Monday, March 31, 2014

Logitech Harmony 650 Universal Remote Control Review

As your collection of audio gear grows, there comes a time when you get tired of dealing with the pile of different remote controls on that table next to you. Have you ever wanted just to listen to music or watch a television program and could not find one of them? The frustration can be overwhelming and the clutter is something I personally despise.

So I decided to finally do something about the clutter. But where does one start? Organization? You bet! I sat down and created a short-list of what features were important for me to get based on my previous experiences with poorly-designed universal remote controls. The "must have" features I came up with are:
  • Learning mode for atypical control codes (use the existing remote to train the new remote)
  • Long battery life (possibly rechargeable)
  • User friendly and intuitive (MUST have an ultra-high spousal-approval factor [aka SAF])
  • Small, preferably controllable from one hand
  • Does not forget its programming when quickly changing batteries
  • Capable of controlling both IR and RF gear
  • Easy to program
  • Easy to access repetitive functions
  • Does not require any device to be network connected
  • Best bang for the buck (read under $300, preferably under $100)
While some allow computer programming, this ability to me is optional. And although I need it only to control IR devices, many newer products are RF controlled and it would be nice to plan for the future. With this shopping list of features in mind, I decided to look into what was available.

The problem with remote controls is that there is no standard. Unlike HDMI, USB, and other interconnects, remote controls use a variety of digital command sequences based on a slurry of methods prepared by a variety of engineers from a plethora of manufacturers, none of which are involved directly in the industry to which the remote is used. For example, one manufacturer creates a remote control device that is used on a toy car and this same electronic device is used on a television or personal media streamer without conflict by just tweaking a design parameter. Convenient for equipment designers, yes, for consumers, not so much.

And there seems to be no relief in sight...or is there. Logitech, a company who first entered the consumer market with its computer mice, has grown its product family in many ways, each with its successes and failures. But this market seems to need someone to take the reigns and get a hold of simplifying complicated issues and they have done a decent job. After evaluating the higher-end offerings, I decided to spring for their more budget-based product, the Harmony 650 available for well under $100.

This remote offers PC-based programming and an online tool that allows you to research which devices it can control, something you really need to investigate before buying anything. And with all of my gear on their list, I was at least confident that training it from the manufacturer's remote would not be necessary (although it can do this too).

I was frustrated after the first software installation and control setup since it frankly did not program the remote as I had instructed it to do, but after removing, rebooting, and re-installing the web app, all went well. (BTW, to reset this remote, remove one battery, hold down the "All Off" button, and reinsert the battery. This will enter SAFE MODE on the remote allowing it to wipe the current training and relearn everything.)

What I really liked about this remote is the four one-button tasks. Say you get up early one morning and have not drank your favorite morning beverage reviving your weary eyelids and encouraging your sluggish body to move. The Harmony 650 has a button labeled "Listen to Music" and once properly programmed it will allow you to do just that with the push of that button. What a concept! Now, a word of caution, you must keep the remote pointed at the gear for a while so that all of the commands can be executed at the time required. For example, my OPPO BDP-105 takes its time getting to the HOME screen so the remote control understands this and pauses the appropriate amount of time before telling it which source to select. Brilliant! High marks for the Logitech's attention to the SAF.


Full-Color Logitech Harmony 650 Display and Four Task Buttons

However, and this is a big however, this remote forgets its programming functions. Yes, you heard me correct, with the next day's use, this remote control forgot how to turn everything on. While it did recall how to switch individual devices on/off, doing so from one of the four-button tasks did not reliably work. Use of the HELP button did resolve the issue for the moment, but after another all off/on cycle, back to the same old forgetful behavior and I have to retrain it...again, and again, and again. I don't know about you, but having to reprogram a remote almost every time you use it is not why I buy a universal remote control.

On the rare occasion that is does remember to turn everything on properly, accessing a device to perform another function (like changing the source of the OPPO) forgets the mapping to the volume control on the preamp (duh!). So going back-and-forth between devices becomes essential but again for a remote of this level it should not be unnecessary.

So, the bottom line is this: the Logitech 650 has the right idea but the sample I received did not work as advertised. For this reason, I am going to give these folks the benefit of a doubt that for some unknown reason I received a lemon (lemons happen). However, for this same reason I cannot give this remote a glowing review.

Until Logitech steps up to the higher-quality-control plate, I would look elsewhere for an under $100 universal remote control.

Yours for higher fidelity,
Philip Rastocny 

I do not use ads in this blog to help support my efforts. If you like what you are reading, please remember to reciprocate, My newest title is called Where, oh Where did the Star of Bethlehem Go? It’s an astronomer’s look at what this celestial object may have been, who the "Wise Men" were, and where they came from. Written in an investigative journalism style, it targets one star that has never been considered before and builds a solid case for its candidacy.

http://www.amazon.com/dp/B00QFIAC3G

My other titles include:

·  Extreme Audio 1: House Wiring·  Build an Extreme Green Hot Water Solar Collector
·  Extreme Audio 2: Line Filtering·  The Extreme Green Guide to Wind Turbines
·  Extreme Audio 3: Chassis Leakage·  The Extreme Green Guide to Solar Electricity
·  Extreme Audio 4: Interconnect Cables·  Meditation for Geeks (and other left-brained people)
·  Extreme Audio 5: Speaker Wires·  Althea: A Story of Love
·  Extreme Green Guide to Improving Mileage·  Build an Extreme Green Raised Bed Garden
·  Extreme Green Organic Gardening·  Build an Extreme Green Rain Barrel
·  Extreme Green Organic Gardening 2012·  Build an Extreme Green Squirrel-Proof Bird Feeder
·  Build an Extreme Green Composter·  Extreme Green Appliance Buying Guide

Copyright © 2015 by Philip Rastocny. All rights reserved.

Monday, March 17, 2014

On Esoteric Wire...


Conductor types and purity have often been a topic of hot debate where on side endorses use of exotic materials and another snubs up their noses at any audible benefit. To set the historical record straight, below are some notes that should help you understand why this topic seems to rear its head so frequently.

Back in the early 1970s, someone questioned one of the most overlooked and common components in every audio system: the material used for wire or conductors. Since once cannot escape wires in interconnects, speaker cables, speaker voice coils, phonograph cartridges, internal chassis wiring, and circuit boards, this seemed to be a logical area for investigation. If there were an advantage to moving to a different material, there were a diverse number of places it could be implemented. A few companies introduced speaker wires and interconnect cables in response to this curious question touting this or that advantage because of this or that feature. In reality, most claims were fruitless and sheer marketing hype.

This doesn’t mean that there were not differences between conducting materials – there are drastic measurable differences – but when marketing spun the assets of these features they turned out to sound more like snake oil than science. After a prolonged learning curve, these marketing goons learned what did and did not work when pumping up the benefits of their products and today buzz words associate fair, good, better, and best conductors. (BTW, I love these goons since they are the people responsible for advancing sales and therefore the advancement of the high-end itself, but often question their choices of words or stand on reasoning.) Before jumping into the fray of these buzz words, let’s review a bit of historic around conductor materials.

When wires were first needed, scientists analyzed which pure materials (not alloys or processed metals) had the least opposition to electrical flow and in the order of their “conductivity” (electrical resistance per unit length) are from best to worst are: silver, copper, gold, aluminum, zinc, and nickel. So the best conductor was silver with copper a very close second. Two characteristics of silver eliminated it from the desirable material list since it was expensive and it easily oxidized. Copper was therefore the number one choice (see a highly descriptive resistivity table for all electrically conductive elements in the periodic table at http://hyperphysics.phy-astr.gsu.edu/hbase/tables/elecon.html#c1).

With the introduction of computers and high-speed electrical signal technologies, coated copper materials were developed to improve high-frequency characteristics. Called “wire-wrap wire” this coated copper also came in a new manufacturing process introduced in 1975 called OFHC (oxygen free high conductivity). Here, oxygen normally encountered in is production is eliminated from the extrusion process thereby improving its conductivity. Another refinement also improved conductivity by eliminating normally-encountered impurities (called high-purity or HP). Again, audio manufacturers swarmed behind this new process and introduced a variety of cables featuring this new type of copper.

Recently, a further copper refinement process was patented by Professor Ohno of the Chiba Institute of Technology in Japan that reduces the number of fractionated crystal structures and other impurities. Termed the Ohno Continuous Cast (OCC) copper, this metallurgical process uses a heated mold for casting and extruding, with cooling taking place in a separate process. The result is ultra-high purity copper with a larger crystal size.
Copper Type
Oxygen Impurities (PPM)
Hydrogen Impurities (PPM)
Traditional (TCP)
200-500

OFC
10
0.5
LC-OFC


OCC
5
0.25

With these results, the OCC process creates "ultra-pure" (UP), also known as “ultra-high purity” (UHP), copper and the abbreviation for this material is UP-OCC. (See http://www.copper.org/publications/newsletters/innovations/1997/12/wiremetallurgy.html for more information on current high-technology metallurgical manufacturing processes for copper.)

Oxygen Free Copper (OFC): Oxygen free copper was developed in Japan around 1975 as it became increasingly apparent that sound quality was related to the quality of copper and the processing used during cable manufacture. OFC is produced is a carefully controlled oxygen free environment resulting in a significant reduction in oxygen content (10 ppm). There are fewer crystal boundaries in OFC which results in much higher performance than TPC where the numerous crystal boundaries cause a degradation of the audio signal.

Linear Crystal Oxygen Free Copper (LC-OFC): In 1975 Hitachi improved the OFC process to further reduce impurities and crystal boundaries. The patented LC-OFC process developed by Hitachi re-heats the copper following extrusion which reduces impurities between the crystal boundaries as the copper crystal expands. This in turn leads to a longer overall crystal length. A typical crystal in a 1mm diameter LC-OFC conductor is 130 mm long which can be compared to typical crystal length of 4mm long in TPC conductors.

Ultra High Purity Oxygen Free Copper (UHP-OFC) is processed much in the same way as OFC but is also subjected to a further Zone Refining process (developed by William Gardner Pfann). With Zone Refining the purity of the copper crystals is increased by drawing a narrow molten region of a crystal. This molten zone is moved along the crystal (in practice, the crystal is pulled through the heater). As the molten region melts it leaves a wake of purer material solidified behind it. The impurities concentrate in the melt, and are moved to one end of the conductor whilst it is being drawn.

Ohno Continuous Casting (OCC): In 1985 Professor Ohno from the China Institute of Technology developed his patented method for the extrusion of a grain free copper wire. When a pure metal solidifies, its crystals grow in a specific geometrical pattern (typical to that metal) emanating from a nucleus, rather like the dendritic growth pattern of a tree. The size of the metal crystals grown can be varied by repeatedly annealing metal such as is done in the LC-OFC process. The structure of a strand of copper may be likened to that of a bag of sugar. Every grain of sugar has a crystal boundary. In a conductor, these crystal boundaries (potential barriers) act as a non-linear resistance to the flow of electric current. It follows that, the fewer the boundaries, the less the effect there is on an electric signal as it propagates from one end of the conductor to the other. The Ohno Continuous Casting method re-heats the extrusion as the molten copper is forced out of the mould and very slowly and gradually draws the grain or crystal down the conductor's length, creating a 'single crystal structure'. The typical crystal length of OCC copper is more than 200m.

So what’s the conclusion from this? In 350BCE, Aristotle wrote that women have fewer teeth than men and everyone did not question Aristotle because…well he was Aristotle, someone much smarter than most ever would hope to be just do not question these sort of things. But one day, someone got a brainiac idea, “Let’s count them!” What a concept. And sure enough, men and women both had the same number of teeth proving that even the great Aristotle could make a mistake. WOW! This means that even the brightest minds can learn a few things since their followers are taught to blindly do what they were told…until someone doesn’t. This is how advances are made – by questioning authority and finding out if what was once believed to be true still is - or is not.

Technology advances every day and sometimes several times a day. Our understanding of the world and how it works constantly evolves and with it should our reasoning for accepting old facts. What was once understood by one set of physical laws will always change once our understanding of these laws advances. It was once believed that the world was flat and the earth was the center of the universe. Anyone who disagreed was considered at the least off his/her rocker and at the worst a heretic and put to death. Skeptics have a purpose in keeping those of us who wish to investigate our changing understanding in one word "honest." Truth must prevail but even skeptics can be biased since they adhere to what they know – which may be an old understanding to which they unquestioningly now regurgitate the words of their teachers.

What I am trying to say is this: keep an open mind and even though the reason someone states that this is why something like wire sounds better than this other conductor, it is the goons who write the words you read (or even the idea maker her/him self) that may not be quite right. This does make the advancement any less justified; it is that we as human beings always struggle explaining what is going on with a new discovery of change. One day, Einstein, Stephen Hawking, every skeptic, every critic, you, and I will all be proven wrong. It is inevitable; all we need is more unconstrained time and open-mindedness for future generations to clearly understand why.

The best position you can take is that of neutral; neither for nor against but completely open minded. You count the number of teeth, you listen to the differences, and you make the choice. Don’t let biases influence your decisions and a better sounding system can result. Give that linear-crystal wire in our tonearm a shot, give that interconnect cable or power cord a try, and give that new CD player a go. All you can do is be wrong, and what’s wrong with that? No one ever advanced anything without making a few mistakes. Go ahead: fail and learn something new about what does not work. Then, try again.

Yours for higher fidelity,
Philip Rastocny 

I do not use ads in this blog to help support my efforts. If you like what you are reading, please remember to reciprocate, My newest title is called Where, oh Where did the Star of Bethlehem Go? It’s an astronomer’s look at what this celestial object may have been, who the "Wise Men" were, and where they came from. Written in an investigative journalism style, it targets one star that has never been considered before and builds a solid case for its candidacy.

http://www.amazon.com/dp/B00QFIAC3G

My other titles include:


Copyright © 2015 by Philip Rastocny. All rights reserved.

Thursday, March 13, 2014

URL to Bozak B-199A Thiele-Small Parameters

Some of you have requested information about T-S parameters for the Bozak B-199A woofer. Below is a link to the only site I know of containing this information:

http://petoindominique.fr/php/mysql_listehp3.php?marque=BOZAK

While the data is incomplete and uses many calculated values, until another source is found this is it.




Yours for higher fidelity,
Philip Rastocny 

I do not use ads in this blog to help support my efforts. If you like what you are reading, please remember to reciprocate, My newest title is called Where, oh Where did the Star of Bethlehem Go? It’s an astronomer’s look at what this celestial object may have been, who the "Wise Men" were, and where they came from. Written in an investigative journalism style, it targets one star that has never been considered before and builds a solid case for its candidacy.

http://www.amazon.com/dp/B00QFIAC3G

My other titles include:

·  Extreme Audio 1: House Wiring·  Build an Extreme Green Hot Water Solar Collector
·  Extreme Audio 2: Line Filtering·  The Extreme Green Guide to Wind Turbines
·  Extreme Audio 3: Chassis Leakage·  The Extreme Green Guide to Solar Electricity
·  Extreme Audio 4: Interconnect Cables·  Meditation for Geeks (and other left-brained people)
·  Extreme Audio 5: Speaker Wires·  Althea: A Story of Love
·  Extreme Green Guide to Improving Mileage·  Build an Extreme Green Raised Bed Garden
·  Extreme Green Organic Gardening·  Build an Extreme Green Rain Barrel
·  Extreme Green Organic Gardening 2012·  Build an Extreme Green Squirrel-Proof Bird Feeder
·  Build an Extreme Green Composter·  Extreme Green Appliance Buying Guide

Copyright © 2015 by Philip Rastocny. All rights reserved.

Wednesday, March 12, 2014

Bozak Rebuild Project - Part 10

In my previous attempts to upgrade a pair of Bozak B-302a speakers, I fiddled with a second-order crossover network in hopes to improve the sound. Using some trickery, I was able to get the RTA measurements to "look" right but the resulting sound was really off the mark. Testing each driver independently revealed where this network design was and was not working.

In review, the original crossover network from Rudy Bozak used a first-order Butterworth design (BW1). I revised this to a second-order Bessel design (BE2) hoping that the steeper crossover slopes would attenuate the influence of one driver on another (e.g., the midrange on the tweeter and vice versa). While it improved the sound, individual driver in-circuit measurements assured me that steeper slopes were required to truly prevent this interaction.

A third-order Butterworth design (BW3) is currently in place yielding remarkable results and the old Bozak B-200Y tweeters have retired and Peavey RD1.6 ribbons now are featured in this design. Crossover points are BE2@450Hz and BW3@2,348Hz and the sound is quite smooth through 12KHz. Using higher-quality capacitors on the RD1.6-side of the crossover network added another level of refinement that blatantly pointed out the shortcomings of the old Clarity SA capacitors. So the old adage of "you get what you pay for" held true here as it does so often when buying other high-end gear.

The sound of the system is currently captivating with a huge soundstage extending far into the side walls adjacent to the speakers. Front-to-back depth is also surprising and image stability is spot-on regardless of what instrument is playing or where the engineer placed it with her/his mixer's pan pots. Studio and hall ambiance is also easily articulated as is inner detailing, always a plus to any audiophile's ears.

There is a downside to of all this, or rather there is a potential to make future improvements. Presently, the speakers exhibit a certain sterility from this latest round of refinements for which I am having a difficult time tracing down its source. This same issue reared its ugly head in previous upgrades and changes, and  now it has returned. Backing out of changes one step at a time and then returning it to normal takes time and so far I have not discovered the source of this problem (most likely revealed in Part 11). And lastly, even though the RTA measured better at the start of this round of changes, there are certain things that have greatly improved that do not conform to what the measurement shows. In other words, the RTA only tells part of the story.

Below is a summary of how RTA measurements changed through three phases of the crossover network's evolution while moving from the starting point (before), interim 1, interim 2, and final design for this network. Although work focused primarily on frequencies above 2.3KHz, it is interesting to note the influence the changes made to the tweeter had on the woofer.

Here is the "before" RTA graph of the system using all Clarity SA capacitors in a BE2 crossover network on both the W-M and M-T points (6-27-13):


BE2@450Hz and BE2@2,348Hz Clarity SA Capacitors, no HF compensation

The system sounded good up to about 8KHz where the magical tinkles of tambourines and cymbals were just muted. You could hear them but the SPL was just mismatched. Plus, there was an annoying 6-7KHz sibilance making prolonged listening difficult. (Also note the dip at about 500Hz).

Here is the "interim 1" graph of the crossover network using all Clarity SA capacitors in a network using two different network designs: a BE2 on the W-M point and a BW3 on the M-T point (7-1-13):


BE2@450Hz and BW3@2,348Hz Clarity SA Capacitors, no HF compensation

The sound was better in that the top octave started to materialize and the annoying sibilance was gone. The sparkle was still lacking and the smoothness in the midrange had something missing that I just could not put my finger on. (Note the increased dip at that 500Hz point.)

Here is the "interim 2" graph of the crossover network using a variety of Mundorf Supreme capacitors I had lying around on the RD1.6 portion of this crossover network and using a Clarity SA HF compensation capacitor (2-10-14):



BE2@450Hz and BW3@2,348Hz Mundorf Supreme Capacitors with HF compensation
With this really uniform SPL measurement, I was anxious to hear what the system sounded like. I was greatly disappointed. Although things sounded "smoother" they did not sound real. There must have been a huge amount of phase distortion introduced by the HF compensation capacitor below its crossover point that contributed to this very edgy sound. (Note however that the 500Hz dip is gone.)

Here is the "final" graph of the crossover network using a better selection of Mundorf Supreme capacitors (lower parts count) on the RD1.6 portion of this crossover network and shifting the compensation point up just a little (3-10-14):

BE2@450Hz and BW3@2,348Hz Mundorf Supreme Capacitors, higher HF compensation

The sound was initially VERY pleasing with midrange detailing I had never heard from this system. Especially noteworthy is the clarity of the planar tweeter yielded providing very low distortion and accurate reproduction of the timbre of individual instruments. However, the HF compensation point still needs more adjustment and that is where I am today. (Note that the 500Hz dip is still mostly gone and other bass peaks and dips are now present.)

I have experimented with many different component values for this HF compensation point, some with resonating effects causing buzzing and some with other unique colorations. But progress is coming and with each change I hear more and more. When the final level is chosen,I will post it in Part 11 of this series.

Before this phase of changes, I was satisfied with the sound of the system but I knew it had greater potential than the crossover network allowed it to deliver. Two changes made a big difference in overall clarity: first, moving to a third-order network on both the midrange and tweeter legs, and next moving to the Mundorf Supreme capacitors. HF compensation brought sparkle back into the top octave but this is at a price of phase distortion and the final crossover point for this "kick" is yet to be determined.

For now, I am thoroughly enjoying the sound of my system, especially its huge soundstage and definition. Much like removing layers of an onion, each time I settle on a change in design, my system reaches down into the truth of a recording. If a production is weak, I will hear it. Conversely if a recording is superior, it stands out and grabs your attention.

It's nice to dim the lights, put on a small jazz combo, and imagine who may be sitting at the table next to yours in that dingy dark basement. Presently it is raining very hard and the sound from the roof and windows reminds me of the old Leon Russell song "Manhattan Island Serenade" (Carney album). Leon sings of a van broken down on the highway with the sound effects of wet tires rolling by. I think I'll spin this and enjoy the weather.

Will there be a Part 11? Why not? Click this link (link to be updated soon) and see if anything else has percolated to the surface!

See also Part 1Part 2, Part 3, Part 4, Part 5, Part 6, Part 7, Part 8, and Part 9

See the Thiele-Small specifications for the Bozak woofer here.

Yours for higher fidelity,
Philip Rastocny 

I do not use ads in this blog to help support my efforts. If you like what you are reading, please remember to reciprocate, My newest title is called Where, oh Where did the Star of Bethlehem Go? It’s an astronomer’s look at what this celestial object may have been, who the "Wise Men" were, and where they came from. Written in an investigative journalism style, it targets one star that has never been considered before and builds a solid case for its candidacy.

http://www.amazon.com/dp/B00QFIAC3G

My other titles include:

·  Extreme Audio 1: House Wiring·  Build an Extreme Green Hot Water Solar Collector
·  Extreme Audio 2: Line Filtering·  The Extreme Green Guide to Wind Turbines
·  Extreme Audio 3: Chassis Leakage·  The Extreme Green Guide to Solar Electricity
·  Extreme Audio 4: Interconnect Cables·  Meditation for Geeks (and other left-brained people)
·  Extreme Audio 5: Speaker Wires·  Althea: A Story of Love
·  Extreme Green Guide to Improving Mileage·  Build an Extreme Green Raised Bed Garden
·  Extreme Green Organic Gardening·  Build an Extreme Green Rain Barrel
·  Extreme Green Organic Gardening 2012·  Build an Extreme Green Squirrel-Proof Bird Feeder
·  Build an Extreme Green Composter·  Extreme Green Appliance Buying Guide

Copyright © 2015 by Philip Rastocny. All rights reserved.