As audiophiles, we are always on the lookout for new products that advance the state of audio reproduction. Recognizing that few of us can justify ultra-expensive products, no matter how amazing, we try to concentrate on more the affordable options. In 2022, we looked at the Equipment Vibration Protectorsfrom AV RoomService, Ltd., the LSA HyperDrive2 Hybrid Stereo preamplifier/headphone amp, Cables from Audience, the TB-10D Class D Amplifier from Fosi Audio, the FiiO Jade KA1 DAC/Headphone Amplifier.
Equipment Vibration Protectors from AV RoomService, Ltd.
To paraphrase the Beach Boys, vibration is good. Without it, we’d have no music, no sound, nothing, just the murderous emptiness of space. But the same vibration that transforms the wood of a guitar, violin, or drum into a beautifully resonating surface can also lead to problems with your audio gear. It’s interesting, because in past decades, metal “spikes” for speakers have been touted as a way to securely anchor your speakers to the floor. But is that a good thing? Wouldn’t that just turn your floors into additional resonators?
The answer is yes, you should decouple your speakers, and other gear from its surroundings, not intentionally couple them. Over the years we’ve seen very sophisticated, very expensive attempts to decouple gear from vibrations. Sometimes that is accomplished with simple DIY solutions, such as a sheet of rubber or cork to dampen resonances, or engineered designs that employ metal, machine work, various types of rubber or other elastomers. Some might argue about the claims made for different cables, but acoustic isolators are a different case study, since they rely on simple physics, and many of them can actually be measured.
Several years ago we first met Norman Varney, a cheerful man, who was demonstrating a different kind of acoustic isolator made from specialized fiberglass, topped by different materials and in different sizes, depending on the use. Norman was kind enough to supply us with some products sized approximately for speakers and audio gear. You can select from different sizes to fit your gear, but you may also choose from different densities, and AV Room Service provides a calculator to determine the proper product for the weight of the speakers or components.
Another thing we love is the utter simplicity of the design of the Equipment Vibration Protectors, which belies the complexity of the product. For example, Varney was very clear that we weren’t to “slide” the units into place, because they could shear and become damaged. The equipment must be set straight down on the EVPs. Do they work? Yes. With our reference Emotiva T2+ speakers, in our highly sprung hardwood floors over a basement, the amount of vibration was easily detectable when we stood on the floor with bare feet. Switching to EVPs under the T2+ made the floor stop vibrating. Audio-wise, we felt the lower bass was less muddy, more easy to discern differences between notes. The same change was heard in the mid-tones. Overall there was a lack of reverberation.
We heard the same when EVPs were used at Capitol AudioFest, and THE Show. In one particular showroom where we spent time before and after, the effects were easily audible. Best of all, they are priced lower than most so called “Audiophile Grade” acoustic isolators. Our suggestion is to start with your speakers, then move on to your turntable. Our reference Luxman PD-572 showed a dramatic difference. Before the EVPs, our cabinet was incredibly sensitive to even the slightest touch, after the EVPs, we actually tap or knock the cabinet without problems. We did find that we needed to screw the turntable’s leveling pads all the way up, tight against the base of the table. When we had them extended, the fulcrum point shifted so that the turntable was too loose. Once retracted and placed on the EVPs, there was a marked improvement. Once again, the improvement came in the bass response, with less feedback-induced reverberation. We heartily recommend Equipment Vibration Protectors from AV RoomService, Ltd.
For more information on the Equipment Vibration Protectors from AV RoomService, Ltd. visit: https://avroomservice.com/evp-2/
LSA HyperDrive2 Hybrid Stereo preamplifier/headphone amp from Underwood Hifi
At Mac Edition Radio we love quirky, passionate, off-the-mainstream ventures, and Underwood HiFi seems to meet that description head on. Founded and guided by Walter “Wally” Liederman. Wally is a 50-year industry veteran, with a variety of roles in retail, as a buyer, and as a consultant. Finally, he arrived at his side hustle, the home-based business Underwood Hifi through which he marketed new products, closeouts, B-stock, discontinued products and other specialty audio items that many manufacturers didn't want to promote through their established distribution chains.
When audio marketing legend Bill Leeban asked if we were interested in reviewing a new headphone amplifier from LSA (Living Sounds Audio), we jumped at the opportunity. Two days later a box arrived containing the LSA HyperDrive2 Hybrid Stereo preamplifier/headphone amp. It’s a solid unit, with two E88CC tubes sticking out of the top. There isn’t any protection for the tubes, so best to be very careful around the topside. The unit is black and silver in color, and has a solid feel with lovely graphics, and easy-to-use controls and features. The company description details its features. Normally, we wouldn't just list the specs, but their description is void of any exaggeration, so we’ll just reprint it here.
“The LSA HD-2 Preamp/headphone amplifier is a hybrid tube preamplifier combined with a solid-state headphone amplifier that provides up to 2W of power into 32ohm headphones. It has state of the art microprocessor controlled operation for graceful warmup of the tube circuitry, pop-free startup and shutdown, gain select, output mute, and the pushbutton switching between three RCA audio inputs. It features two sets of audio outputs to drive an amp and even a subwoofer or two.
A solid state relay (SRR) is used to provide DC output protection for your sensitive headphones and adds no distortion to the signal and will never wear out, unlike a mechanical relay.
The input stage utilizes a pair of E88CC tubes operating in the ultra-linear range as a Class A cathode follower buffer with a tube-based constant current source (CCS) to provide a natural sounding preamp to drive the solid state headphone stage.
The output driver stage of the HyperDrive2 utilizes the class-leading TPA6120A2 monolithic headphone power amplifier from Texas Instruments to cleanly and solidly drive almost any headphone. This buffer/driver topology gives the HyperDrive-2 headphone amplifier a clear and non-fatiguing SE Class A harmonic profile, while maintaining a low level of total harmonic distortion in the 0.005% range at average to loud volumes with most headphones.
Three gain settings (0/6/12dB) are selectable from a toggle switch on the front panel to allow the HyperDrive-2 to be matched to any source or headphone with the proper signal levels. The preamp outputs use the best-in-class Texas Instruments OPA1656 op-amps to provide a clear and musically dynamic output when used as a stereo preamplifier.
The power electronics are provided by a custom-designed DC-DC switching circuitry for the 90v B+ voltage and 6.3v filament voltage. A high-quality and convenient universal input 60w desktop style external power supply provides the power for the HyperDrive-2. The output impedance of the HyperDrive-2 headphone amplifier is 13 ohms.
Volume control is provided by smooth turning Alps pot and all op amps utilized are class leading TI OPA1656/1642 for the best combination of transparent sound and musicality. A simple toggle switch selects between three different gain settings of 0dB/6dB/12dB through a relay There is also a convenient push button microprocessor controlled mute function effected through use of low distortion solid state relays (SSR) which are also used for DC output protection to prevent damage to headphones resulting from an output stage or power supply anomaly.
The HyperDrive2 is capable of driving 2w into 32ohms, thus capable of being paired with the most demanding low-sensitivity headphones. The SET tube buffer provides for a beautiful SE Class A harmonic profile that is second harmonic dominant with monotonically descending higher orders with an overall THD of 0.002% at 500mW into 32ohms. A handsome and heavy CNC machined aluminum chassis with a velvety and durable powder-coated finish that expresses the amplifier’s sense of speed and power, yet with a reserved elegance.”
Our first unit worked perfectly for about a week, when it developed a clicking sound that caused the tubes to turn off and on. One email and a day later (seriously, what service!), a replacement unit was on hand, complete with a return shipping label. I did some tests and discovered that the Audience forte V8 Power conditioner with their PowerChord power cable as the supply for the external power supply provided with the HyperDrive 2 provided a slightly lower noise floor, and a bit more smoothness. This was subtle, as the HyperDrive2 had no audible faults that we could find.
Our biggest challenge was figuring out how to feed it, as most of the DACs we currently have already incorporate superb amplifiers. I tested it with the superb Oppo HA-1 Headphone Amp/DAC, and the excellent EarMen TR-Amp which has an analog switch for Direct DAC or PreAmp function, we used the Direct option, so as to only judge the HyperDrive2. The tubes that make up the input section, imparted a bit of warmth, not overtly, but with a less sterile sound as provided by the TR-Amp with its headphone amp. It was truly silent – no noise from the volume control, no clicks or pops, just a silent backdrop.
Using a variety of headphones, including the HIFIMAN Sundara (Open Back) Planar Magnetic Headphones, that we found ourselves setting the gain control to its highest setting, while using the Audeze LCD-1 allowed us to use the middle gain setting. Either way, we felt that the amp could handle just about anything we threw at it, including some Etymotic ER4XR Earphones. Those particular IEMs are very revealing, and the HyperDrive2 passed our listening tests with flying colors. Having three options for inputs provided enough flexibility for most uses, allowing a CD/DVD/Blu-ray deck, a DAC, and another component, possibly a turntable, if you included the LSA .5 Phono Stage.
We are looking forward to testing our Luxman PD-572 turntable equipped with a Dynavector Ruby Moving Coil Cartridge in a future review with the .5 Phono Stage, and possibly their Discovery Warp 1 Amplifier. If you haven’t heard of LSA before, certainly the awards they’ve garnered for their VT-70 Integrated tube amplifier should pique your interest. All reflect a commitment to affordable audio, in the spirit of Hafler and others.
We were excited to try the HyperDrive2. Everything about it, was well, just fun. It has a great solid design, first-rate fit and finish, laudable sonics, and enough power and flexibility to drive just about any headphone or IEM you can think of. I found myself listening to all sorts of content, music, high-res audio, videos, and found it a joy to use. One thing to learn from working with headphone amplifiers is that they sometimes becoming fatiguing. Not so the HyperDrive2, using it was like a tonic at the end of a long day. Highly recommended.
For more information on the LSA HyperDrive2 Hybrid Stereo preamplifier/headphone visit: https://www.underwoodhifi.com/products/lsa-headphone-amps
Audience forte V8 Power conditioner with their PowerChord power cable, and OHNO Analog Audio Cables
I met John McDonald, owner of Audience at THE Show in Long Beach a couple of years ago, and apart from being an affable guy, he was also very patient as I peppered him with a multitude of questions about cables. I don’t understand all the science involved with cables, but the more I’m around folks like McDonald, the more I’m reminded of how much I don’t know. My experience with cables dates back to the first Monster Cables, sold to me by Noel Lee himself. I went back to my apartment in college, and along with my friends, did A/B comparisons with lamp cord of different diameters, and finally the Monster Cable. And… we all felt we could hear a difference. A few years later, I upgraded my turntable to Vampire Cables, and pretty much left it at that.
Then came my entry into the world of High-Res audio where suddenly I could really start to hear the differences between gear, including cables. It was also the first time I’d heard of OHNO copper, courtesy Jason Liao of Oppo Audio, whose new line of planar magnetic headphones came with OHNO cables. Curious what made this copper so special, I researched it, talked to a metallurgist friend, and started to understand what OHNO Continuous Casting meant, and Dr. Atsumi Ohno at the Chiba Institute of Technology in Japan’s role in creating it. The bottom line is that OHNO copper is seriously pure stuff, and ideal for no-compromise audio reproduction. And McDonald’s Audience OHNO line uses it to good advantage.
Audience has a full line of cables and conditioners. Since I’m not working with ultra-high end gear, McDonald suggested I try out their entry-level OHNO cable lines, which suited me just fine. The products included their Ohno RCA to RCA cables, OHNO Stereo Mini to RCA, PowerChord AC line cables, and the forte V8 Power conditioner. All were beautifully made, from the red metal case of the forte V8 Power conditioner, to the XLPE (cross linked polyethylene) insulation. The forte f3 powerChord AC cords are both flexible and feature cryogenically treated brass contacts. All are competitively priced with other high-fidelity cables; in fact they are often lower priced.
How did they sound? The interconnects were extraordinarily resistant to hum or other radio interference. When I was testing the LSA HyperDrive2, I switched from some competent cables to the Audience OHNO cables and found a quieter noise floor. The shielding worked, as the cables had to navigate a slew of other digital gear, from RAIDs, to hard drives, and power supplies for a myriad of devices, yet the Audience cables were absolutely silent. As for the audio, there was an enhanced mid-range, with vocals and instruments having a more forward sound, discernible even to a skeptic like me. This was apparent on the newly restored and released stereo mix of The Beatle’s Revolver, one of this year’s most important releases. Listening to Eleanor Rigby, through the EarMan TR-Amp, and the LSA HyperDrive2, was a revelation.
All of our audio equipment took advantage of the forte V8’s eight AC sockets, as well as of the advanced filtering it offers. Once again, in a house filled with digital imaging and audio gear, there wasn’t a hint of line noise. I asked a number of colleagues about the impact of the latest generation of power conditioners, on things like external power supplies, and the consensus was that it should help, but the variables are such that you can’t reliably predict the outcome. I wrote last year that one of the conundrums about cables is that measurements don’t seem to be the story.
In fact, most cables have almost identical measurements, which provides the ammunition for the anti-cable crowd. Reliable audiophiles will tell you to just sit and listen, and if you can hear the difference, great. If not, that’s OK too. In my tests, I can say that the cables did make a difference, most audibly with the analog interconnects. I’m still sorting out my response to power conditioning.
I did a number of tests with the Audience powerChord power cables, to discern a difference. In the end, I concluded there was a difference, an improvement in the hard to describe “air” in the room, but that the result varied on the equipment being used. For example, with my Oppo UDP-205 4K Ultra HD Audiophile Blu-ray Disc Player, the power cables didn’t have as much impact they did on amplifiers and pre-amps, which sounded quieter with the conditioners. Of course the UDP-205 is widely heralded to be one of the best players of its sort ever made, and they paid an enormous amount of attention to the power supply. For my older pre-amp and amplifier, I had to use the original OEM hard-wired power cords into the Audience forte V8, which did seem to help tame the noise floor. In the future, I’ll be looking into the possibility of retrofitting the supplied power cords with sockets so as to enable the use of the powerChord series directly.
I’ve long thought that the rancor over power cables could be defused if they were simply called something more descriptive like AC Power Conditioner Cords, or AC Power Conditioner Components, since they are more than just a way to transfer power from the wall to the component. They often consist of unique materials, with proprietary winding and insulation technology, so just calling them power cables does them an injustice. Either way, we think the Audience line of OHNO analog interconnects, forte v8 power conditioners, and forte f3 powerChords are an excellent and affordable entry into the world of high quality cabling. They come highly recommended.
For more information on the line of Audience cable and power products visit: https://audience-av.com/cables/
Fosi Audio TB10D Class D Audio Amplifier
By now, everyone has become aware of the hot new area for audiophile exploration, namely inexpensive high fidelity products from China, nicknamed Chi-Fi. For some, it’s the most fun you can have for a few bucks. For others it’s proof that solid audio can be ridiculously affordable, and then there are those few who, well, just don’t take it seriously. But, on that last point, the doubters should reconsider.
I’d heard colleagues talk about Fosi, especially after Randy "The Cheap Audio Man", shredded one of their amps, only to have the company tweak, re-engineer the amp, and then resubmit for review. Randy's conclusion that the revised amp was that it was a serious contender. What’s interesting about this influx of products is that not only do they sport a wide variety of features, they are using absolutely current chipsets and parts that strike me and others as astonishing at the price. The Fosi TB10D is rated at 300 watts per channel, yet is about the size of a paperback book. It’s a simple unit, with an on/off switch, volume control, bass and treble controls, and a set of RCA inputs, and speaker outputs. That’s all folks! It ships in a box that is just a bit smaller than a shoebox. Is it 300 watts? I don’t think so, and it varies with the power supply, but can it drive a relatively inefficient speaker to thunderous levels? Yes… with ease.
The supplied power supply is 32 Volts 5 Watts, and you can order beefier models. During my testing with recently released book and SACD soundtrack to “The Loudspeaker” by Paul McGowan of PS Audio fame, I discovered the limits of the amplifier, when I triggered the protection circuit numerous times. I was listening to the final tracks on the album, which really push an amplifier in addition to being great music! Two tracks that I loved listening to were by Thom LaFond, and the Briana Harris Quintet. Both tracks are superbly performed and recorded and really let the listener know what your amplifier and speaker can deliver. I played them loud enough that it was the at the level of a club just a table or so away from the band. Of note are the drums in the Briana Harris Quintet, where you can really hear and feel the drums.
The Fosi TB10D reproduced the kick drums with all the punch and depth you’d expect of a much more expensive amplifier, revealing just how good the TPA3255 chip can be in the right topology. It was on those drum beats that I kicked off the protection circuit for a second or so. There wasn’t any distortion, the sound just cut out. To be fair, it was loud, really loud, but I wonder if the problem is the power supply, and Fosi promised to send out a higher capacity one as soon as they were back in stock. I’ll update this review once I have a chance to compare.
I utilized Audience OHNO RCA connections from my Oppo UDP-205 4K Ultra HD Audiophile Blu-ray Disc Player, and again Audience OHNO RCA between my GAS Thalia Preamp to the Fosi TB10D amplifier. After the holidays, I’ll test the system again, using the new Fosi X3 tube preamp, to see how it stacks up. Keep in mind that the Fosi TB10D amplifier was selling for roughly $70, which just plain blows me away.
There are a few things I’d love to see tweaked in the future, which are a detent on the tone controls to signify neutral or, better yet, a switch to remove the tone controls from the audio circuit. I’d also love to see an LED indicating safe operation, or a “Danger Will Robinson!” if you are pushing the unit too hard. There have been reported quality control issues with some inexpensive Chinese audio gear, but our sample TB10D, has been rock solid, no hint of problems at all, even after long periods of heavy use.
It’s kind of funny to have to figure out a way that our heavy AudioQuest speaker cables can connect to the amp without pulling it off the rack, since the unit is so light and small. Interestingly, no matter how hard, or long I pushed the amp, it never felt more than lukewarm to the touch, and the same went for the power supply.
We love this little amp. It sounds musical without sounding harsh or grainy. It can handle difficult loads with aplomb, and it’s crazy affordable, with solid build quality. Matched with the right speaker, you might just fall in love with it as well. The Fosi TB10D Class D Amplifier comes highly recommended!
For more information on the The Fosi TB10D Class D Amplifier visit: https://www.fosiaudio.com/product/2-channel-amplifier/tb10d/
FiiO Jade KA1 DAC/Headphone Amplifier
We love bargains, and audio bargains are no different. FiiO is a well-known name in audio due to their affordable gear, with rich feature sets, and excellent build quality. We’ve reviewed a number of products from them, and I was jazzed to hear about the new FiiO Jade Audio KA1 DAC/Headphone Amplifier, which might be among the best buys in audio.
Sporting the ES9281AC PRO DAC chipset, it is probably the lowest-cost unit that support MQA rendering, support for iOS, Android, Mac and Windows. It can handle 32bit/384kHz, and DSD 256. You need to choose your model, either USB Type-C or the Apple Lightning connector. One feature we like is the color-coded RGB Status Indicator: Blue: 48kHz or lower sampling rate, Yellow: Greater than 48kHz sampling rate, Green: DSD tracks, and Magenta: MQA rendering.
It kind of drives us nuts not to know what is actually going on with a DAC. I want to know the sampling rate and bit depth, if for no other reason to confirm that what is leaving my music software is properly reaching the DAC. Amazingly, we didn’t expect all this at what has to be audio’s best price. Believe it or not, KA1 sells for just about $50.
The one area in which it falls a bit short is power. Its output power is rated at 45mW, which is fine for most earphone and IEMs, and we found it worked well with our test headphones, including our Audeze LCD-1 Planar Magnetic headphones. So, how did it sound? Great! Open, airy, with good soundstage, it was free from distortion at normal listening levels. For bass-heavy content we sensed a bit of reserve, but with some efficient headphones, it works great.
We also tested it with our Android phones, and a few different Apple MacBook Pros and iPads. All worked fine with the KA1; no need for drivers, no compatibility problems, just plug and play.What’s surprising is how close it is in performance to much more expensive USB DACs that can be double or triple the price. Physically, it’s a small device, with a braided cord attached to a small metal case with the headphone jack and electronics inside. Jade Audio is a budget offshoot of FiiO, and we can confidentially say that for music lovers, the new, incredibly affordable and feature rich FiiO Jade KA1 DAC/Headphone Amplifier should be on your gift list.
For more information on the FiiO Jade KA1 DAC/Headphone Amplifier visit: https://fiio.com/ka1
Harris Fogel with Nancy Burlan and Frank Schramm, Posted 12/8/2022