller than the head of a cartridge-mounting screw (see photo). An even smaller bit of White Tack adhesive (provided) attaches the PHT to the top of the cartridge. I have no idea what the PHTs are made of—and designer Ted Denney was not forthcoming.

With each color of PHT, I first listened to a track, then placed the PHT atop the cartridge, compensated for the PHT's weight by adjusting the tonearm counterweight, and listened again. (Synergistic recommends using only one PHT per cartridge). I then used the little dab of White Tack to more securely attach the PHT.

In every case, the sound improved: soundstages were deeper and wider, aural images more precise, dynamics more startling. I didn't spend a lot of time comparing the effects of the different versions—just enough to be convinced that there were indeed audible differences among them and that none of them made the sound worse, the latter seeming possible had the products' effects been due to just random changes in cartridge resonance. My favorite was the Black Widow, but I quite liked the Blue Velvet, too. Using the White Tack to secure each PHT to the cartridge always heightened the product's effect.

I talked to Denney about the technology behind the PHT, but learned little beyond the fact that the effect has to do with resonances, is akin to "tuning," and is proprietary. Not very satisfactory answers for those with a scientific bent, but, as always, the proof of the pudding is in the eating—and this particular pudding tastes delicious. I think $199/pair for the PHTs, with money-back guarantee, is well worth it.—Robert Deutsch

Footnote 1: Synergistic Research, 17401 Armstrong Avenue, Suite 102, Irvine, CA 92614. Tel: (949) 476-0000. Web:

Footnote 2: See my review of this system in the February 2016 issue.—Robert Deutsch

Footnote 3: To read that sentence out loud, in accordance with Synergistic Research's recommended pronunciation of "PHT," is to get the joke.—Art Dudley

Anton's picture

We used to be able to buy that tweak, literally, for a penny!

I wonder if Mike has tried them on his new Swedish arm.

tonykaz's picture

Any old mass will do.

One should have an understanding of cartridge compliance and Arm mass to do a proper calculation. Simply adding mass is guesswork, a person could also remove mass by using Alum. screws or any of the other established methods ( tricks of the good old days ).

At my Esoteric Audio Salon ( mid 1980s ) I had an Accessories Wall stocking items like this Arm twerking stuff, it was profitable ( seems it still is ).

Tone Arm & Phono cartridge tweeking is getting quite rare now-a-days, I doubt that anyone is trying to make any money from any of it. Let them have their fun, it's harmless. ( as far as I can tell ) Although, it could be demonstrated as evidence for a Divorce Attorney.

Tony in Michigan

calaf's picture

I wonder what Mike and Robert have been smoking...
(sorry, could not resist)

Glotz's picture

MF and RD have echoed each others findings, and I trust them. Remember, it's about the listening, not the suppositions about what should or shouldn't work. There is much we do not understand, right now.

It is worth a try for sure, and there is a money back g'tee, sooo....

Anton's picture

Which color tribe will you choose?

Solarophile's picture

You could buy some good stuff for $200 that actually DO things.

Why ar things like this even being reviewed? Michael Fremer ssometime will rip some audio for comparisons. Why not do something like that with and without this and see if it sounds different. If something is unlikely to work, shouldn't we try working a little harder to find the truth?

georgehifi's picture

Over on the Audiogon forums, the voodoo'ist (or shills) swear that their systems are transformed using their >$100 A.C. mains fuses as well, many stating that they are also directional and can be clearly heard and makes a big impact!!! There's one born every minute.

Cheers George

PaulMG's picture

Is there a defeat device integrated allowing only to work within the temperature range of the platter's bearing controlled by a most sensitive air conditioning?

Oldsport's picture

The added mass aspect might affect things. I wish one of you fine fellows would throw one of these little critters on your digital tracking force scale and tell us how many grams it weighs. Thanks.

Robert Deutsch's picture

In our respective writeups on the Synergistic Research PHT, Michael and I both noted that in evaluating this product we compensated for its possible effect on VTF, by adjusting the arm's counterweight. In response to the question about "how many grams it weighs," I've just weighed it (including the small amount of adhesive), and the answer is 0.08g.

Anton's picture

Apropos of nothing, that's 1,135,000 dollars per pound.

For the same price as the PHT, you could buy 5 grams of gold.

By weight, these would be a .4 carat diamond, which goes for under 600 bucks if an emerald cut.

I wonder if you could mount three in a ring for an audiophile engagement ring?


Catcher10's picture

I am sure I get the same results using the Soundsmith EZ Mount Cartridge Screws.....Which cost me $35 for the set. Same process of adding mass.....

Glotz's picture

With ZERO experience actually LISTENING to the product's effects.

No, you don't have an opinion, just a lot of jaded conjecture.

Everyone is SURE they are getting the same effects from other methods, but they haven't actually COMPARED them. Pffft.

Why even post? To show your contempt for all things one doesn't understand? YEAH.

Anton's picture

Tell us about all the cool things you have stuck to cartridges and compared the sound of!

I bet you have quite a list, being a curious audiophile, and all.

On arms with detachable headshells, I love playing with different headshells and mountings.

I do admit to have having never met a headshell or screw that performed differently depending on what color drop of nail polish I dropped on top of it.

tonykaz's picture

Your drops are not "tweeser ready" are they? Hmm!

Jason Stoddard just wrote a few words about sceptic writers, like you ( and me, for that matter ). I wonder if you have any thoughts about that sort of Schiit commentary ?

Tony in Michigan

Glotz's picture

There are several great products and materials that flat-earthers laughed at for years... like carbon fiber. Now several companies, like Ortofon, make carbon fiber headshells.

Anton's picture

That's your list of the cartridge and tone arm tweaks you've investigated?

Do you even play records?

Have you tried Ortofon's carbon fiber headshell?

Glotz's picture

It was one example directed at modifications in general. The Oyaide headshell is cheaper and looks more modern. A lot, if not most work. I've used several (BDR, Arche), and I've have had years of experience rebuilding turntables, etc.

It's not about personal experience here, it's about the product under review, by two people that have been doing it for a long time.

(Nor is it about not misanthropic arguments about which online reader thinks he knows the most.)

Almost every one in here wants to cry bullshit without trying it out themselves. This is a very plausible follow-up based on an original review from ears I trust.

If the improvement on a respectable rig is worth it, so is the price... unless you want to machine it yourself (and 'it', the material in each of the 4 products, is proprietary).

The PHT works like a mini-tuning fork. It's effect changes based on material.

avanti1960's picture

could be swayed by some needle drop file downloads with and without device.
how about it?

Oldsport's picture

Thanks, RD, for weighing the SR PHT. Interesting. Though several times the weight I saw mentioned on SR's site, I would suggest that its weight is probably within the manufacturing tolerance of most any cartridge body. So, 'tain't likely the quantity of mass that is causing the effect. Perhaps more what that mass is doing in absorbing (and releasing?) vibration...

dmurphy1001's picture

Thank God somebody finally reviewed the PHT
now can I please unplug my digital clock and take the brick off of my amplifier????

AudioontheCheap's picture

I believe Mike on the Apature carts. Speaking of, they are quite elusive. I also have a Koce that came with a used TT I bought a couple of years ago.

Mike-or anyone else-do you have any specs for the Koce, particularly recommended tracking force, maybe with and without the PHT?

ejw's picture

I saw some PHT's for sale and found this review while doing some research, but it got me thinking...

If I had spent the amount of money on a system that MF has (or even RD) I would be VERY p****d that a $125 tweak could IMPROVE the sound! (Especially one not specifically designed for that system).

OK, I get that any change to the mass of the tonearm system, particularly at the cartridge/stylus end, is bound to change the characteristics.

However if I'm spending $1000's on a system I would EXPECT the manufacturer to get it as near perfect as possible (given a budget).

I can appreciate low-end or budget systems being improved by tweaks, but in the price range of MF's (and RD's) systems any tweaks SHOULD only degrade performance IF the manufacturer has done their job properly!

The same is true for tweaks to other components, such as speakers, cables, power supplies, etc.

I can see the case for some types of tweaks (e.g. room treatments) but there's no way PHT's or a Way Excellent Mat should be able to improve the systems used by MF & RD.

Just my $0.02 but if it was me I'd be giving Continuum, Lyra, Acoustic Signature, and Soundsmith a VERY hard time!

EgglestonWrks's picture

So stupid, I expected more from MF/RD

EgglestonWrks's picture

I have no affiliation with EgglestonWorks

Dr. Fuse's picture

I have just created a better product than the SR PHT. It is a very special and fragrant Phono Acoustic Resonance Transducer - PhART!

This is not just hot air - my PhARTs add MASSIVE RESONANCE, that cures midrange BLOOM, and flabby bass. It also adds a sniffable airiness and a whiff of the high end, whether your speakers are front- or rear-ported.

$198 for two PhARTS. THIS IS NO B*LLSH*T!