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Q I'm planning on upgrading my system for HT, although my primary concern is audio. My system is quite old (15 to 20 yrs), but still sounds fine. I have Dalquist DQ-10 speakers, and the preamp and amp are by Frank Van Alstine (solid state MOSFET stuff). I'll be buying a sub soon (liked the Velodyne FSR-15), and will upgrade the speakers in about a year. Probably to Magnepan MG3.5s, although I'm a little concerned about dynamics - they don't play very loud.
I'm wondering how the Yamaha DSP-A1 compares to separates. As a point of reference, once you get into the high end stuff (Levinson, AR, Bryston, etc.) I've never really been able to hear any substantial differences. Also, would the Yamaha do the Magnepans justice?
Another HT related question: can the center channel sound be routed to the fronts? Systems with center channel speakers always sound strange to me.
On a separate note, what's all this about
DVD lasers being designed to read the narrow tracks of DVDs? We're
talking digital data here - with
error correction. I would think that either the laser (and rest
of the transport) faithfully retrieves the data or not. And any
sonic differences would have to be due to the DAC and/or analog
sections. Am I missing something here?
A The DSP-A1 is a gemstone among pebbles, but its strongpoint is its processing sophistication. The power amplifiers inside are about the same quality as other mass market receivers, a little more power, but about the same quality of power. Magnepan speakers are very popular, but they are 4 Ohms nominal, and most of them are well below 90 dB/w/m sensitivity. Therefore, the DSP-A1 amplifiers will not drive them very well. I would suggest an outboard power amplifier, connected to the DSP-A1 pre-outs, if you want Magnepans. At very low volume, most amplifiers do sound very much the same. It's when you turn up the volume that you will begin to hear differences. The mass market stuff tends to get mushy and harsh at high volume. High performance power amplifiers will retain dynamics and musical detail at high volume.
Routing the center channel sound to the front left/right is easy. With Pro Logic, set the center channel to "Phantom". With DD and DTS processors, the center channel setting may be called "None". The problem in the past has been that receivers tended to have less power in the center channel amplifier, and consumers tended to spend most of their speaker money on the front left/right, while allocating $79 to the center speaker. The irony is that the center channel gets most of the sound, whether it is Pro Logic, DD, or DTS. Now that this has been recognized, receivers come with equal power in the center, and there are lots of high performance center channel speakers to choose from.
With DVD players, the laser is narrow to fit the narrow track of data pits on DVDs. Part of the way the laser stays on track is that feedback tells when the laser is hanging off the edge of the pit rather than being in the middle of the pit. The width of a CD player laser is designed for the width of the CD pits. This is not so easy with the narrow DVD laser which can be off center of a pit on a conventional CD without hanging over the edge of the pit. Think of it like driving a car. If the road were so wide that you could not see the right or left edges, it would be much more difficult to stay in the middle, and you would have to make sudden swerves once you came close enough to the edge to see it. For a DVD player with a CD, the linear direction sways back and forth from being right down the center. This alters the timing of the data, and therefore, jitter results, giving the sound a hard edge. I suspect that there are no more bit errors than with a regular CD player, but the timing errors (jitter) are probably horrendous. I am hoping that jitter reduction components will help solve this problem. With some of the newer CD player technology, there is a RAM buffer (specifically for jitter reduction) that is fed from the transport, and the data are reclocked before heading out to the DAC. In this case, the timing errors coming off the disc are corrected. If jitter still occurs, it would be a result of faulty clock integrity (several possible sources, including the video section), or a faulty input/output.
There are tweaks that affect the mechanical
portion of the transport which can affect the sound, but it's
not because of any reason involving the
rate of data retrieval. It usually involves a change in the load
on the motor which changes the spectra and/or amount of noise
which eventually
leaks into the power supply of the master clock, which affects
the clocks performance, which certainly will generate jitter.
Noise and/or bandwidth limitations in the output/cable/input
chain to a separate DAC and/or processor can also contribute to
jitter. As much as I believe that the standard two -channel 16/44.1
music format could use a good boost by both more channels and
a higher information rate, and that jitter can be a significant
problem (and will be a more significant problem if you want to
achieve truly higher resolution with higher bit and sample rates),
I also believe that roughly 98.5 percent of CDs sound bad to audiophiles
because:
1. Audiophiles have their own personal expectations of what things "should" sound like. Many times the real thing (an orchestra in the room), if they closed their eyes in a dead room and were told it was a recording, wouldn't sound "live" enough. They're used to either the magnified or recessed perspective they've grown accustomed to and/or euphonic distortions which make the experience more pleasant. Two-channel stereo is limited enough that it's natural to want some enhancement. Otherwise, many might find it pretty boring.
2. Many recordings suck. Crappy microphones, inept mixing, overdubbed, over/under processed, ridiculously eQ'd, unqualified producers and/or unqualified (or just accommodating to the producers) engineers. You can still enjoy them if you like the music, but the sound is ruined, and no CD player, no matter how good, can fix that. Bad CD players, or even "good" CD players intentionally tweaked by non-linear circuits and/or proprietary DSP methods can hide the fact a bit. They may sound better to some listeners, and the ones that I heard (the Audio Electronics CD-1 and most of the WADIA stuff) could sound fabulous, but required a lot of tweaking in the rest of the system that certainly wasn't in the interest of accuracy.
3. Some CD players (a few esoteric ones) have horrible RF filtering in the reconstruction stage. In itself, it's inaudible, but can set some equipment into oscillating like the dickens.
4. Cheap analog stages and/or poor noise isolation are present in some CD players. A good CD player doesn't have to be ridiculously expensive, as shown by a couple of Marantz and Sony models, though excellent digital performance usually is. Expensive digital, though, can be awful, though it's amazing what casework and marketing can accomplish to bias opinion. After all, if it costs $10,000, it should be better than the $1,000 player, right? Well, we'd hope so, but . . .
Q I
recently purchased the "Air Force One" DVD and am playing
it on a Toshiba SD2108. I noticed that in the widescreen format,
the displayed picture is missing the bottom third of the original
movie picture. On the full screen version (fit for normal TVs),
I can see the complete vertical part of the picture. I thought
I should see MORE of the original movie in the widescreen format,
not the other way around! I checked another copy of "Air
Force One" on a Pioneer player and found the same thing.
This seems like a crappy deal when one is expecting true "widescreen."
Have you seen the same thing in the "Air Force One"
DVD or other movies?
A This
is the result of "Air Force One" having been filmed
in Super 35 rather than Panavision. This means that the movie
was made using non-anamorphic lenses, with the full film frame
being exposed, and then when the release prints were made, only
the center strip of image was transferred, giving the theater
image a more rectangular, higher aspect ratio (ratio of image
width to image height). When the movie was released to rental
stores, the missing pieces from the top and bottom were put back
in, so that it would fit a full TV screen. When a movie is filmed
in Panavision, there are no missing pieces from the top and bottom
to put back in, because anamorphic lenses are used. So, when you
see the movie at home on TV, in full screen format, you are actually
seeing only about half of what you saw in the theater, since the
left and right portions have to be chopped off. See the Television
section of our Primer in Volume
1, Number 1, 1994 (updated recently), which will explain all
of this in more detail, with examples. In essence, you will often
see MORE in the full TV screen version of non-anamorphically filmed
movies than the widescreen version (the exception would be in
those movies that have a lot of computer graphics), but always
LESS in the full TV screen version of anamorphically filmed movies
than the widescreen version. This is the case for 4:3 NTSC TVs,
but it will change forever once HDTVs arrive with their 16:9 aspect
ratio.
Q Where
can I find information on do-it-yourself acoustic panels?
A Get
in touch with some of the manufacturers who make the materials
for such projects. These would include http://www.auralex.com,
http://www.sysdevgrp.com,
and http://www.rpginc.com.
You will find that there are two types of treatments, one of which
is diffusion and the other is absorption. Total room treatment
is a combination of the two.
Q
I am in the process of purchasing
a preamp/processor to add to my system, and during my search I
have found out that some preamps/processors do not have analog
pass through. How important is analog pass through and what does
this have to do in relation to the units internal DAC? Also does
this affect some of the formats you talked about in Q&A #
72 particularly 24/96 audio DVDs? Lastly, does this affect existing
equipment like say a CD transport and VCR?
A
What you are referring to is
relevant to those preamps that convert the analog signal to digital
(using an A/D converter) before doing things like adding DSP.
It is then converted back to analog, using a DAC, before it goes
to the power amplifier. The Yamaha DSP-A1 processor/amplifier
does this, using 24 bit conversion. There is two channel analog
pass through on this unit, if you just want the analog signal
to go through without A/D, processing, and D/A, but some units
don't have pass through as you said. The effect on the signal
varies with the quality of A/D and D/A, and since no system is
perfect, there will be degradation. You have to weigh the benefits
(DSP) vs. cost (degradation) when choosing such equipment. When
the audio signal is digital going into the preamp, such as the
digital out from a CD player or DVD player, the preamplifier does
not use the A/D since the signal is already digital. It applies
decoding, then DSP to the various channels if you wish it, then
the DAC does its thing, and the analog out goes to the power amplifiers.
The two channel analog out from a VCR would go through A/D, DSP,
and then D/A. For 24/96 DVDs (DADs), the DAC is in the player,
because copyright restrictions have not been finalized, and you
have to use the two channel analog audio out jacks from the player.
Once this problem is solved, the 24/96 digital bitstream will
be sent to processor/preamplifiers just as would a 16/44.1 bitstream,
for decoding.
Q
I have a chance to get the
Carver AV-705x five channel power amplifier for $850. However,
which one is a better choice: Yamaha DSP-A1 or a combo of Carver AV-705x and
some pre/pro (the pre/pro should be under $1,500)?
A
The DSP-A1 is such an amazing
product, that I think you would be happier in the long run with
the DSP-A1 rather than a lesser capable processor and outboard
amplifier. Stick to 8 Ohm speakers though.
Q Currently I own a Marantz CC65 CD Player. I am considering an upgrade. My other equipment consists of the following:
Acurus RL-11
Acurus A200
NHT Series 2 (2.5i currently)
Mirage BPS-150
Kimber PBJ
Kimber 8TC
I have demoed Arcam, Acurus, Cyrus, and have yet to find something noticeably better to my ear. The above all sound either too undefined, non-dynamic, or boomy compared to the Marantz and for my taste. I like accuracy, real fast transients, tight bass, crisp highs, warm mids.
Can you suggest anything? My room is not
carpeted, not treated, but even with PBJs, I don't find it bright,
just dead-on musical. Is there something better, or is this as
good as it gets? I don't mind if it is. One dealer really likes
the Sonic Frontiers Anthem CD1, but the other I deal with finds
that tube sources degrade over time, and sells a lot of McIntosh.
Go figure! I would like to spend up to $2K Canadian but only if
noticeable.
A
If there is one thing Marantz
does well, it is CD players. There is a difference among players,
but apparently, these differences are not palatable to you. It
shows that you don't have to spend a fortune on any particular
component to get something you like. It also shows that preferences
are not necessarily directly related to price. Keep your $2,000
in the bank.
Q
If I connect the output of
my LD player into my TV input, and then from my TV output into
my preamp auxiliary input, will I still get AC-3 surround sound
assuming the disc being played is AC-3 encoded and my decoder
is able to decode AC-3 materials? Would there be a loss in signal
this way as compared with connecting the LD player directly to
the preamp?
A
In order to utilize AC-3, you
need an AC-3 (DD) decoder, either in your receiver or in a separate
decoder. With LD, you additionally need an RF output on the player
and an RF demodulator in the receiver. This converts the AC-3
RF signal to digital so that it can be decoded. For Pro Logic,
all you need is the two channel analog stereo output from your
LD player into your receiver. It can pass through the TV and out
to the receiver for Pro Logic decoding if you want, but it would
probably be better to put it through the receiver first, then
the TV (using the "Effect Off" switch on the receiver
to pass the two channel analog on to the TV without decoding it
into surround sound). If you connected the RF output or digital
output from your laserdisc player to the TV, you would just hear
some noise, no surround sound. So, for AC-3, connect your LD player
directly to your processor, not the TV.
Q I've been reading some of your product reviews on multi-channel power amplifiers - specifically the Krell KAV-500 and the CinePro 3k6. The Krell is 100 watts/channel into five channels and the CinePro is 350 watts/channel into six channels. I'm looking for something in the middle - 200 watts/channel into five channels. I'm currently using a Yamaha RX-V2092 which is 100 watts/channel (five channels plus the separate front effects channels) and would like to double my power output. My speakers are Definitive Technology BP2002 mains, C1 center, BP6 and PF12 rear, and minimus 7s for the Yamaha's front effects channel.
The speakers are rated by Def Tech for max
amplification from 175 - 300 (depending on which speaker), so
I'd like to go with 200 watts/channel
with a five channel amp. I'd love to get the CinePro, but would
be fearful of destroying my "under-rated" speakers before
I could afford to replace
them. For the front effects channel, I'd go with a separate two
channel 100 watt/channel amp, although, would it be feasible to
use the CinePro's
sixth channel to run both front effects speakers (all of my speakers
are rated at 8 Ohms)? Also, the BP2002s have internally amplified
subs for
LFE, but I will eventually add a separate amplified sub, just
for LFE, so I don't need the sixth channel for a passive sub.
So, any recommendations on a 200 watt/channel 5 channel amp, or
any better alternatives based on my current set-up, would be appreciated.
A
First, having 350 watts per
channel is not a problem for your speakers, since you don't have
to turn the volume all the way up (you never should anyway). With
normal listening 25 watts into each channel will give you plenty
of volume, and the amplifier will have lots of headroom for dynamics
that are often demanded with intense music and movies. However,
if you really want the 200 watt/channel amplifier, Sunfire's Cinema
Grand is rated at 200 watts into 8 Ohms. Also, CinePro has a new
five channel amplifier in that same power range, and it is much
less expensive than the 3k6.