Yamaha RX-V2500 Receiver Review

It's been over two years since a Yamaha RX-V series receiver has occupied Reference System 3. As you can imagine, I was pleased to be able to integrate the RX-V2500 and see what surprises Yamaha has come up with in the last several revisions since my experiences with the RX-V3000 receiver.

Having just reviewed the Denon AVR-3805, I was anxious to test out Yamaha's YPAO system to see if it was a more productive setup and parametric EQ option for basic room correction. I also wanted to see how well the 130 watts/channel amplification could drive the 4-ohm RBH Sound 1266-LSE main speakers which require quite a bit of power to sound their best.

Yamaha has certainly not been sitting on its laurels of late. In fact, Audioholics completed a rather thorough review of the RX-V2400 receiver when it came out and I was pleased to note the following improvements from that model:

• Additional 10 watts/channel for 130watts/channel (20Hz - 20kHz, 0.04% THD, 8-ohms)
• DTS: Neo 96kHz
• Pure Direct Mode
• GUI Interface
• Updated YPAO Equalization modes and shortened test time
• Manual PEQ settings
• Subwoofer phase select
• Additional component video input
• New remote control with backlit buttons
• Shuttered optical connections
• Improved components

The Yamaha RX-V2500 receiver was powering RBH Sound 1266-LSE Signature Series speakers in a 12 x 20 listening room in Audioholics' Reference System 3. Below is the configuration utilized for this review:

While I'll cover more of these topics in greater detail later, there were some things that quickly jumped out at me upon first setting up and using the Yamaha RX-V2500 receiver.

For tweakers and seasoned home theater enthusiasts, no one can calibrate your system better than you - right? Well, let's start with a manual setup of the receiver, then. The new GUI allows you to set up Sound, basic System Configuration, and Receiver Options.

I started with the Basic System Configuration options and set my system to the following using an SPL meter and tape measure. I utilized the Yamaha's internal test tones which had to be enabled via the GUI:

Surround Back: None
Crossover frequency: 60Hz
Bass out: SWFR
Subwoofer Phase: Normal

Manual setup couldn't be any easier, save for adding voice commands, and the whole system was configured in less than 10 minutes. That even included renaming several of the inputs and adjusting their volume trims to blend the levels of my various sources.

If you think Manual Setup is easy, try plugging in the microphone , pressing one button and waiting approximately 3 minutes - now that's easy! Yamaha's Auto Setup feature is accessible directly from the GUI and is very literally a one-step process. It can also be configured to limit setup to all or some of the following parameters:

• Wiring
• Distance
• Size
• Equalizing
• Level

Of these options only wiring (potentially) and equalizing cannot be done with visual inspection, test tones and an SLP meter. What's really convenient and impressive is that you really can trust the Yamaha to do an accurate job of setting the basic parameters. The EQ settings generated by the YPAO system we'll discuss a bit further on. Here is the comparison of the results I achieved manually compared to the Auto Setup system:

Notably, the Auto Setup was with 0.5dB of my manually configured settings. This difference is possibly attributed to my physical presence during measurements as opposed to an unobstructed microphone, or it could simply be a difference between the calibrations of the Yamaha microphone and the RadioShack SPL meter.

Note: The Yamaha Auto Setup incorrectly stated that my main speakers were both wired out of phase. This was not entirely incorrect. In fact, the RBH 1266-LSE 12" drivers are wired out of phase for correct acoustical summing at the crossover point of the 12" aluminum woofer and midrange/tweeter combo.

• Check: Natural
  This mode averages out the frequency response of all speakers so that higher frequencies are less emphasized. This setting is only recommended if the Flat setting (or EQ off) seems too subjectively bright for your tastes.

• Check: Flat
  If your home theater system is comprised of similar quality speakers, ten this setting will average the frequency response of all speakers. While it sounds like the system is bringing all the speakers into alignment, the gist here is that YPAO is attempting to resolve to a flat frequency response each speaker in the room.

• Check: Front
  If your main speakers are of significantly better quality than the rest of the system this setting will attempt to adjust the frequency response of the other speakers to more closely blend in with the front channels.

Now let's take a look at how the YPAO system measures in Reference System from the listening position:

What you can see happening with the Flat mode is the YPAO system attempting to do some correction at the high frequencies as well as bump up the 350-400Hz range. As I mentioned, the result was pleasing and I noticed no significant decrease in soundstage or imaging.

The Natural mode, as indicated here, rolls off a bit more of the high frequency information starting from 2kHz, though gently, in order to perhaps compensate for brighter systems (or rooms). While I don't personally find this mode useful in my listening room, it would probably be much better than using a tone control to tame a bright listening room.

It's hard to tell the whole story with a single microphone at the listening position, but this should give a fairly accurate picture of what YPAO is doing in terms of its effects on your main speakers. The measurements required to tell you how it affects the entire system would be nearly insurmountable and better left to subjective listening evaluations.

Our prior review of the RX-V2400 detailed some subjective tests for that model and the evaluation of this unit agrees with our previous assessment. This receiver is clear and powerful. Even when feeding it analogue 5.1 sources from the Denon DVD-3910, the noise floor on this unit was extremely low. For a receiver at this price point to be able to drive a pair of 4-ohm, 88dB sensitivity reference speakers tells you something about the quality that goes into Yamaha products.

The solid bass lines of Track 12 really exercised the system in general and I couldn't help but crank up the music until the Yamaha was pushing over 95dB at the listening position. After a while I stopped and noticed the automatic fan mode had engaged. I felt the top of the unit and noted that it was warm, but not hot, to the touch. While not surprising at all, just be sure to have some ventilation around the top and rear of the unit as you would with any high performance amplifier. Keep in mind also that larger rooms demand higher continuous power output levels to achieve the same listening levels of a smaller room, so if you plan on cranking this receiver to insane levels for long periods of time in a large room, you may want to consider supplementing your system with a robust dedicated amplifier.

I next turned up Track 7 "I Can't Tell You Why" of the Eagles: Hell Freezes Over DTS DVD. Vocals sounded natural and uncompressed and the drums had a very smooth sound that arrived at the listening position unimpeded, as I expected. There were no surprises as I moved on to Track 13 "Life in the Fast Lane" and listened to Don Henley's lead vocals rough their way through the song while Joe Walsh creatively nursed his guitar to speak. Overall, multi-channel music sounded natural and convincing even at high SPLs.

Two-Channel
I listened to a host of my favorite 2-channel selections, including James Taylor's Greatest Hits and some relative unknowns such as Laura Story's Indescribable , which has become one of my recent favorites. Add to these selections tracks from Steely Dan, Seal and Toto and you have a well-rounded suite of listening material.

Using Yamaha's Pure Direct mode I was able to really experience what the RX-V2500's amplifiers were capable of putting out. Pure Direct puts the unit in 2-channel bypass mode with no sub output. With my main speakers set to Large the Yamaha's amp was working hard, driving full range frequencies to both of my 4-ohm RBH 1266-LSE mains. This receiver can play loud and was able to accurately reproduce bass transients in a way that was remarkable for a receiver priced just over $1000. The overall sound was capable of being precise and detailed while still retaining the ability to power through demanding material.

I wanted to give the Yamaha RX-V2500 amplifiers a thorough workout by driving all of its channels at fairly high SPLs. Placing a few select DVDs into the DVD player, I sat back to watch some high-impact movie scenes. Remember that for these tests, the Yamaha had configured all of my speakers to "Large", including the surrounds, so the amplifier was sending full range signal to all the speakers, including the low frequency information. The only sound going to the subwoofer was the dedicated LFE track. I engaged the Presence Channels and turned off the EQ for these tests as well.

In addition to playing my all-time favorite film, The Fifth Element, I popped in the newly-released Star Wars Episode IV: A New Hope to see how it sounded coming through the Yamaha. I wasn't disappointed. When explosions and laser fire weren't arcing through the speakers, John Williams' score was certain to be bellowing through on all sides. These movies do a great job at surrounding the listener and really pulling you into the action. With Yamaha's presence channels activated, the experience was, quite literally, lifted onto the big screen as we watched the films on a 100" diagonal Stewart Filmscreen Studiotek 130 powered by Yamaha's LPX-510 LCD projector. Turn on one of the 70mm Cinema DSP modes and you may never again watch a movie in your home without Yamaha DSP!

For some additional explosive action, I continued my listening sessions with Farscape: The Complete Third Season . Farscape is, in my opinion, one of the greatest series ever to arrive on television. The quality of the show is equaled by the soundtrack and score which came through with flying colors, at times audibly transforming my listening room into the living ship that is one of the primary Farscape sets.

Back when I had my RX-V3000, I would use some of the attack scenes in Pearl Harbor to demonstrate what the Presence Channels and Yamaha's Cinema DSP could do. I felt it appropriate to review the same scenes with the RX-V2500 to see how they fared and if my experience was as dramatic as it had been with the older receiver. I was not disappointed. In fact, I was again blown away by the stark contrast between standard 5.1 content and a 5.1+2 mix with Cinema DSP. For those utilizing a front projection system, Cinema DSP simply makes the movie going experience more epic with a wider soundstage and a great illusion of being part of the action. In addition, for those of you with an elevated screen, you can utilize the RX-V2500's Dialogue Lift to place some of the center channel content into the presence channels. The result is dialogue and action that is more aligned with the projector screen (rather than below it). When utilizing Dialogue Lift I actually preferred to engage the YPAO EQ into "Front" mode so that the Presence channels were EQ'ed to more closely match the timbre of my main speakers.

For movies I consistently found the General Cinema DSP mode to enhance the presentation without becoming distracting or artificially corrupting the surround track.

Editorial Note: Presence Channels
The Yamaha RX-V2500 allows you to select either Presence channels or Back Surround channels, not both. Even if you have an external amp, there is no facility for providing preamp outputs to both Presence and Back Surrounds at the same time. It would be great to see Yamaha to allow for both (even if one set is not amplified) in future iterations of this model.

With that, lets all first remember that receivers in the $1k price range from the leading companies today are an absolute bargain regarding their processing power, features, and performance. I like to think of them as an excellent Preamp/Processor (usually rivaling many costlier Pre/Pros) with a free amp thrown in. Whether the amp section within the said receiver is "good enough" depends on the following variables:

• Loudspeaker Impedance
• Loudspeaker Efficiency
• Room Size
• Room Acoustics
• Listening Preferences
• Whether or not you apply bass management to your Loudspeakers and utilize a dedicated powered subwoofer(s).

As you can see, there are a number of variables and the answer is simply not that straight forward. Let's continue on and establish some of the critical test criteria for gauging amplifier performance.

THD and IMD Distortion - This is a measure of how well an amplifier can faithfully reproduce a signal without introducing any artifacts or harmonics. While this is an important metric to consider, most solid state amps these days boast pretty low figures here (usually well below audibility) and are rarely a real world problem for well designed amplifiers.

Signal to Noise Ratio - This is a measurement of importance to consider as it is a ratio of the magnitude of the signal and background noise. Many amplifier manufacturers publish their SNR figures at full power, which can be misleading and hard to compare between different amplifiers at differently rated power levels. Many also apply weighing filters to yield better results such as dBa or dBc. This can make over a 10dB difference compared to unweighted measurements and should be noted when comparing various amplifiers. It is best to look at 1 watt levels (where the amp spends most of its time) and interpolate the SNR at the amplifiers full rated power. We will leave this topic for another article in the near future.

Frequency Response - This is a measure of how well an amplifier will reproduce a signal without attenuation or boosting with ideal being flat within the range of human hearing 20Hz to 20kHz +/- 0dB. This again is rarely a problem with well designed amps and there should be little reason why an amplifier cannot maintain at least +-.5dB from 20Hz to 20kHz. Some amps do result in excessive power fall off at high frequency due to slew rate induced distortion and this is something to watch out for. Thus why we check frequency response at 1 watt and full power for our amplifier testing.

Amplifier Output Impedance - This again is an important metric as it determines the amount of interaction or frequency response variation an amplifier may produce when driven by a reactive loudspeaker load. Usually lower is better, but some do prefer high output impedance tube amps for example since they can excessively roll off high frequency response and result in a warm sound. Note, sonically preferring something doesn't necessarily mean its more accurate or precise.

Damping Factor - This specification is somewhat overstated by most manufacturers and the reader is encouraged to reference our article: Damping Factor - Effects on System Response for more information. I still like to check for this as it is a good indication of amplifier output impedance and power supply capability. However, in real world scenarios, cable impedance usually nullifies the benefits of a very high damping factor and thus beyond a certain value as stipulated in the aforementioned article it becomes mostly academic.

Required Test Equipment

• Non inductive Resistors (8 ohms, 4 ohms)
• Oscilloscope
• Short 10AWG Speaker Cables
• Function Generator

Measuring Output Impedance and Power of Amplifiers

Step 1: Adjust the function generator until you read 2.82Vrms on the Unloaded amplifier as depicted in the left figure above. Record these results in Table 1. under 'Vopen' over the entire frequency range.

Step 2: Attach a non inductive Load to the amplifier and re-measure the output voltage over frequency and record the data in the appropriate 舠 Vload 舡 column specific to the load impedance used in this test in the three Tables below. Do NOT vary amplitude of the function generator, only Frequency.

Step 3: Calculate the amplifier output impedance (Zo) with the following relationship.

and

Step 4 : Plot the data from the Tables into Figures in excel.

Step 5 : Find the maximum unclipped voltage the amplifier can provide into the specified test load.

Step 6: Record the voltage over the specified frequency range.

Step 7: Detach the test load and record the voltage 'Vopen' vs frequency repeating step 3 to calculate output impedance.

Note: The following variables limit the absolute accuracy of this test method:

• Cable impedance and stray inductance in resistor
• Variance in line voltage (since all tests are done without a line stabilizer)

However, this is more of a real world than typical ideal test condition, thus for all intents and purposes serves well for this application.

Test Notes:

• The 8ohm test load + test cable measured: Rdc = 8.04 ohms ; Ls = 5uH (1kHz)
• The 4 ohm test load + test cable measured: Rdc = 4.03 ohms ; Ls = 3.8uH (1kHz)
• All measurements were done in 'Pure Direct Mode'
• Line Voltage was NOT held constant and varied between 117-119VAC
• All tests were conducted on the main channels of the RX-V2500
• All tests were conducted using EXT Multi-CH Inputs and Outputs when appropriate

Line Level, 8-ohm Load (RL=10kohm)

Full Power, 4-ohm Load

The fact that all keys are now backlit (activated via a button on the left side of the remote) would be cause for small celebration except that the remote stopped just short of the first down and opted to include "sea foam" colored labels on many of the primary buttons - rendering them nearly invisible in the dark, even when backlit. One other thing to note is that the numeric keys (which are not arranged in the familiar 4 rows of 3 format) are also poorly and unevenly backlit. It's a crime. Perhaps all of the manufacturers are finally catching on to the fact that many remotes may be used in the dark, though apparently RX-V1500 owners will not be as fortunate to receive a fully backlit remote. I say light the remote hard , and light it up blue with low power, high-performance LEDs. If you're going to light it, make sure all the buttons are visible and that you can use the remote to summon for help in the event that you are lost at sea.

Programming the remote is simple. The only difficulty I had was that the programming buttons were somewhat good at eluding the tip of my ballpoint pen. Often times it would take me 4-5 tries to lock in a learned device. A paperclip may render this comment moot.

I also like the feel of the buttons themselves. The no-slip texture is easy on the hands and helps ensure you select the right buttons. Users of previous Yamaha remotes will need to get used to flipping the new AMP/SOURCE/TV switch which is a nice development that instantly directs remote control commands between the receiver, currently selected source, or television (as programmed into the DTV source.)

Separate power buttons for the receiver, source and television help ensure that you'll never mistakenly turn off the wrong device.

Certainly the Yamaha RX-V2500 is not the year's greatest achievement - I mean, it's not like they launched a commercial spaceship into orbit, right? It is, however, quite possibly the most amazing receiver you will find for just over $1000. With a fairly accurate YPAO system and room corrective EQ that doesn't sound half bad, this is a receiver to be reckoned with - and you can bet other manufacturers are watching. Yamaha has consistently provided improvements to its lineups over the years, but since 2003 they have been on a mission - and technological progress and excellence appears to be their goal. As we concern ourselves more and more with room acoustics and technology that makes it easy to setup and manage our home theater systems, products that incorporate technologies like Yamaha's GUI and YPAO systems are imperative. And what's more, they are going to be expected. We're happy that there are a few leading companies out there bringing these technologies home and daring the market as a whole to keep up.