AVP-A1HDCI Measurements and Analysis
Frequency Response & Distortion
Denon AVP-A1HDCI Preamp Frequency Response
I measured a ruler flat frequency response with a -3dB point around 200kHz in all 2CH stereo modes (ie. Pure direct, Stereo direct). The AVR-5308CI measured similar bandwidth as well.
Denon AVP-A1HDCI Preamp FFT Distortion Analysis
With 200mVin, I set the master volume until I reached 1Vrms out of the preamp. The FFT plot was so clean that I couldn’t measure any appreciable distortion products until I ramped up the signal level to drive the output to nearly 6Vrms. At that point, I measured (15.268+ 80.424)dBv = 95.69dB or 100*alog^-1(-95.69/20) = .0002% THD + N which is among the lowest distortion I’ve ever measured in a preamp regardless of price. The AVR-5308CI didn’t compete here as the measurable harmonics were about 6dB worse driving an output of 1Vrms than they were on the AVP-A1HDCI outputting nearly 6Vrms.
I measured about 15.5dB of gain via the balanced and unbalanced outputs of the AVP-A1HDCI preamp (with source level set to 0dB on the particular input and channel trims set to 0dB). The preamp has plenty of output capability as evident by the following measurements all taken @ < 0.1% THD +N:
Balanced:
- Vmax out = 14Vrms
- Vmax In = 15.5Vrms
Ubalanced:
- Vmax out = 7.2V (3.8Vrms was the limit on the AVR-5308CI)
- Vmax in = 8V
Though this is more than enough output to drive any power amplifier to maximum capability (THX amps require about 2Vrms to reach full power) the gain is structured a bit low requiring the input signal to be larger than normal to reach high output levels. This explains why I always had to peg the volume near max on low compression sources. I personally wished Denon would have followed a more common gain structure in this processor like I’ve seen on other A/V products as follows:
- Unbalanced: Av = 17dB
- Balanced: AV = 23dB (6 dB higher than unbalanced)
SNR
With 200mVin and 1Vout, SNR = 95dB (unweighted) in pure direct mode. This is an excellent measurement, and with its ample drive capability proves the AVP-A1HDCI is a top notch preamplifier that will satisfy even the most critical audiophile.
Crosstalk
Denon AVP-A1HDCI Crosstalk Measurement at Full Rated Power vs Frequency
Running a full range frequency sweep from the preamp, it displayed superb crosstalk measurements between the front left and right channels of over 108dB @ 1kHz with a slight rise with increasing frequency due to capacitive coupling and actually no increase at low frequencies indicating no magnetic coupling was present. The separated power supplies Denon boasts in this design truly show off their benefit via this measurement as evident when I measured about 20dB worse crosstalk on the AVR-5308CI under similar test conditions. I did note that when I engaged the bass management circuitry, the crosstalk measurement level went up about 10dB which is likely because of the added trace paths and associated circuitry but at these low levels it’s more academic than a concern of audibility.
Measurement Wrap Up
Every measurement I made of the AVP-A1HDCI was benchmark. This processor has one of the cleanest preamp sections I've seen and certainly has a top notch DAC section that few products regardless of price can compete with. Whether you're listening to redbook CD's, DVD-A, SACD or the latest hidef formats such as Dolby TrueHD and DTS HD, you can be assured that the AVP-A1HDCI will process those formats with the highest resolution possible.
Recent Forum Posts:
There is no way a manufacturer can dictate the SPL you will measure in your room with your speakers when you engage the test tones. You can adjust the master volume while the test tones are engaged and set it so all of your speakers read 75dB at your seated area. Then record that level and use that as your reference if you like.
Perhaps this is unique to Onkyo/Integra but the test tones are available in the Setup menu and when I enter the Setup menu the MV (master volume) level setting is irrelevant, in fact the MV level cannot be adjusted until you leave the Setup menu. The test tones are in the Channel Level menu under speaker setup and are designed to produce approx 75 db in room. The individual channel level adjustments can compensate for speaker, room and distance anomalies and allow you to get to the 75db tone level on all speakers. Once this is done, then reference level is @ 0 MV.
This thread is the wrong place for this discussion and I apologize for the OT.
Regarding calibration, the Speaker Setup Test Tones emitted by my processor are not governed by the MV of the processor . I'm sure is the case with the Denon and most if not all other AVR's/SSP's. If you are using an external source for test tones then MV might apply. My manual says the Integra Test Tones are output at 75 db. After Audyssey calibration, my main channels are running at 80db with the channel levels @ approx -9db for the LCR's. I agree with your assumption that this is due to the high sensitivity of my speaker as I previously stated.
Since speaker sensitivity levels are highly variable, perhaps the manufacturers should allow the user to input the manufacturers’ sensitivity numbers into the speaker setup and then calibrate the test tones accordingly. Of course, that would depend on consistent (and honest) numbers from the manufacturers.
There is no way a manufacturer can dictate the SPL you will measure in your room with your speakers when you engage the test tones. You can adjust the master volume while the test tones are engaged and set it so all of your speakers read 75dB at your seated area. Then record that level and use that as your reference if you like.
I can also exceed reference levels in my 6000 cu^ft room with Audyssey and PLIIx engaged but its a bit of a challenge when playing back certain HD DVD discs and CDs that are recorded at low levels.
I've already spoken to several manufacturers whom are working on this issue and addressing it with next generation volume controls that will allow more dynamic headroom and better scaling. If this wasn't an issue like I mentioned then nobody would be addressing it.
gene;683833
You're still missing the point. The Volume scaling issue I mentioned exists on virtually all products using Audyssey, THX, PLIIx, etc. It drops the max available volume level when all processes are engaged. The Integra simply doesn't show the limitation it just limits max volume while still allowing you to increase it. In most circumstances this wont be noticed unless you are listening to sources recorded at very low levels like I mentioned in my review. It also depends on the efficiency of your speakers, the size of the room and the levels you prefer to listen at.
Regarding your calibration issue:
If I understand your problem correctly, when you hit the "test tone" button the SPL you measure is 80dB instead of 75dB for each speaker. If that is the case its likely b/c the high sensitivity of your speakers. The simple solution after you balance out all of your channels is to lower the master volume until you read 75dB for all of your speakers then note the master volume level so you can set it to that when playing back movies.
Thank you for the reply. Perhaps I am "missing the point" but the fact remains that I can increase the MV of my system and see the resultant increase in SPL on the meter well beyond reference levels. If Audyssey is limiting the max volume it is of no consequence to me.
Regarding calibration, the Speaker Setup Test Tones emitted by my processor are not governed by the MV of the processor . I'm sure is the case with the Denon and most if not all other AVR's/SSP's. If you are using an external source for test tones then MV might apply. My manual says the Integra Test Tones are output at 75 db. After Audyssey calibration, my main channels are running at 80db with the channel levels @ approx -9db for the LCR's. I agree with your assumption that this is due to the high sensitivity of my speaker as I previously stated.
Since speaker sensitivity levels are highly variable, perhaps the manufacturers should allow the user to input the manufacturers’ sensitivity numbers into the speaker setup and then calibrate the test tones accordingly. Of course, that would depend on consistent (and honest) numbers from the manufacturers.
I was referenced to this thread from another Forum. I found the section on Audyssey and specifically, the "Volume Scaling Issue" interesting. I have the opposite problem. My Integra DHC-80.1 test tones register approx 80db on an SLP meter with or without Audyssey engaged and I cannot apply sufficient cuts to the LCR levels to reach 75db on the test tones. I have both digital and analog SPL meters and both give approx the same results. I end up using 80db as my test tone level thereby making -5MV on my Integra actual reference level.
The only relevance here is that apparently Audyssey does not limit headroom with my Integra processor. Unlike Audioholics experience with the Denon, my system will produce SPL well beyond what my room (and my ears) can handle. It is just interesting to me that the Integra test tones play at 80db rather than the 75db mentioned in the Integra User Manual. I attribute this to the 101db efficiency of my JRT T12HT's. I have had conversations with both Integra and Audyssey and neither has an explanation for my test tone SPL irregularity.
You're still missing the point. The Volume scaling issue I mentioned exists on virtually all products using Audyssey, THX, PLIIx, etc. It drops the max available volume level when all processes are engaged. The Integra simply doesn't show the limitation it just limits max volume while still allowing you to increase it. In most circumstances this wont be noticed unless you are listening to sources recorded at very low levels like I mentioned in my review. It also depends on the efficiency of your speakers, the size of the room and the levels you prefer to listen at.
Regarding your calibration issue:
If I understand your problem correctly, when you hit the "test tone" button the SPL you measure is 80dB instead of 75dB for each speaker. If that is the case its likely b/c the high sensitivity of your speakers. The simple solution after you balance out all of your channels is to lower the master volume until you read 75dB for all of your speakers then note the master volume level so you can set it to that when playing back movies.
Or will that even be possible?
