Q&A # 214 - January 26, 2001

Staff

Q I now have a 15", dual voice coil, passive subwoofer which I would like to power with an auto-on subwoofer amp. Would a monaural amp work and if so how  is it wired? Any suggestion on a particular product?

A The dual voice coil can be wired to a stereo amplifier if you wish. This is for when you want the signal from two channels to feed one subwoofer. However, I would suggest using just one of the voice coils with a mono amplifier unless it is an amp that is rated into 4 Ohms, in which case, you would wire the two voice coils in parallel with one another. Typically, that would reduce the impedance to 4 Ohms, assuming the impedance of each coil is 8 Ohms. Some power amplifiers have 15 Volt triggers for auto-turn on, but what you really need to be concerned about is raw power. Here are some possibilities for mono amplifiers: Audio Source AMP5.3 - 250 Watts - $249.95;     Speaker City IKG5230 - 230 Watts - $225.

Q I have a turntable hooked through a preamp mixer going through an Aiwa stereo. When I copy records to cassette, the quality is poor and I have to turn up the volume almost all the way to hear it normal. I wouldn't question this other than the fact that it did not happen with my old stereo. Do you know why this happens?

A Assuming your recording level meters are set correctly (peak at 0 dBU), I can think of only one possibility: You might be using the wrong kind of tape or the wrong bias setting for the tape. Some recorders have various settings for the different types of cassette tape. If the wrong setting is used for a tape, the resulting recording can sound terrible. On less expensive recorders, it might only accept one kind of tape, so check your user's manual to see which kind is supposed to be used.

Q I am in the market for a DVD player. Currently I have a Pro Logic AV receiver, but I soon plan to upgrade to a Dolby Digital/DTS AV receiver. I have looked at DVD players that are:

1. Built in Dolby Digital and DTS output

2. Dolby Digital and DTS ready

3. None of the above

Specifically, I have looked at the Sony DVP 560 (with decoder) and the DVP 360 (without). The DVP 360 is not listed as Dolby Digital/DTS ready, but does have the Dolby Digital/DTS output (maybe that means it is "ready").

I have been told that the Dolby Digital/DTS decoder players and Dolby Digital/DTS ready players would not be of use to me now with my Pro Logic receiver, and would also not be needed once I purchased a Dolby Digital/DTS AV receiver. Therefore, it sounds like the least expensive DVD player is the right choice.

It does seem that I will at least need the Dolby Digital/DTS outputs once I upgrade my AV receiver, but then again, maybe not.

My only advice has come from salespersons at high volume retail electronics stores (e.g., Best Buy, Circuit City), and they didn't seem to be sure about the advice they were giving. The advice may have been valid, but I want to be sure, so, what do you think?

A All new DVD player models have both DD and DTS digital out, and all new model receivers have DD and DTS decoding built-in, as far as I know and have seen. There is no such thing as a DD/DTS-ready player, since "ready" usually means you have to add an outboard something or other, such as an HDTV tuner to an HDTV-ready DTV, or a DD/DTS decoder to a DD/DTS-ready receiver that has the necessary 5.1 analog input jacks. What differentiates players these days is not having DD/DTS digital output, but rather such things as component video output and progressive output. So, you can buy the most basic DVD player you want, but check to make sure it does have the DD and DTS logos on the front, because the transition to having the decoding on all players is just happening now. Secondly, you can still enjoy surround sound with DVD movies using your old receiver, by plugging the two-channel analog outputs on the DVD player into one of the input sets on your receiver. Then, when you get a new receiver, you connect the digital output jack from the player into a digital input on the receiver. Receivers these days will automatically detect the type of signal (DD or DTS) and convert it to analog sound appropriately. The only thing that 5.1 analog outputs on DVD players are useful for now is DVD-A and multi-channel SACD (besides connecting to an old receiver that does not have DD/DTS built-in, but does have 5.1 analog inputs).

Q I'm in the process of upgrading my home theater system to support DD 5.1 and DTS. My Series 1 Bose Lifestyle 12 can be upgraded for 500 dollars but will only support DD 5.1. At this point, I'm leaning towards a new receiver with PSB speakers (Alpha-A/V and Alpha center for the front and the Alpha minis as surrounds with the SubSonic 5 Sub.) I haven't chosen a receiver at this point, but it would be in the three to five hundred dollar range. Should I upgrade the Bose system or start from scratch?

A Well, since you want DTS, it sounds like the best idea is to get a new receiver for about $500, along with the PSB speakers. I am not quite sure why Bose does not include DTS, since modern chips decode pretty much everything all in one chip.

Q I have a Pioneer receiver that is about 3 years old. It is Dolby Pro Logic only. What is the best audio setting for me to use when I watch DVDs? I have Infinity Center and Reference Series loudspeakers in front,  and Infinity Minuettes in the rear, and no subwoofer.

A Pro Logic is decoded from two-channel stereo. You can use it with any two-channel source, including CDs and the two-channel output from DVD players. In my experience, many of the DSP modes that come with receivers sound very artificial, and this problem occurs mainly with music. In fact, with something like piano, the CD will often sound better in two-channel rather than Pro Logic. However, with movies, some of the DSP modes can sound rather nice, and the ones I particularly enjoy are "Pro Logic Enhanced", and something called "70 mm Movie" or similar name. You just have to try all the modes out and see which ones you like.

Q I'm in the process of renovating a portion of my home to be a home theater. I have the know how to do all the labor and building, but I am utterly lost in the field of electronics. I've seen photos of housing for all the theater components, and I cant even identify all the things I'm going to need. It's going to be a front projection system with 100 inch diagonal screen. I know I'll need speakers and a receiver to connect them too, but I want them all to be able to be controlled by a remote or small panel, and I haven't a clue!

A The answer to your question depends greatly on your budget. With a 100 inch screen, you're going to be spending a handsome sum on the display device itself to get something decent, from thousands to tens of thousands.  You'll probably also want to get some kind of video processor, as "standard" sources display 480i, and 480 lines interlaced on a 100 inch screen isn't all that great. Displays such as LCD and DLP will perform de-interlacing, but whether it will do a better job than something like a DVDO IScan or a Dwin Transcanner is something that will depend on the display device. You'll probably want a good screen as well, such as Stewart Filmscreen.

So, you do know that you need a receiver. Depending on the kind of performance and output you want, you may also consider an outboard amplifier to take the burden of powering the loudspeakers off the receiver.  Almost all receivers are a bit compromised in the power amplifier section not only because of price, but because of space. Good power amps that supply 5 channels of amplification usually start weighing in at 50 pounds due to the heft of the power supply. Many top 100 pounds. An outboard power amp isn't a necessity, but it's a very nice step. All you need to move into an outboard amp from a plain receiver is a little more rack space and ventilation, and well as "pre-outs" (for all channels) on the receiver.

If you want to take it the next step in audio processing, you can get a dedicated preamplifier/processor. These are typically more expensive than a receiver, and do more or less the same thing, except that they have no power amplifiers at all included, and may not have a AM/FM tuner section.  Because all of their resources are devoted to a more specific task, the separate preamp/processor has the potential to be a better performer than the receiver used solely for switching and control. However, because the market is geared toward making many more receivers than separate components, a good receiver will provide far more "bang for the buck."

You probably know, or have heard, that a subwoofer is more or less a must for home theater, and it is a very cost effective and practical way to maximize the performance of the system. Getting a tower-type loudspeaker that can equal the extension and output of a good subwoofer generally gets very expensive, so that it usually makes practical sense to buy the main and surround speakers for mid-bass, mid-range, and treble quality first, and let the subwoofer handle what it excels at. Subwoofers that actually go deep enough to deserve the name, and can handle any kind of reasonable output, usually start at around $600 or so. If you need the deepest, most powerful bass reproduction, you will spend thousands.

For source components, you'll want a DVD player with component outputs, and then whatever components you need to play whatever software you have. For instance, if you have CDs, get a CD player. Not too complicated.

In terms of your control panel, if you're looking for a flexible, relatively affordable IR remote, look at the Phillips Pronto. You can design your own touch panel pages, learn/exchange IR codes, create macros (inserting page flips anywhere in the macro) and do it all with a PC, and actually find many discrete IR codes (like input and power commands) at http://www.remotecentral.com  that will make life easier when it comes to making those macros work.

If you really want to get into some cool control systems, you can look at AMX or Crestron. AMX is the more "industrial" side of Panja http://www.panja.com, although I like using it for residential systems. Panja also has a Phast division, which is alright for simple multi-room music and HVAC integration, but between the two, I much prefer the flexibility of the AMX stuff.  Panja also has the new "Netlinx" stuff which spans the two, and offers integration as well as some internet services built in.

Crestron offers products of similar capabilities, with a different look and set of options with their products. Both the Panja and Crestron can control pretty much anything that was meant to be controlled in an A/V system. They can spit out IR signals, with a carrier or not, close relays (and subsequently control voltage triggers), sense contact closures or voltage triggers, communicate with RS-232 or RS-485, parse that data, and keep track of pretty much anything you tell them to.

I believe Panja has a deal that for roughly $1,500 or so, where you can order a controller that will come pre-programmed for the equipment you specify, complete with a touch panel and RF receiver. But the application itself, I think, is limited primarily to IR control. If you're interested in such a thing, get in touch with them and hash out the details.

However, to get into the really cool toys, takes a little more cash.  For instance, the AMX and Crestron gear, for what they do, are priced competitively with each other. For a one-way, RF system, with a controller that has 6 ports for two-way serial communication, 6 ports for either IR or one-way serial communication, 7 contact closure/voltage sensing I/O ports, and I think 6 or 8 relays for whatever purpose, you're looking at roughly $3,500 in equipment. From there, you've got to program it. You can do it yourself, which I admit is fun, but you're then looking at potentially $1,500 more or less to get the panel designed and the controller programmed, based on a single theater system with a few cool toys. Throw in two-way communication and fancier gadgets to integrate, and the fun goes up, but so does the cost. It gets expensive, but if it's done well, you'll never have to think for yourself again, or at least about how your theater system works, or for that matter, when to lower the lights and close the shades.

Forgot to mention, in case it interests you, you can also enable control of the theater or the house via the web, so that you can watch movies without even being there! Isn't that great! Maybe just a little funny too. The AMX touch panel design software will let you save touch panel files as web pages, writing the HTML for you.

We're actually considering putting Stacey's army of madness (his A/V gear and related home appliances) on such a control system, partly so he can automate his shades, but also so he can access features available only through the RS-232 commands for his equipment, so that he might be able to do more thorough reviews.

I've never actually integrated a popcorn machine, but if they can automate dog food dispensers, I can't see why that would be very difficult. The hard part would be writing the program to know how each individual in the seat liked the popcorn served, though I suppose you could simply enter the preference through the menu in the touch panel.

P.S. - Here are a couple of links for popcorn machines at good prices: http://www.upop.com/   and  http://www.snappypopcorn.com/machines.html . I found some other links too, but the prices vary by several hundred dollars for similar products. Check lots of URLs before you buy. Be careful about purchasing too much popping oil at one time. It spoils if it sits around for a long period. Coconut oil has the best flavor, but it has a lot of saturated fat. You can get sunflower oil which has a lower saturated fat content.

Q I am designing a media room for my home theater in my new home and have a few questions about floor coverings that produce the optimal sound qualities. Do carpet or hardwood floors with area rugs produce more audiophilic sound quality? Also, what dimensions are ideal for the room. I am considering a room 14' X 30'. I have a home theater system with Polk center, rear, and subwoofer and KEF 107s as my front speakers. I use a Denon AVR 5600 as my amplifier and have a Panasonic DVD player and Mitsubishi 36" TV.

A If you've got a LOT of area rugs, particularly on the floor between you and the speakers, then I'd go for area rugs, so long as you're going to have some kind of absorption/diffusion along the walls in the form of drapes, book cases, or similar things. The idea is to make the room not too dead, but also not an environment that allows long echos (try slapping your hands in different locations) or much in terms of direct reflections from your loudspeakers (i.e., floors, ceiling, and side walls). The placement of furniture, and the shape of the room, as well as the placement of your speakers, will also shape the room response, particularly in the bass region. Experimentation is the only proven method, so do what you can to keep your placement options relatively open.

Q I was thinking that either the Sony S7700 or Marantz DV7010 (or DV7000) DVD players would be a good choice for me and was looking for reviews about these players.

Fortunately, I found the great reviews at Secrets. I'd like to thank you for these reviews. However, there are still some trade-offs, which make it hard to decide which one to pick :)

It would be great if you can give me some advice. My system is as follows:

Receiver: SONY STR-V333ES
Speakers: Klipsch Synergy Quintet

Well, my budget for a DVD player is $1000 (max, I'm just a graduate student). I could spend some more but that would be too good for my system.

A Most players now do a pretty good job on the video with the majority of DVDs that have been released. For the budget you mentioned, the Toshiba SD-6200 is one of my favorites. The new Denon DVD-2800 ($799) is currently under test by Stacey Spears, and it appears to have tremendous promise, so wait until he writes his review.

� Copyright 2001 Secrets of Home Theater & High Fidelity
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