Home Theaters

When I started thinking about this, I was sure that everyone who was interested in quality reproduction (home theater) would have no need, as they would have purchased a large screen that already had an ATSC (read digital) tuner, built in. Then I started thinking about some of the televisions I have seen friends and family buy in the last few years, and realized that many did not. Some have televisions that used a modular approach, saying that when the DTV format was finalized, the tuner module for that would be available. As anyone who pays attention knows, these sort of promises usually go unfulfilled. Other televisions were sold with the ability to do a high resolution (for the time) but with an analog tuner only. Still others were those sets that were sold as computer monitors, with an NTSC (read analog) tuner included, and no provision to remove the analog tuner, and replace it with an ATSC model.

Further, there are those who have a smaller set in a bedroom, with a nice audio system connected, and no problem with the idea of high quality SD (standard definition) in that room. Another group of people will be those who don’t wish to throw out a perfectly good television, for reasons of being green (I’m certainly in this group, as there are 3 televisions in this house that have really fine SD pictures).

A word now about a few things. First, there is a website established, as well as a toll-free number available, for getting the coupons to help defray the cost of the purchase. Each address is able to request 2 coupons, which are worth $40 dollars, making the purchase less a problem for the less than wealthy. Next, there are supposed to be tens of manufacturers for these digital converter boxes, yet I could find mentions of 5 manufacturers, and 9 models total, in a somewhat exhaustive search on Google. Hardly the turn out predicted by the Consumer Electronics Show, this last January. Last, it has been estimated that there might be a shortage of these boxes, mostly by the manufacturers, who are probably hoping to gain a sale of a more expensive television, if they artificially create a shortage situation. I’m fairly certain some consumer group will come up with a class action lawsuit concerning lack of a product made necessary by a government mandate.

  the RCA offering, pictured both horizontally, and vertically, with remote

the Magnavox offering

  one of the 2 choices from GE (other than the aggressively ugly looks, it should be almost identical to the RCA and Magnavox boxes, as they all are trademarks owned by Thomson Electronics)

Another thing to think about is the Consumer Reports article that compares the units available. They choose the RCA, but the reasoning is not clear why the choice is made. More telling is that many comments were made on that article, with one standing out for me. Apparently most of the units do not allow analog pass thru of signals, so using those boxes daisy-chain style (like many people used to do with VCRs) is not possible. This is possibly (well, probably) a cost consideration, but I prefer to think that it forces many to use the non-RF connections found on every box, to achieve the best picture quality, and by pass what must be an incredibly cheap RF modulator.

There are the choices currently available from Echo Star, Zenith, and a little known company called Insignia, but no pictures or fact sheets could be found on them. As Echo Star gets some of its stuff from Thomson, the EchoStar  units are probably very close, if not identical to one of the known Thomson models.

The only thing to distinguish the aggressively ugly GE model, other than aesthetics, is the fact that it purports to have Dolby Surround outputs. That would certainly mitigate the ugliness, if the output quality was good.

the government issued cards to help with converter box purchase

Unless you are wanting to get the digital content immediately, I would recommend waiting to let a few more models come to market, and perhaps a few problematic models will be removed from the market. For those wishing to buy immediately, get your card(s), and purchase on features, as there doesn’t seem to be much difference in performance - so its standard or Dolby audio that makes the difference.

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As I have been looking now, for some time, to try to find a speaker that will satisfy the sound quality I desire, with the aesthetics I need (for the better half), and the price point I must have, it seems that nothing will do but a kit or a design I make myself. Sure, there are lots of inexpensive speakers, but they either sound really bad, or look like refugees from a bad contact paper fantasy, or both.

always fun dealing with other people’s ideas of good design - but sometimes compromises must be made. this cabinet could use some good bracing, so it’s not the best choice

Although I will be paying through the nose for assembled cabinets, it is necessary, as I will not have access to the proper woodworking tools, and I plan to save  money with the design and wiring of the cabinets, and I am still looking for deals on drivers. 

Raw drivers of quality have gone through the roof, as the dollar is weak, and all the good ones are built offshore.  Name a quality driver manufacturer, and I can usually name the country of origin. In no case is it the USA. You may say that you are aware of several manufacturers of assembled speakers that are made here in the United States, and you would be right. However, unless I have missed a change recently, any  domestic, quality manufacturer  doesn’t sell the raw drivers, or acts as if the drivers were made by Congressional committee using 24k gold. In other words, the pricing is stratospheric.

In the 80s and 90s, there were several purveyors of raw drivers that both had good quality  and fair price. Now, it is down to only three that I can name, and the last I looked, one of them was not looking healthy. Those providers are Madisound, located in Wisconsin, Speaker City, located in Burbank, California, and Zalytron, located in  New York.  Zalytron wasn’t looking so good last time I checked.

some designs with Morel drivers - the far right example is a D’Appolito design

I will also be looking for a  recent copy of  ‘The Loudspeaker Design Cookbook’. I believe the author is Vance Dickason, but I’m not sure.

  It was a while ago that my older copy was ruined in a flood.  The cookbook gives help with the math behind the Thiele-Small calculations, and offers several choices of speaker designs. I will be building a variation of the D’Appolito design, which uses a vertical woofer - tweeter - woofer layout, with a cabinet that is barely wider than the woofer diameter.  This design  concept is not new, and several quality manufacturers have made models using this concept.  Since the big boys have tried it, in large scale, and more importantly, since I have heard the results, it is a design I am comfortable with, and will fit my price considerations.  I also will let you know that I have a pair of the Original VMPS Subwoofers, and will be using those, crossed over at about 80Hz, so ultra low bass will not be something the satellites will need to produce. Another consideration is the fact that using this  speaker design will allow me to build a 5th speaker identical, and flip it 90 degrees to be the center channel  for the system. No problems with  changes in drivers or response that way. Simple.

a Dynaudio woofer - notice the large magnet, the cast basket, and the large voice coil - all good things making for a great end product

I always wanted to build a set of speakers using  Dynaudio drivers, as I have heard several of their designs, including the mighty Duntech Sovereign, which used all Dynaudio drivers. The results were spectacular for a non-planar speaker design, and the dynamics were phenomenal! Because of the decision of Dynaudio to remove their raw drivers from the market, I am looking at Morel drivers, which are made in Israel. The designs are copies of the more popular Dynaudio drivers, and as such use large magnet structures, and also large voice coils. (By large voice coils, I mean  there are 6.5" midwoofers that have 3" voice coils.) This makes for high power handling, great heat dissipation (the drivers also use ferrofluid), and very little cone breakup. The only thing about the Morel line of woofers is that the line all tend to have rather high Qts, meaning that the drivers are most effectively used in a sealed box.  This leads to larger box size than I would like, but you can’t have everything.

I am hoping to have my parts chosen soon, and then I will cover the build. Next installment, choosing the right components for the crossover.

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Some may remember that I reported upcoming upgrades for owners of DirecTiVos in the late months of last year, that were to have taken place by now. I was merely reporting what had been presented to the public, not knowing it was all to change. Some would say we were lied to, and I would agree. It appears that for all the benefits of DirecTV, the purveyors are still bowing to pressure from the media content makers (or are they - could this simply be a money grab by DirecTV, and a very convenient shift of blame? It will be interesting to see if the same thing happens to those who have DVR units connected to Dish Network.)

 poor remote, poor feature list, lackluster performance - the advantage that DirecTV had with the DVR service is eroding from great to merely good

This time around it has been announced that owners of the markedly inferior DirectDVR units will no longer, after April 15, be able to store downloaded pay-per-view items. After a period of 24 hours, the content will simply be wasted space on the hard drive. This is sad, for no matter who is doing it, it shows that the whole point of Digital Rights Management is simply greed. It is not enough for a person to pay for programming, knowing that on the DirectDVR it is locked down tight so that there is no way it can be easily removed from the original drive it was recorded on - now the purchase is only good for 24 hours. If something happens that causes the family to not be able to view the purchased content within that time, too bad. Greed, nothing else.

 these units are not as  glamorous as the DirectDVRs, and the peanut remote is ugly, but functionality is orders of magnitude better

It is already bad enough that DirecTV customers must endure the spectacular failure that is the successor to the DirecTiVo, and those of us who have both are reminded daily of the bad programming of the newer units, as well as the total lack of ergonomic considerations.

further reading an be done here 

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Damping factor is something that most enthusiasts who have been around high fidelity for less than ten years know nothing about. Why you ask? From my perspective, it would seem that anyone interested in a high damping factor would not be looking for anything in the under $1000 category, as most amplifiers in that class have a poor one, and simply producing audio of any quality is a remarkable achievement.

this Threshold S500 has a damping factor of well over 1000:1…beauty, eh?

The term damping factor refers to a ratio of the internal impedance of the amplifier to the characteristic impedance of the speaker driven by it. Obviously this would vary widely, as each speaker has its own characteristic impedance, and also, since speakers are a reactive load, it would be hard to specify across the frequency spectrum. In order to be uniform, the speaker load of 8 ohms, purely resistive, is assumed.

Quality amplifiers will have a damping factor of at least 100:1. Many really exotic, and very high quality amplifiers will have a damping factor of 1000:1 or more.

By now, I’m sure many wonder why this ratio is called damping factor, and why anyone concerned with great sound should be concerned with it. Damping factor affects the way the music sounds, as it refers to how well ‘damped’ any cone movements are. The larger the ratio, the more capable the amplifier is of controlling the movement of the speaker drivers. It is most apparent in the bass, but has an effect all through the audible range.

When listening to a system with an amplifier of high damping factor, the bass will be extended, but very clean. The woofers will not overshoot, and any muddiness in the bass will be due to the program material, more than the amplification chain. This is not to say that an amp of high quality will make the bass of a Cerwin Vega (a speaker known for boomy, muddy bass) turn into the bass of a reference series speaker, but a marked change will be observed, and heard.

this Cerwin Vega is popular with the crowd that likes the tizz and boom sound, but a good amplifier will tame much of that boom!

As complete specifications are harder and harder to find for any audio or video equipment these days, it might be difficult to assess damping factors. Any piece of equipment that is worth your time will have a manufacturer willing to send you a more complete set of specifications, so do a little looking, or writing, and see what you find.

When talking about damping factor, it is imperative to know that each part of the amplification chain is significant. This is why quality speaker cable of sufficient size is necessary for quality reproduction. Now, some will tell you that huge rope-like wires are needed. While that would be nice, and WOULD make a difference, it is impractical, and most significant others would frown on both the aesthetics and cost of such a move. On the other hand, I would never think of using less than 16 gauge multistranded copper wire for any installation, and any move you can make upwards in size will bring dividends in sound. Some wire suppliers, like Monster, have larger gauge wire made to look as inconspicuous as possible, so that may be the ticket for your installation.

a couple of examples of high quality speaker cable, which helps maintain the high damping factor, AudioQuest, Kimber, and Monster all make great speaker cables.

Damping factor is not the be-all-and-end-all of amplifier specifications, but it goes a long way toward getting good quality sound.

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Yes, that’s the slogan dreamed up many years ago by a purveyor of margarine, with an irascible Mother Nature roiling when given margarine disguised as butter. The idea was that originator of the commercial had come up with a butter substitute that, as seen later in the ad, was completely acceptable to the old gal. Well, just as then, we know today that not many things are made by man that duplicate something in nature well enough to fool anyone really paying attention.

should you really try to annoy her?

After looking at the latest PC Magazine, I was amazed that early in the magazine an ad appeared for some new trickery from those evil trolls from Massachusetts. The speakers are hardly larger than a man’s closed fist, yet the claim of incredible sound quality is in the ad. ‘What is new about that?’  you may say. Many know that Bose has been playing acoustic tricks on people since the inception of the company, so that is not new. What is new is that the company is getting more and more bold, as its attempts at fooling the public are less and less veiled, and the prices for this ‘magic’ are at stratospheric heights.

in all their glory! Bose Compact Music Monitor

Later in the magazine, a review of the ‘NEW Bose Compact Music Monitor’ tells me exactly what I knew already. Bass is non-existent, and mids and highs are only acceptable. All of this at a price of only $400. What a deal!

The Bose 901 - the original trick!

Back in the time of the original 901 series speakers, it was considered a decent feat to get 9 inexpensive 4" drivers, and an equalizer, to sound somewhat like what others were doing with a woofer, a midrange, and a tweeter. Oh, and they looked cool, as many people would hang them from the ceiling. They sounded impressive, and so many people purchased them, soon tiring of the exaggerated sound. That same ‘punchy, sparkly sound’ has followed the company’s products through the years, with one or more acoustic tricks used in each set of speakers made.

The thing is, after 30-odd years of trickery, shouldn’t either the sound quality get better, or at least our perception of it?

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In an interview with Microsoft, Reuters reports that there is no movement toward a change to a Blu-ray player for the Xbox 360. This is odd, as moving to a medium of higher density would make sense, with the titles expected soon to need more than the space of  one standard DVD.

will this one find its way to the Smithsonian?

In that same article the Microsoft person contacted stated that eventually there would be a move to Blu-ray, as that would be a natural move. How strange that Microsoft isn’t using its clout to keep HD DVD as the standard for Xbox. Perhaps Toshiba was not willing to pay enough tribute to the oracle at Redmond.

Toshiba has really made some big mistakes here, not the least of which is removing HD DVD from the market completely. As I had stated before, it is a format that had no serious flaws, it was simply the wrong horse to back. The total cost to Toshiba for this mistake is estimated to be around 1 billion dollars. Toshiba is a huge conglomerate, but a billion dollar mistake is not pocket change to any non-government entity.

With at least one studio supporter of HD DVD, and a few hundred thousand drives sold as backup and distribution possibilities, HD DVD could have lived a normal, albeit compacted life span. As a backup medium, it might actually have had a very long life - the drives being less expensive to produce, and the small number of discs needed to do a backup of large hard drives would have been spectacular reasons for this usage.

can’t you imagine a single disc holding 15GB as backup, that costs under $120?

One thing that no one is willing to divulge is if anyone is going to release the post-mortem on HD DVD. Was its demise simply a matter of timing? Did the big push in the last three months of 2007 help or simply delay the inevitable? Many times a push such as the one noted gets so many units in the hands of the public that ‘critical mass’ is achieved, and the technology takes hold. On the other hand, the extreme price cuts may have convinced the movie studios that margin could never be restored, and HD DVD would remain a loss leader.

Toshiba has chosen to eat the loss, but it really should shop the technology around a bit, before destroying the assembly lines. After all, anyone who has read about, or remembers the Edsel  knows that it too, was a product that was basically good yet failed to impress the public.

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Up until now, I have kept up with the progress of the Home Theater PC, but resisted the temptation to build one. Several things have aligned recently to change my mind, and make serious perusal of the parts necessary to build one a priority.

  maybe not the performance king any longer, but very respectable

The demise of television programming of quality, the newest series of central processing units that are highly efficient, and the latest generation of motherboards that allow for a neat package that wraps high performance and low heat and noise all together in one great package all contribute to the push for a home theater PC.

AMD has been getting the brunt of comments lately that compare processing power, but still it is a company that knows how to produce a great processor for a price. Any of the low power X2 series of processors will make a great beginning for our machine. These are available in 45W, 65W, and 95W total thermal dissipation packages. Depending upon your needs, any of these will work - a good choice for 1080i resolution would be the X2-5000+ or greater. This will allow for other processes in the PC to complete in the background without causing jerking or other interruption of the program.

a Gigabit offering of the 780G chipset, a very good candidate for your HTPC

With the new series of 780G series motherboards, a big change has taken place. Up until now the user has had to choose between onboard graphics, which are less than spectacular, and an add-in  graphics solution, which takes lots of power, requiring a much larger power supply, and generate major amounts of heat, requiring lots of active cooling. For a gaming PC, it is no big deal to add a noisy fan to maintain the temperatures of the CPU and GPU, but in an HTPC, anything that makes noise is going to detract from the theater experience, and also compress the absolute dynamic range, as the fan noise raises the noise floor of the system. With the 780G series, a budget video card can be put into the graphics slot, and the onboard graphics can be used together to form a (since we’re talking about AMD only) Crossfire graphics solution. Lots of video processing power with very little noise and heat!

Another very nice thing about the 780G series motherboards is how dense the features have become. These microATX form factor boards have up to 12 USB ports, and many have Firewire as well, allowing for easy connection to a digital video source, such as a DV camera. Most of the boards have a gigabit Ethernet port, so streaming across a home network is easily done. Along with the x16 PCIe slot, the boards usually have a couple of PCI slots and a x1 PCIe slot. This will allow for a couple of television tuner cards, and possibly a wireless NIC, if needed.

the Ultra MicroFly makes a great HTPC case, and is good for LAN parties too!

All of this can be accommodated in a small case, allowing for a very easily placed package. My personal choice would be the Ultra MicroFly case, or perhaps one of the lookalikes, such as the Apevia XQ-Pack. The reason I mention the Ultra first is that it is 1.5" longer than the others of its type, and that allows for a full size power supply. The case will hold a couple of optical drives, a couple of hard drives, and either a media reader, a floppy, or a Zip drive.

high quality, major warranty, and little to no noise - what more could you want? The nuclear self powered PSU has not been invented yet, until then, PC Power is ‘da bomb’

A good choice of power supply would be a PC Power and Cooling Silencer 470, which will power all that can be put in the case, including a monster video card, should you decide that gaming is something else you want the HTPC to do.

Any good 20" LCD will make this HTPC worthy of doing almost any other computing chore when not showing showing movies or recording television programs. Marrying these pieces to Windows XP MCE will yield a very easily used computer with multiple personalities - which in computing terms is a good thing. On the other hand, using any of several flavors of Linux will allow for all that XP MCE does with the exception of playing some Windows-only games.

Have fun, I know I’m going to - the parts collecting begins now.

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Careful as a person may be, there comes a time when a speaker will either start making strange, unnatural noises, or, worse yet, go strangely silent. If you are present when the problem occurs, you probably have a clue or two about what went wrong. It could be an overzealous rendition of the Telarc 1812 Overture CD, with less than judicious placement of the volume control, and some disastrous results when the cannon shots rang out. Perhaps watching a movie about earthquakes has taken its toll on your subwoofer. Or possibly nothing spectacular has happened, and you are quietly wondering why your speaker has gotten as quiet as your thoughts.

different cone speakers

First, checking to see that the problem is not further up the chain is important. The easiest way to determine if the problem is at the speaker is to switch the channels. Change right with left and see if the problem moves with the change. If it does, the speaker is the problem. Now checking individual drivers is important. Sometimes midrange drivers, as well as tweeters, will be fused, and a repair is as simple as a fuse replacement. A word of caution - it may seem like the best thing to do is replace the blown fuse with a larger one, it is not. The speaker designers do a fair amount of calculations when sizing fuses, so replacement with the same size fuse is the best course of action.

speaker crossover assemblies          

If there is no fuse on the driver, it’s time to take a cheap multimeter (which you can borrow, you need not buy one) and check the voice coil for continuity. No continuity means that the voice coil has been fried, and its time for a new driver. If there is continuity, it is time to investigate the crossover. Unless you are able to identify a blown capacitor, or less likely, a bad resistor, chances are it is now time to button up the speaker and let the pros take over. If however, you find a bad part, it is time to identify the resisitor or capacitor, and get the specifications of the part. If you are able to solder, you can put identical parts back into the crossover. If you cannot get identical parts, again, it’s time to let the pros take over. Going back to the driver, replacement must be with the same driver, usually obtained from the manufacturer of the speaker.

this is a handy friend when trying to track down speaker problems

If you are trying to replace a speaker that is no longer available, you can call upon a reconing service, which will replace the cone and voice coil, making the speaker usable again. If you are particular about the sound (as I am) it is best to have mirrors reconed at the same time. That is, if you have a blown midrange in the right front speaker, it is best to replace the left front midrange at the same time. If you have the choice of changing the surround of the cone from foam to butyl rubber, with assurance that the important parameters of the speaker will be the same, or very close, go for it. Butyl surrounds will last much longer and will suffer less from ozone degradation. (For many older speakers, the surround breakdown is not a result of misuse, but age, and the polluted environment many people must endure.

Ohm Walsh speakers, with exotic drivers - you’re not going to get a replacement from anyplace other than Ohm.

If you happen to be lucky enough to have a speaker with more exotic drivers, that have gone bad, it is more difficult to do much other than get an exact replacement. Be aware that during different runs of speakers, the drivers may be slightly different, so getting the exact part number is essential. The internet has made contact with the various manufacturers much easier, and sending an e-mail with exact needs can save loads of frustration and telephone hold time.

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With the change this weekend to daylight savings time, the thoughts of spring and the cleaning that follows entered my head. Every year the spring brings the thoughts of evaluation and upgrade, and before a reasonable evaluation can take place, the system must be at peak performance.

  it may not yet be spring, but when the time changes it seems like it

This means that the electrical chassis of each component must be opened, cleaned of accumulated dust and any other debris, and checked for any other abnormal changes. I usually make a day of it, as thorough cleaning involves a quick vacuuming, then a fine cleaning with either canned air or cotton swabs.

a good swab collection comes in handy for many things

Disc trays accumulate a lot of fine dust at the rear, and all other places where the discs don’t ride. I usually use some swabs to thoroughly clean the glides of the trays, and then use the appropriate lubricant on the moving parts. In most cases petroleum jelly works best, as it doesn’t evaporate onto the spinning discs, and doesn’t degrade the plastic or metal parts of the disc trays. A word of caution here - if there are any rubber parts in your tray assembly, do not use petroleum jelly, as it will destroy the rubber. I have only seen a few mechanisms that use rubber parts, but it pays to check. If your mechanism uses rubber, try using Armor-All on the rubber parts, and leave the petroleum jelly alone.

this stuff works for scratchy pots, and old television tuners, too

If, by chance your preamplifier or amplifier knobs have started to give a scratchy noise when turned, a trip to the electronics store for some ‘tuner cleaner’ will be in order. The name ‘tuner cleaner’ comes from the days when television tuners were mechanical items, before the days of ICs and the varactor. Anyway, a good spray to the affected potentiometers while moving the control through its complete range is what is called for here. 

Next, it’s time to check all the speakers for wear and tear. Each surround should be checked, then the cone should carefully be moved through its range of motion to make sure that the voice coil is not rubbing. Any electronics in the speakers, such as a subwoofer amplifier, should get the same check that the other amplifiers get. Now would also be a good time to vacuum the speaker grilles - you will be amazed how much dust these things can pick up.

removing oxidation without removing metal is always good!

Last, the interconnections should all be removed, cleaned, and reconnected. This applies to speaker wires as well. If you use gold spades, banana plugs, or tips, all that should be required is a gentle swiping with a damp cloth. If you are using brass, or bare copper connections, its time to bring out the Brasso, or other metal polish, and work on your connections. The oxidation that occurs over a years time degrades the sound significantly, and your ears will thank you after all your connections are once again clean.

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in posting. The flu bug has been busy keeping my whole family down. This has gotten to be number one in the all time flu bouts I’ve ever had. Between my own sickness and that of my children, I have been unable to do any of the reviewing I had promised.

Now I am on the tail end of the flu, with only a cough to remind me of the bad times of the past couple of weeks, I am again planning several trips for review of new hardware. I also have the beginnings of a few articles, started when I was too ill to finish, but now looking like they will be completed  in a day or so.

There is much to talk of, and now that I can type without too much trouble, the flow of information will again begin.

Later

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