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Introducing Telos-audio


Telos Audio

Telos Audio Design offer several products designed to tackle audio and AV grounding noise, signal ‘phase’, and power supply issues. Jeff Linn, Telos-audio founder, designer, and avid audiophile has developed a unique and patented active grounding solution that removes the ‘noise’ that enters the audible electronics chain due to poor grounding on the signal earth line, that in turn connect to ‘dirty’ mains power earth, a poor ground reference for highest fidelity. No mains power grounding, even a dedicated ground spur is fully effective, and in most cases poor grounding prevents the highest audio efficacy. The product range focused on system earthing is called the ‘Ground Noise Reducer’ (GNR for short).

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Powering and correctly earthing digital streaming products is an area where Jeff Linn has achieved considerable design success. A simple to fit combined power improver and earthing product offers a cleaner digital stream for improved fidelity. Check out the ‘Macro G’ product range.


Telos Audio Click through

Ground Noise Reducer (GNR)

Telos Audio Macro G

Macro G

Telos-audio REVIEWS etc.

Positive Feedback on-line magazine, Issue 125, 20th Feb. 2023

Audio Ramblings and the Telos GNR 5.1 Plus+ Active Grounding Box

By Dave Clark

Full review: 

Audio Ramblings and the Telos GNR 5.1 Plus+ Active Grounding Box


Actually, never said this (before) but here it goes. Really don’t care how great you or others think your system is and how wonderful it reproduces music. Might be the greatest thing since sliced bread. And you might be the happiest listener ever. We did and were… but until you have heard what the Telos GNR products can do… you are really scratching just the surface of what is possible. So much more of your music is being obscured from the background noise that is just sitting there doing its thing. As good as it sounds, that is just a teaser. Not inexpensive for sure, but … these are components, not accessories. Components that are requisites to hear what is really there

Highly, highly recommended.

GNR V5.1 Plus+

Retail: $8000   (UK:  £6,795.00p)

‘Mono and Stereo’ GNR review

by D. Han

When I started my audio den some years ago, a number of audiophile friends shared to me that having your main electrical supply properly grounded is crucial in getting rid of unnecessary electrical noise in the audio system. I realized what they have shared to me was of great substance. Therefore, I decided it was necessary to spend some energy and monies into it. Thus, I have taken out one out of three phases from my electrical main to be dedicated to my audio den. This phase is isolated from all other electrical uses but only for my audio components. In addition to the main electrical grounding, this dedicated phase enjoyed two number of dedicated grounding; both comprised of pure copper strips to two number of pure copper rods planted at two spots, into the soil that is near to a drain. That was purposefully done so that the ground copper rods constantly planted in moist soil to improve the potency of the grounding. The above efforts resulted in a much quieter audio presentation, bigger soundstage, better imaging and density.

Later, Frank Voon introduced his wonderful creation, the Frank Power Bank to me. In short, it is an independent “shun reactor” for sudden and improved power delivery for any audio component in connection with it. He proposed to have the Frank Power Bank to be connected to the MCB and/or the ELCP of the electrical phase in the electrical distribution box. Thus, all audio components in that electrical phase will enjoy its benefits.  Suffice to say, I was so impressed with this product that I bought quite a number into my system. I will have more details to share about the Frank Power Bank in an upcoming dedicated review at Mono & Stereo.

And I thought I am done in term of electrical supply and grounding. Then, some audiophile friends shared to me the idea of having dedicated ground for the audio components that is independent from the electrical main. They recommended chassis grounding, input and output connector grounding, tonearm grounding and wherever it’s safe and possible for grounding. I said to them that I am interested to try. Sooner than I thought, I was introduced to the Entreq Grounding System.

Enter my First Dedicated and Independent Grounding System

The then local distributor, Swedish Statement Audio Boutique brought me the Entreq Tellus (Copper version) grounding unit and the recommended Entreq Eartha copper ground cables. Upon hooked up, I heard some differences in the audio system presentation. I noticed that there was a tad lower noise floor and that the soundstage width, height and depth improved. Everything seemed a tad clearer; images enjoyed a clearer definition, delineation and separation. To me, that whole experience then drew me to the importance of the added independent grounding for the audio components.

 The next level?!

The Silver version of Entreq Silver Tellus with its Atlantis Silver ground cables were a whole new level (I testified in advance). Upon their introduction into my audio system, I heard better articulation in the lower bass. The higher frequencies sounded cleaner, extended and airier. The above contributed to the naturalness in the presentation of stringed instruments such as violin, guitar and even the cello.

The game was later up another notch with the next introduction. The Entreq Cleanus which could be added to my power distributor, the Shunyata V-Ray 2 and ground connected to the Silver Tellus. Immediately, I noticed that the whole audio presentation enjoyed another level of lower noise floor. What were once in the foreground and blur enjoyed a certain clarity, definition, tangibility and density. What were subtle, remained subtle but enjoyed clearer role in the whole presentation. I think I am able to understand and enjoy the music better with the addition of the Entreq Cleanus in my audio system.

Ambition was raised!

Then, I thought my pursuit of a fine electrical supply and grounding for my audio system was at an end. That notion maintained until I met Jeff Lin, the Founder and Chief Designer of Telos Audio Design, Taiwan at the Munich High End Audio show 2014. I invited him to come to Malaysia to introduce his products, especially the Grounding Noise Reducer (GNR).

Jeff Lin decided to take up my invitation and visited my audio den. He did a presentation of the Telos Audio Design GNR together with some of his other fine products here. He connected the GNR with its dedicated grounding cables (that came with all sort of options from RCA, XLR, HDMI, LAN, USB, Spade and etc, all connected to the ground pin or connection only) to one component at a time and then finally to the rest or remaining of the playing components (the Entreq were disconnected throughout that session).

Upon the first connection to the unused output of the preamp only (Vitus Masterpiece MP-L201 and FM Acoustics 268C), I heard a more profound lower noise floor in the whole presentation. I could almost testify that the noise floor was a tad lower than the whole Entreq set up.

The experiment continued with the GNR connected to the unused output of the source components such as the phono stage (Vitus Masterpiece MP-P201 and then to the FM Acoustics 223) and the Digital to Analogue Converter (DAC-Vitus Masterpiece MP-D201).

The whole act of my audio system improved to a whole new level that I have yet experience. All that were clouded and veiled were suddenly lifted up. The transparency to the source was so much improved as if the glass affixed to the window was removed.

Then Jeff Lin recommended that the GNR be connected to the audio rack and then to the Shunyata V-Ray 2 chassis. I could not believe what I have heard?! What were already a WOW! turned to a double WOW! (WOW!). A few of my audiophile friends and I whom were present in that session with Jeff Lin’s demonstration decided to invest into the GNR and its dedicated grounding cables (of different connectors).

Enter the Star; Telos Audio Design Grounding Noise Reducer (GNR)

A few months later, my audiophile friends and I received our respective GNR and the dedicated ground cables. I connected most of my audio components to the GNR, except the mono amplifiers (Vitus Masterpiece MP-M201) and the loudspeakers (Gryphon Pendragon). Later, Jeff Lin called to inform me of his intention to revisit his new found fans in Malaysia. That time, he suggested to me that I should consider another GNR for my mono amplifier and (the powered bass towers of the Pendragon) loudspeakers. (REALLY?!) I told him that I would not mind to try out that suggestion.

The second GNR was sent to me and I had it connected as per suggested by the designer. At that same time, I received the Tripoint Troy Signature passive grounding for comparison with the Entreq and Telos Audio Design GNRs. I thought to myself then that my audio den had been grounded!

Bring in the Cellist…

Many believed that the piano key was not easily reproduced through an audio system. A lot of the audio system’s set up (fine tuning) must be recognized and optimized to get that piano key sound “just right”. Even a real piano has to be fine tuned from time to time to have it sound right?

I believed the same can be said for the reproduction of a cello through an audio system. I meant the strings of a cello with the realism of the strings backed by its wooden frame. Too often we heard the cello being reproduced ‘bigger than life’ through the audio system, with the mid bass and low bass exaggerated that ultimately muddled up the strings. Here, I would like to play the vinyl album of Antonio Lysy at the Broad, “Music from Argentina” (Yarlung Records 95968-517V).

I admit that I was stunned by the first tone from the cello in that recording through my audio system with the GNRs installed. I meant that each string was clearly played out with the touch of naturalness that was from the wood of the cello chassis. I have heard cello sounded so unreal as if the strings were of metal and the cello’s chassis was of plastic (or worst, of metal). There were no mid bass and low bass boom or exaggeration. Both low frequencies were well articulated, defined and within their intended boundaries.

Thus, the mid mid frequency to the higher frequencies were unperturbed. I could hear a certain touch of refinement (especially) in the higher frequencies. That presented the cello with scale as a whole instead of just where the bow touched the string(s). In addition, the movement of the bow as it cut across the desired strings was clearly heard and felt. I could hear the bow cut from the low to the mid and then to a higher note. To me, that was a testament of the naturalness of tonality (that was clean from the low to the high frequencies).

The accompanying piano…

I have written quite a bit about what I expected in the reproduction of the piano key through an audio system. I have learnt to appreciate that better ever since the inclusion of the GNRs into my audio set up. Imagine that every piano key was presented in its entirety, both frequencies and energy. The differences between a high and low key, and the position of each key in the piano could easily be appreciated. That surreal experience was not just heard but (near) visible (if the recording permits).

The GNRs have cleaned away much unwanted noise in the audio presentation that tended to mess up the mid and lower region of the frequencies. Of course, the higher notes were able to enjoy their intended course. I felt that whenever an audio presentation has too much cloudiness in the mid frequencies, both the low frequencies and high frequencies suffered in term of articulation, direction, definition, separation and etc. In addition, the decay of each piano key played out clearly and accurately. That completed each note from the play.

Here in the same album, both the cellist’s cello and the pianist’s piano were clearly separated in space. Each enjoyed its own certain ‘air and atmosphere’. I could easily close my eyes and appreciate each  musician’s play in that presentation. That brought about the realism of the play, as a whole.

Throw in the human voice into the mix

On the subject of cello playback, I picked my next vinyl album, Rob Wasserman Duets (MCA Records 42131). I love to play the track “Ballad of the Runaway Horse” by Jennifer Warnes, where I found her voice then to be most soulful and recognizable (at the peak of her career).

The problem in that track was the cello tended to overwhelm the mid low frequency. That brought to suffer the separation between the vocalist and the cellist. Here, the GNRs brought that cello under control, and allowed it to enjoy its own space.

I will say this that the GNRs do not change the voice of the vocalist from my audio system. They are just independent grounding units that supposedly reduce the unwanted noise generated by the many audio components and the incoming electrical main. In addition, they are not in the signal chain of the audio system. Maybe I should have this emphasized at the very beginning. But I raised this here for an obvious reason (to me, anyway), knowing how much we care and sensitive of the reproduction of our favourite vocalist through our audio system.

Her artistry was more visible through her control of breath and pronunciation of the words in the lyric. In short, the GNRs allowed another layer of resolution into the presentation. It’s not more analytical, as some would have deduced from this writing, but just more music from the same material source (remember, the GNRs were not in the signal chain).

Rock the Boat!

I brought out my Japanese vinyl pressing of Frankie Goes To Hollywood’s Relax (Polystar 13S-200) and played it loud (100dB+) to rock the boat! At that playback level in most audio system would have been a disaster (to say the least). The whole mix would have been too confused to enjoy as a musical presentation (to me, anyway).

The GNRs maintained the play’s sense and sensibility throughout the (extreme) high volume as if you were hearing it at the right volume level. I believed that it was the tonal balance that brought about the articulation throughout the entire frequencies bandwidth. Here, the mid bass notes and transient were clearly and cleanly defined.

I am grounded (for good)!

After having (almost) every audio component in my system grounded to the independent grounding system from Entreq, Telos Audio Design and Tripoint, I am convinced that it is necessary to have them in any respectable and serious audio set up.

Comparatively, many would have spent so much more in cables, power distributors, tweaks, footers, coasters, and even an audio rack. The result of the addition of any of these branded independent grounding system is obvious enough to justify the additional expenses. I believe that the more revealing the audio system is, the more the benefit from these independent grounding system will be.

Among the three branded grounding system, my preference leaned towards the Telos Audio Design GNR. To me they represent my quest for transparency to the source of my music and at real world price with performance to match against any competitor…enjoy

Audio Ramblings - The TELOS GNR Active Grounding Box

Positive Feedback review site:

By D. Clark

An issue or two back, I wrote enthusiastically about the grounding units from Entreq and how these passive grounding boxes allowed me to hear way more into the music. Yeah, they work as advertised and for sure, they should be seen as a requisite addition to anyone who is serious about audio and their music. Simply better, and at lower volumes, amazingly engagingly good.

And here we have the TELOS GNR Active Grounding Box.

So what we have now is two approaches to grounding: passive, in that the device uses minerals and such to do the trick (Entreq and Tripoint for example) and active with the TELOS unit, actively using a powered circuit. Am thinking the passive option could be seen as being more of a purist approach to grounding in that there it is ‘organic’ and natural, whereas the active option is more… I dunno, an approach that is more complex and potentially more likely to address a wider spectrum of grounding ‘issues’ in that it can target these electronically (at least based on TELOS’ philosophy as noted below). One is wood and the other is aluminum and Plexiglas…. allowing you to marvel at the blinking lights showing you what the active GNR is doing, versus being a storage box for the passive ‘circuit’ in the Entreq. Fancy versus simple?

Oh damn. I used the term magic and no doubt some reader will hit us with these devices being just that… magic and a whole lot of hooey. But then that would be someone who does not listen, has no experience trying any of these units, and bases their opinion on perhaps what they have ‘learned’ from some place in their life. I can accept that… not everything fits perfectly into one’s box of reality.

But back to the task at hand… the TELOS Audio Grounding Noise Reducer. Taken directly from the manufacturer’s Taiwan site, so excuse the grammar and such…

“Grounding facility has always been there for the sole purpose of safety. For example, shock hazard prevention, lightning protection, noise shielding and other functions.

In an audio setup, the effectiveness of the grounding facility has an immediate impact on the background noise. This translates to poor sound quality and greatly worsens the listening experience.

Present Situation

It is almost impossible to get satisfactory grounding facility, let alone one that meets the requirements for audio use. Most of the time, they only adhere to the minimum safety requirements. The common ones have the Neutral wire and the Ground wire connected together, or there is no Ground on the receptacles, leaving the Ground wire unconnected. This allows noise from the home appliances to pollute the Neutral wire, hence, causing interference. Electrical appliances like inverter air conditioner and those with switching power supplies, like computer, generate the highest level of interference.

When the electrical reference point is polluted with noise, it could get into the signal path and you could hear it as noise. The noise could potentially enter the digital circuit and cause bit error.

The Pros and Cons of Passive Audio Grade Grounding Box

Passive grounding boxes out there are made using materials with good conductivity like copper plates, copper rods, copper mesh, mineral powder or some composite substance. The good point about the passive, simulated Ground is that it is very easy to make. In fact, most of them can be made easily.

The challenge is that passive grounding could only alleviate voltage change. They are not able to provide near Ground reference voltage. Hence, it is not able to quickly stabilize the fluctuating potential difference between the audio equipment. This could be liken as ships on the ocean, always floating, the Ground reference is never stable enough.

At the same time, the properties of the minerals or electrolyte will change over time and need to be serviced on a regular basis. This includes material replacement, realignment, or replenishing of the electrolyte before the effectiveness could be restored again.

TELOS GNR Active Grounding Box

Due to the above limitations, TELOS brings new meaning to grounding implementation. And this has been proven to be the most elegant way for any audio setup.

TELOS technical team analyzes audio equipment from a unique perspective. Every audio equipment uses power transformer in order to operate at the correct internal voltage. Hence, each equipment is said to have the primary side and secondary side. The primary side is from the power receptacle, all the way to the input of the transformer. The secondary side is from the output of the transformer to the circuit board. The audio circuitry remains within the secondary side.

TELOS technical team proposes the use of CPU within the GNR to calculate and generate high precision Ground reference voltage. Grounding is achieved by connecting the audio equipment to the binding posts of TELOS GNR that carry the Ground reference voltage. By doing so, GNR is able to truly correct the Ground reference point for the equipment chassis, audio circuitry and the Ground connection.

Using the same analogy as a high precision digital clock, GNR generates low distortion Ground reference voltage, giving each equipment a consistent reference point. When the audio setup is operating on a singular Ground potential, the signal transmission becomes least impeded, avoiding any transmission loss due to polarity mismatch and bit error. Therefore, truly achieving the best transmission possible.

TELOS GNR Active Grounding Box comes with 6 ground cables of the same materials. Thus each equipment is having the same grounding impedance characteristics, this greatly reduces the likelihood of coloration. The purchaser can specify whether they need an RCA, XLR, Spade, etc on the component end of each cable.

By having an isolated Ground for your audio setup, the effect is as good as having a dedicated power line. Through the GNR generated Ground potential serving only your audio setup, noise will be totally isolated.”

Well, that was a mouthful and for sure presents itself as that found on the Entreq site; same issues with the ground, but like I said earlier… different approaches to addressing how to minimize or eliminate the noise and such.

Okay, so the TELOS was supplied with a good number of their “basic” grounding cables: spade to spade and spade to RCA, and after an enquiry… two of their spade to USB. The spade to USB cable is their way better “premium” cable.

TELOS suggests connecting as many components to the GNR as is possible, and when doing so, you can connect a component more than once. They also say not to use more than two cables per post and to keep digital and analog separate—meaning you could use up to 12 cables and even more components (some of the supplied cables have a single spade at one end with double RCAs at the other). They also say one should not connect the TELOS to the AC ground at any outlet nor to connect the unit to the negative terminal on an amplifier.

The TELOS is then connected to everything else via either spade (phono stages), RCA (any RCA for either digital or analog), or USB (like on the NAS and Aries). Okay, way cool. The two units, while being of way different approaches, actually play really well together and as such can be used together, though for different applications as noted.

And, what do I hear one might inquire. Music… and I mean way more music with the TELOS in place than without the TELOS. Differences with the TELOS are rather instant in that the TELOS needs little time to do what it does. Simply unplug the AC cord powering the unit (there is no on/off switch) and, bam… there it is… of which I used the stock cord and then swapped in a better cord from Pangaea and for sure, things did improve… so am figuring that even a better BETTER cord could make it even better still. Anyhow, even with the stock cord, I can hear farther into the depths of what is on the file, disc, or LP. The results remind me (aural memory) of what I experienced with the Entreq. Now again, I am not comparing them… but geesh, if I read what I wrote about the two Entreq units connected to everything I could toss their way… the similarities are spot on. Sort of like a Venn diagram where 98% of the two circles overlap as opposed to just a wee bit on either side. Stunningly solid in every way I can think of…

And no, as I said about the Entreq, a grounding unit is not going to change the sound in terms of some sonic tapestry (that is making the sound warmer, leaner, whatever), but it will change the sound in terms of resolution, space, decay, presence… and so on. By reducing or eliminating noise that is riding along with the signal—of which is not audible or something that one can point a finger at—there is less in the way of what you want to hear… your music. You will hear more texture and space around the notes, images will become locked in and just right there… everything has its own place and presence. Less confusion and more order to the music. You will hear what is there, whether it is good or bad… meaning bad recordings will still be bad though you will hear more of what is there… and oh so natural. Meaning for sure there is less edginess to the music being easier on the ears with less strain and grain.

I absolutely love what the combo of the Entreq Poseidon and TELOS GNR are doing to the music here in our system. This is such a stellar combo: the best of passive working on this and that with the best of active handling all the rest with such ease… musical as all get out that I am way WAY happy. You must audition these units. I mean this with all my heart…

But where to start? Well, either one works pretty much anywhere, though the Entreq will address two grounding issues that the TELOS does not: amplifier terminals and AC outlet grounding. On the one hand, perhaps they feel that these are less important or are of something that should not be dealt with. On the other hand, the TELOS is active and based on what TELOS says on their site, should be more universal and effective in terms of dealing with the noise and such on the ground. No doubt they will offer an audible difference—but here the differences are too difficult to put to pen. Sorry, but substituting one for the other takes too long (cables, cables, and cables), there are noted uses that differ for each, the requisite time needed for them to settle in and do what they do is vastly different… so not going to happen. What I am hearing is the two working together. For sure I did try just the TELOS connected to what it could connect to, minus the Entreq and yeah… it works. You get it all as I had said above… and in spades. Adding the Entreq, as noted above, certainly takes things further along… I got more than just what the TELOS presented solo. Makes sense as the Entreq was now dealing with places the TELOS could not by design. Get one, get both… you won’t be disappointed.

Quibbles? None that come to mind. The unit works, is dead quiet, it does put on a light show so people will ooh and aah as to what is going on, but they will also ooh and aah about what they are hearing too. Again, grounding units are not sonic band-aids but should seriously be considered by anyone who has their system at its pinnacle.

The best recommendation I can offer is that a well-known audio importer of several highly respected products was listening to my system a few weeks ago… he visits often so he knows my system quite well. After a few songs he asked me what here in the system is different since the last time. I mentioned the TELOS and Entreq along with a few cables that were in the system for review (PAD interconnects, Triode Wire AC cords, and Skogrand speaker cables). He  looked at me and said, “If you don’t own the stuff… buy it. This is the best ever.” Highly recommended.

White paper: The concept of GNR

Grounding Noise Reducer (GNR) – Active Grounding Unit

Design and manufacture: Telos-audio


Under normal circumstances, close to 100% of electrical signal transmission from transmitter to receiver can be achieved with good matching impedance.

When the zero potential of both the transmitter and receiver starts drifting; under circumstances such as long distance transmission or high input impedance. Even with good matching impedance, error will still be present when a signal is received due to instability of the zero potential.

For analogue signals, it causes a lack of fidelity of different levels and affecting both audio and visual signal’s realism. In the case for digital signals, this instability will cause time base error such as jitter and during worst case scenarios it will cause bit loss.

Traditionally, within audio and A/V systems, very large cores of grounding conductors can be used to reduce the impedance, or the use of star connection grounding, to create an equal zero potential. However, different devices within the system normally rely on signal cables to get connected – with different impedances, so conductors have limitations and is difficult to achieve a perfect star connection Concept. So the GNR product was developed to remove the problem.

HiFi White paper image

The GNR creative solution is based on a systematic concept, the development of a new original approach. The picture below illustrates the GNR concept of grounding between devices; connection of all devices to the GNR via low impedance cables based on star topology architecture. The GNR then provides equi-potential to all devices connected and filters noise. A ‘catharsis’ channel is also created to allow these consolidated residual noises to be removed.

Telos Audio White Paper

The GNR provides multiple points for connection to devices. Every signal or chassis earth point has an independent noise filtering module which will first convert noise from each connected device into heat to be dissipated.

The noise filtering module consists of capacitors, resistors, inductors and components which generate eddy current. After this filtering process, the grounding ‘signal’s are channelled to the Centralized Switching Control Unit. This process will prevent noise from devices cross contaminating and will allow each device to have similar zero grounding potential.

The Environmental Potential Generation Circuit is dependent on the device’s environment and together with the “Live” and “Neutral” phase of the power supply mains, a potential difference will then be generated. The analogue digital sampling circuit (ADC) changes this potential difference into a digital signal which is then mathematically processed by a microprocessor. The microprocessor will then determine the power supply mains; the “Live” and “Neutral” phase before activating the Centralized Switching Control Unit to implement the correct change, allowing the unified devices zero potential to be connected to the power supply mains grounding potential again for an absolute reference zero potential.

This will result in system’s absolute stability and low noise zero grounding potential. This is effective in preventing grounding error; which causes signals interference and loss of fidelity.

Paper prepared by: D. Han, attachment to his ‘Mono and Stereo’ Review.