Headphones: Less Than Ideal Hi-Fi Gear?

Even though it was deemed an indispensible component when the Sony Walkman became king back in the 1980s, are headphones, until now, has always been a less than ideal way to listen to music?

By: Ringo Bones

Dubbed by conservatives as the most antisocial way to listen to music back when Sony’s Walkman was new, the shortcomings of the ubiquitous headphones has recently been brought back into the spotlight after the shortcomings of a flagship Apple product – i.e. the Apple AirPods wireless headphones and their Mainland Chinese made knockoffs – as early users complained of excessive background hiss, not to mention early users old enough to remember 1980s era cassette tapes saying that the hiss levels are worse than that of dubbing a copy of a copy of a prerecorded cassette tape album. But are headphones really the weakest link of all the sound producing transducers in our high fidelity audio hobby?

Despite its shortcomings, audio enthusiasts old enough to have taken sound quality seriously back in the 1980s had surprisingly managed to make due of listening to music via headphones. Weird between-the-ears stereo soundstage when listening to plain vanilla 2-channel stereo cassette recordings and producing more background hiss in comparison to conventional loudspeakers notwithstanding. But let us explore more on the headphone’s hiss issue given that, especially when listening to prerecorded cassette tape albums as your primary music source, is already inherently hissy in the first place.

Hiss is more noticeable through headphones than speakers for several reasons. Since headphones lie closer to the ears of the listener in comparison to loudspeakers, any hiss that the headphones’ produce is readily transferred to the eardrums. Headphones are more sensitive than loudspeakers – i.e. headphone sensitivity are typically measured in decibels per milliwatt as opposed to decibels per watt when measuring loudspeaker sensitivity – so headphones are more likely to pick-up the faint residual hiss produced by your audio rig, like that in the preamplifier stage. And headphone models that isolate your ears from outside sounds can also prevent such sounds from masking hiss, denying the user from using Mother Nature’s naturally generated dither noise.

Linaeum Tweeters: Exotic Tweeter For The Masses?

Often described as the lowest cost alternative for budget conscious audiophiles disenfranchised with the dome-tweeter sound, is the Linaeum Tweeter a true-blue “exotic tweeter” for the masses?

By: Ringo Bones

When RadioShack collaborated with Mystical Audio Limited to release their Optimus PRO series of hi-fi loudspeakers back in the mid-1990s, it was hailed by audio experts and reviewers as the “best sounding loudspeakers they have ever heard in the $300 to $500 price range”. While actual audiophiles who can’t afford ribbon-tweeter and planar-magnetic tweeter equipped exotica in the four-figure to five-figure price range had hailed the RadioShack Optimus PRO series as a veritable godsend at the time. I mean hearing what an actual 1990s era grunge guitar band produced in a budget-conscious audiophile’s listening room after concluding budget dome-tweeters seem to just don’t cut it sonic wise can be a revelation back then.

Sadly, the bass and lower midrange sound quality of the RadioShack Optimus PRO series was sonically below par in a side-by-side comparison to their old-fashioned dome-tweeter equipped competition in the $250 to $1,000 price-range. Not to mention that the inherent nature of the Linaeum Tweeter design will produce a harsh high frequency sound quality if operated below 3,000-Hz in the audio spectrum. But what makes the Linaeum Tweeter a value-for-money alternative to the good old-fashioned dome-tweeter in the entry-level hi-fi loudspeaker market?

What’s so special about the Linaeum Tweeter? In a conventional tweeter, a coil of wire is suspended between the circular poles of a ring-shaped magnet that moves a cone or a dome-shaped diaphragm backwards and forwards according to the dictates of the electrical signal, allowing it to produce audible sound from the power amplifier’s electrical signal. In the Linaeum Tweeter, there is still a voice coil, but this time it is flattened into a vertical shape and suspended between opposed rectangular magnetic poles. The voice coil still moves backwards and forwards, but instead of driving a cone or dome-shaped diaphragm, it pushes and pulls the vertical joining point of two semi-cylindrical 3-inch long sheets of stiff plastic film, each of which is fixed at its own end. Imagine two empty beer cans side-by-side, the point where they touch is where the voice coil is attached. Under the influence of the electrical signal from the power amplifier, the two semi-cylinders rotate back and forth, the resultant traveling waves producing sound.

The advantages of the Linaeum Tweeter design over a conventional cone and dome-shaped tweeter design are a uniformly wide horizontal dispersion pattern of the produced sound and good linearity, both of which lend the Linaeum Tweeter some of the attributes of a good, but far more expensive, planar drive unit. If as in the RadioShack Optimus PRO LX series, two sets of diaphragms are placed back-to-back with a common magnet structure, sharing a common voice coil, those at the rear pull when the front one’s push. The resulting sound radiation to the rear should  produce an enhanced feeling of “airiness” to the loudspeaker’s sound in all but the most “acoustically dead” –I .e. unreflective – of listening rooms.

The Linaeum Tweeter further gained its reputation as the “exotic tweeter for the masses” after RadioShack decides to discontinue the Optimus PRO LX series and sold them heavily discounted – including the after-market replacement Linaeum tweeters – around after 9/11. Some RadioShack outlets had even sold the Linaeum Tweeter as low as $15 per pair further on. Now virtually impossible to find outside of heavily inflated priced working ones offered on e-bay, adventurous hi-fi enthusiasts had managed to experiment with them during the first two decades of the 21^st Century. If operated above 3,000-Hz, Linaeum Tweeters offer more natural and realistic sounding high frequencies that dome tweeters in the $100 to $500 price range. When operated at 6,000-Hz or higher as a super-tweeter, the Linaeum Tweeter can easily make a DIY loudspeaker sound as if it is 10 to 20 times the price of its actual purchase price.

What Does a 1990s Era Hi-Fi Sound Like?

Did 1990s era hi-fi sounded like it should because hi-fi enthusiasts finally wanted to hear more of the music – instead of the audio gear?

By: Ringo Bones

Why did 1990s era high fidelity audio managed to cast such a long shadow that every well-reviewed audio gear are now commanding serious second-hand prices? Well, if you’re like me who got started to appreciate hi-fi audio as a hobby during the mid 1980s but only managed to acquire the disposable income needed to buy a much coveted kit during the early 1990s, it is safe to say that almost – if not all – well reviewed budget hi-fi gear, especially speakers, that entered the market between 2010 to 2019 is not that much different, sound wise, from their budget counterparts of the 1990s.

Maybe it is because 1990s era hi-fi enthusiasts finally decided to hear more of the music – instead of the hi-fi gear – that tonal neutrality and timbral accuracy finally managed to trickle down to budget hi-fi gear back then. Remember during the mid 1980s budget amplifiers, and signal sources – CD players, tape decks and turntables – were inherently designed to drive an inherently colored loudspeaker, that only a handful of 1980s era hi-fi gear are cherished compared to their rivals made a decade later.

During the latter half of the 1990s, even a relatively colored-sounding loudspeaker – like the Cabasse Farella 400 – especially the early model ones with an unmodified crossover network and driven with an entry-level Rotel RA-920AX integrated amp can manage to sound way more neutral and musically realistic when compared to an original JBL 4312 loudspeaker driven by an integrated amp manufactured In the mid 1980s. I mean to my ears at least – the Cabasse Farella 400 managed to produce a more realistic sounding acoustic guitar sound from a recording on a redbook spec CD than the late 1970s era JBL.

How Many Subwoofers Do You Actually Need?

Even though you could get away with just one, how many subwoofers do you actually need to achieve natural sound at a reasonable cost?

By: Ringo Bones

Believe it or not, subwoofers were already sold by hi-fi retail stores around the mid 1970s. Sadly, those early subwoofers were very notorious for sounding as if an electric bass guitar connected to a loud bass guitar amp is playing along with the music in your listening room – even when playing small-scale chamber music. After the early design excesses were weaned out, subwoofer in the home has undergone a hiatus that made it desirable again in a few years time.

The subwoofer gained popularity again in the 1980s due to a great number of affordable small loudspeaker systems designed with very small woofers / main drivers – i.e. 5 to 7 inches or so and, sadly, most pain-in-the-ass interior decorators find them attractive. Sadder still, the growing impracticality for many hi-fi enthusiasts to own loudspeaker systems with 12-inch or 15-inch or larger main drivers for reasons of cost, space or room aesthetics (thanks to your pain-in-the-ass interior decorator) finally made subwoofers a viable option when it comes to system building.

During the early 1990s, a partial, but interesting solution to the problem was the introduction of the three-piece system. This generally consists of two quite small loudspeakers that cover the frequency range down to 100-Hz or so. Such a loudspeaker system with a 5-inch or 6-inch main driver are fairly easy an inexpensive to design and manufacture. But a loudspeaker system with the bottom two octaves missing is not very satisfying to the seasoned audiophile, so a third component is added – the subwoofer.

The rational of using a subwoofer is that the main front left and front right loudspeakers can be designed to give appreciable power output and have optimal performance at very low frequencies because the two main left and right front loudspeakers no longer has to reproduce the very low frequencies. And while the subwoofer no longer has to reproduce the higher frequencies assigned to the front left and right loudspeakers, that one subwoofer box can now – in theory – be placed in a more or less out-of-the-way location in the room since the low frequencies – i.e. below 100-Hz – have very little directionality. It was generally thought – since the mid 1960s – that a single monaural channel for frequencies below 100-Hz was needed and also because frequencies below 80-Hz were, allegedly, mixed to monaural anyway. This latter factor was a result of the limitations – and still is - of the mechanical reproduction process used in making vinyl records and back then, open-reel tapes are a way, way more expensive alternative to vinyl playback. But when properly connected, two subwoofers operating in stereo absolutely sounds more gorgeous that a system with just one, even in casual listening.

The assumptions that justified using a single subwoofer has some basis in fact because three piece systems have been, and are still popular when space and room styling (thanks pain-in-the-ass interior decorator) take precedence over other acoustic considerations. Audiophiles who preferably listen to rock music usually place the subwoofer to the left because the bass guitarist is usually mixed to the left of the soundstage, while those who listen to large scale Classical music place the subwoofer to the right because in a majority of orchestral recordings, the low frequency instruments tend to sound as if they are located on the right of the soundstage. However, over the years, I have some concerns and reservations about the technical justifications for the three-piece system.

It can also be quite a shocker to know that not all, or even most, loudspeaker setup absolutely needs a subwoofer or two to make them complete in the low bass. To my ears, it might be the wisest decision to get a truly full-range loudspeaker in the first place, since it will have been designed as a unit and have a smoothly balanced response over its full range. However, in the case of smaller bookshelf-type loudspeakers, considerable advantage can be had by removing the lower two octaves of the sound from the two main left and right loudspeakers and diverting them into a good subwoofer. The advantages are that the subwoofer now handles the hard-to reproduce very low frequencies due to much higher power requirements freeing the smaller loudspeakers from the greater power and displacement demands of reproducing the very low frequencies. This can result in lower distortion in the small loudspeakers and considerably improved sound quality from them. It also allows planning for system growth – that is if you first invest in a good, small pair of loudspeakers, you can augment them later by increasing bass capacity with a subwoofer.

But the question now is whether one, two or perhaps more, subwoofers should be added. If only one subwoofer is added, the result would be a three-piece system with monaural bass response below 80 or 100-Hz. If two subwoofers are added, the result is the two bookshelf-sized loudspeakers virtually becoming two full range loudspeaker system with a full stereo low bass capability. But does it matter if we have stereo or monaural low bass? To my ears and my over 30 years experience in being an audiophile, I believe that it does for at least two reasons. The first is that we have a much better program material today from the Redbook Compact Disc, various high resolution digital audio formats like DSD and 24-bit 192-KHZ sampled PCM audio – and even low rate data online streaming in MP3 and the like compared with entry level vinyl in the low bass frequencies.  

The second reason is not quite so obvious, but very important if you want your system to accurately reproduce low bass frequencies in a timbrally accurate manner, whether it is from a Fender Mustang electric bass played through an Ampeg GS-12R equipped with 7591A output tubes, an upright acoustic bass, or even a full-sized church organ with 64-foot pipes. Believe it or not, there is considerable interaction between the room and the low frequency loudspeaker units. We all know that placing the bass loudspeakers in near a wall or in a corner of the room changes the amount and distribution of the bass frequencies in the room. At low frequencies, strong and widely spaced room modes are occurring. These modes manifest itself by the fact that as we move about the listening room, some locations have a lot of bass while other locations have a lack of bass. Also, the locations where more or less bass frequencies are heard also moves around the room when you shift the position of the low frequency loudspeaker.

The problem with a three=piece system is that we only have one loudspeaker producing the low frequencies, thus the room is only excited from one point and we have a set of modes – i.e. those parts in your room where the low frequencies are either too strong or too weak – that are quite audible. When two bass loudspeakers – or two subwoofers – are placed in a room and are excited by a full stereo bass signal, each will have its own set of modes. But the benefit this time is that it is not as likely that the lack or excess of bass from one loudspeaker will fall exactly the same point as for the other loudspeaker. This would result in a considerably better uniformity of bass response is obtained when the room is excited from two low frequency sources – in comparison when excited from just one low frequency source. But if using two subwoofers is better than using just one, would using more than two provide even far better results?

A fellow audiophile of mine has a set-up that uses eight REL Acoustics Q100E subwoofers in the frontal 60-degree arc of his hi-fi rig. Four were connected to the left channel and the other four were connected to the right. According to him, this set-up was a quantum leap in terms of performance from his previous set-up when he just used two REL Acoustics Stadium II subwoofers – about four times larger in terms of volume than the REL Q100E. But how does it sound? To my ears, it is probably the most timbrally accurate set-up when it comes to producing bass below 100-Hz. Not only that, on some minimalist chamber music recordings, it transformed his listening room into a medieval era chapel where the music was recorded!!! Probably due to the room modes are now vanishing low.

Drone Cones: Rotten Bass?

Even though the theory behind passive radiator loudspeakers – i.e. drone cones - is persuasive and mathematically ordered, do they have a reputation of producing rotten sounding low frequencies?

By: Ringo Bones

Despite having a history that dates back to the early days of cone type loudspeakers, passive radiator equipped loudspeakers – i.e. drone cone equipped loudspeakers – probably gained widespread popularity around 1972 when Polk Audio founder Matthew S. Polk released his Polk Monitor 7 loudspeakers back in 1972, and since then, the global audiophile community developed a love / hate relationship around the idea behind drone cones / passive radiators. But do drone cones / passive radiators truly deserve the reputation for producing rotten sounding bass frequencies?

From a design standpoint, passive radiators are actually a form of vent substitute and thus tend to follow vented loudspeaker design methodology and design characteristics. Also known as “drone cones”, they have two very important advantages over bas reflex vent designs. First, they eliminate vent colorations – as in resonant pipe sounds – wind noises and the internal high frequency sound reflected out of the vent. Second, passive radiator / drone cone designs are practical for small enclosures – i.e. bookshelf sized hi-fi loudspeakers – when the resulting design equations call for vent lengths that exceed the internal box dimensions of the loudspeaker’s enclosure. From a design standpoint, passive radiators are also simpler to deal with, having fewer alignment algorithms that lead to calculation of losses. On the downside, passive radiators have a steeper cutoff – and this offer less transient stability – that vented / bass reflex designs (vented / bass reflex loudspeaker design already roll-off their lowest frequencies at 24 db / octave), a slightly higher cutoff frequency and greater overall losses (Q˪) than vented / bass reflex designs.

A widely popular misconception about passive radiators / drone cones is that they operate in the low frequency regions, mechanically crossing over to the main / active bass driver at a higher frequency and extend the bass of that driver. Actually, the passive radiator / drone cone operates in conjunction with the main active driver – or woofer – at low frequencies, sharing the acoustic load and reducing driver excursion, thus reducing the total harmonic distortion produced by the main bass driver. Working as a variant of a bass reflex vent, passive radiators / drone cones only add as much as they subtract. From a design standpoint, this implies that passive radiators have the same positive attributes as a bass reflex vent – such as higher power handling and lower resulting harmonic distortion.

From a historical standpoint, passive radiator loudspeaker designs were first described by Harry Olson in his patent “Loudspeaker and Method of Propagating Sound”, issued back in January 1935. Except for an article by Olson in 1954, very little was published about passive radiators / drone cones until Nomura and Kitamura in their IEEE paper in October 1973 and Richard Small’s Journal of the Audio Engineering Society paper in October 1974. At around this time, Polk audio became the well known manufacturer of passive radiator / drone cone equipped hi-fi loudspeakers when Matthew S. Polk released the Polk Monitor 7 with its famed 10-inch passive radiator / drone cone. Scores of other manufacturers have produced their own version of the passive radiator / drone cone hi-fi loudspeakers since then, like Bowers and Wilkins with their DM620i, Boston Acoustics with their compact HD9 monitor loudspeakers, Technics’ SB-M300 loudspeaker and the British – German hi  fi collaborative effort ALR / Jordan Note 7 whose passive radiators / drone cones can have various weights attached to them to match their low frequencies to the listening room’s dimensions they are intended to be used.  Given that, more or less, hi fi loudspeakers with passive radiators / drone cones produced to the years have more or less received favorable – and sometimes exemplar – reviews, then why do passive radiator equipped loudspeaker designs harbor the reputation of producing rotten, sluggish sounding bass?

Around the 1990s, almost all science enthusiasts – especially science enthusiasts who are also audiophiles – have read in various science journals, like Scientific American and their ilk, about how Mother Nature abhors three things the most – i.e. a singularity, a vacuum and an audio signal passing through a real-world capacitor. And given the steep cut-off of passive radiator/ drone cone designs, this only spells bad news from a sound quality perspective – especially in the pace, rhythm and timing department despite of their ability to produce prodigious quantity of bass in comparison to similarly sized hi fi loudspeakers.

I have an audio-buddy who has bought a second hand B&W DM620i loudspeakers back in the mid 1990s, he notices how the speakers lacked finesse when it comes to resolving subtle low bass to upper bass details. Even though I found the B&W DM629i’s overall presentation and adequate enough for casual listening of small-scale ensemble Classical Music like string quartets and the like, this won’t be the loudspeaker I’ll be using if I want to find out if a certain hair metal recording had its recording session engineer been using a dynamic range compressor with a sidechain access to “clean up the bottom end” by using the kickdrum as a “key” to limit the overall dynamics of the bass guitar – as in the compressor pushes the volume of the bass guitar down whenever the kickdrum is hit.

Loudspeakers With Rear-Firing Tweeters: The Least Room Fussy Hi-Fi Loudspeakers?

For the budget audiophile skeptical about acoustically treating your listening room, are loudspeakers with rear-firing tweeters the best value-for-money solution?

By: Ringo Bones

Budget-conscious audiophiles had always been skeptical about “pricey” acoustic room treatments. They argue that their listening rooms …” is neither a recording studio, nor a mastering or recording post-production studio…” And both anecdotal and empirical evidence seems to reinforce this very idea by the time they manage to afford those relatively pricey second hand Quad electrostatic loudspeakers either the original ESL 57 from the 1950s or the newer one and far more common ESL 63 from the early 1980s. In practice, loudspeakers with rear-firing tweeters and their more elaborate counterparts – i.e. bipolar loudspeakers that radiate sound in both the front and the back – excel at sounding as if the very recorded acoustic event is actually happening in your listening room reproduced with timbral accuracy that conventional monopolar loudspeakers (i.e. those that radiate sound only in the frontal 180-degree arc) seem to lack. But in all things audiophile, not all bipolar / dipolar / loudspeakers with rear firing tweeters are not created equal.

Back when the late, great Audio Hall Of Fame speaker designer Arnie Nudell released the Eosone RSS series back in the early 1990s, many budget-conscious audiophiles got their first exposure of a budget loudspeaker that can reproduce the timbral accuracy of the cymbals in a basic rock combo drum-kit. But there are bigger, pricier ones that are found to be wanting from this time period.

Despite of the brownie points earned for a clean, full sound in a majority of hi fi magazine reviews, the Snell Type B loudspeaker was criticized by more than a few audiophiles as having its rear-firing tweeter for being a tad too loud. Some even suggested gluing a penny over the rear tweeter in order to make it sound better. Maybe a better solution is for the designer (s) of the Snell Type B to incorporate an l-pad attenuator / rheostat in the first place to attenuate the rear tweeter to make it around 12 dB SPL quieter than the front tweeter while preserving its high-pass filter crossover point or maybe include an on-off switch for the rear tweeter in “worst-case scenarios” for an overly bright listening room.

Bipolar loudspeakers – especially those manufactured by Mirage as in their Bipolar series - gained popularity back in the 1990s due to their rather “psychedelic phasiness” that they introduce to electric guitar recordings. Though criticized for not exactly accurate, they could take this effect too far by making those early Eric Clapton recordings when he’s playing through a small-ish tweed guitar amp, most bipolar loudspeakers tend to make tweed guitar amps sound acoustically small despite of the rich harmonics of the tone being produced. And sometimes bipolar loudspeakers exaggerate the “acoustical size” of some famous electric guitar recordings – i.e. that era when Eric Clapton preferred Gibson Explorers played through Marshall full stacks.

Open baffled loudspeakers – especially ones with an open baffle midrange configuration -  are praised for reproducing female vocals with a timbral accuracy as if there was no microphone and onstage monitor loudspeakers - in short, the timbral accuracy of an unamplified female voice. Despite of their virtues, open baffle loudspeakers have one glaring shortcoming, they could sound devoid of any extraneous reverb bas in they sound drier than “Prohibition era Georgia” when paired with a very low jitter digital front end. This effect is very noticeable on electric guitar recordings that are injected directly into the mixing board with distortion and tonal effects only in the preamplifier level – as in the timbral roar of the 1980s era hair metal guitar solos championed by MTV. 

The Walsh Type Tweeter: The Greatest Tweeter Most Audiophiles Never Heard Of?

Given the rarity of still functional Infinity and Ohm Walsh loudspeakers in the 21^st Century, is the Walsh-type tweeter the greatest sounding tweeter that a new generation of audiophiles never even heard of?

By: Ringo Bones

During the 1970s, there was a legendary tweeter invented by famed audio pioneer Lincoln Walsh that was first widely used by the Ohm Loudspeaker Company given that they were the first ones to acquire the patents, Infinity then got permission to use these famed tweeters a few years later. Given that they were praised during their day as the “most realistic sounding” tweeter technology, how come the “Walsh Tweeter” is now largely forgotten?

For those who are lucky enough to still own a still functional pairs – though you can use Google to find out what are these kind of tweeters or what they look like – the Walsh Tweeter is that inverted gold cone on top of the Infinity loudspeaker box. The Walsh-type tweeter is essentially a standard tweeter motor with the voice coil and magnet attached to an ice-cream-cone-shaped thin metal with damping inside. Invented by Lincoln Walsh, the Walsh Tweeter is often associated with the Ohm Loudspeaker Company who acquired the patents on their Ohm Walsh series.

The technology seems rather simple: Instead of a traditional horizontal dome acting as a hemispherical piston facing the listener, the Walsh Tweeter was a vertical pump attempting a 360-degree sphere of high frequencies as in “omnidirectional radiation” of sound waves. Many audio manufacturers still covet the design – like Warren Gregoire and Associates with their Ikonoklast3 loudspeakers and MBL – though it struggled at higher frequencies because of its high moving mass and large shape, although the MBL’s tweeter design differs that from the Walsh-type tweeter because the MBL uses a flexible metal balloon instead of a rigid ice-cream-cone-shaped radiator. Both designs have trouble reaching past 12,000 Hz and is often used with a “conventional shaped” dome tweeter being used as a “super tweeter” to generate signals above 12,000 Hz.

Given their limitations, anyone lucky enough to own a still functional Ohm F loudspeaker swore that the Walsh Tweeters are the ideal tweeter for reproducing Classical string quartets or similar small ensemble Classical works, although some say Jimi Hendrix sounds “more interesting” on a pair of Ohm F loudspeakers. The same holographic front-to-back imaging thing also occurs on a pair of more recent Ikonoklast3 loudspeakers and similar MBL Radialstrahler 101 loudspeakers.