TonyD'Amore Posted March 17, 2016 Report Share Posted March 17, 2016 What point are you needing to prove Just wanting to show this unit distorts at 22 and show what the actual % of distortion is, thats all... Im a nobody, you're the somebody... LOL Bring it by, we will put it on the DD-1 and a HP8903A Link to comment Share on other sites More sharing options...
headshothills Posted March 17, 2016 Author Report Share Posted March 17, 2016 What point are you needing to prove Just wanting to show this unit distorts at 22 and show what the actual % of distortion is, thats all... Im a nobody, you're the somebody... LOL Bring it by, we will put it on the DD-1 and a HP8901 Ohh Snap... Will do!! 2018 F350 Platinum Hostile w/ Toyo 37 MT's Big 3 Gately Audio 4 - 8" Enclosure B2 Audio XM8's SounDigital Evo 5000.1 2ohm SounDigital Evo 1200.4 4ohm AudioControl DM-608 PAC AmpPro - Optical Out Kleinn Demon Train Horn Viper DS4+ Smart Start Link to comment Share on other sites More sharing options...
TonyD'Amore Posted March 17, 2016 Report Share Posted March 17, 2016 Admittedly I haven't tested this particular Alpine unit, yet. Sounds like I will in a bit. BUT, I have tested other Alpine heads, and other brands as well that have this problem. Just because you cannot see it on your "scope" doesn't mean it isn't there. There is a video of ours on YouTube where we test a high end alpine that has distortion at low or high volume levels, over 2%! And guess what? YOU CAN'T SEE IT ON A SCOPE. It's not *noise* either. If Alpine or the other companies that are having this problem with their headunits wants to hire me to consult to fix the problem I am available for that. I have already fixed it on Boss headunits about 5 years ago. NO I won't TELL you what the problem is, without billing you. Tony Link to comment Share on other sites More sharing options...
Audioguy564 Posted March 17, 2016 Report Share Posted March 17, 2016 Juan Rodriguez Chief Technology Officer D'Amore Engineering T15KW Support Engineer System. KVT512 Kenwood Fold Out Monitor Epic-160 Audio control Indash epicenter (1)T1500-1BD with T2000.1 Transformer 1700 watts at 2 ohms (2) T600-2 with T800-2 Transformers 320/ch at 4 ohms (2) QSD216 Q series MB Quart 6.5 inch components (3) P3D212 Rockford P3 12inch Subs (1) Very Loud Altima Coupe! Link to comment Share on other sites More sharing options...
TonyD'Amore Posted March 17, 2016 Report Share Posted March 17, 2016 Link to comment Share on other sites More sharing options...
bcbrassard Posted March 17, 2016 Report Share Posted March 17, 2016 Hell Ya.... that video tells all IMO. Link to comment Share on other sites More sharing options...
baron_of_bass Posted March 17, 2016 Report Share Posted March 17, 2016 **************************************************************************************** Class in session. Have a seat. *************************************************************************************** The DD-1 detects harmonic distortion. It measures it, by comparing the quantity of it to the original signal. Once the harmonic distortion reaches -40dB of the original signal the DISTORTION LED is illuminated. Because 20 * LOG ( 0.01) = -40dB 0.01 = 1% . The amplifiers that have trouble being tuned on the DD-1 have either a harmonic distortion measured by the bandpass filters set for 3rd harmonic or the just happen to have *noise* at those exact frequencies. Does it matter which? Not at all. I don't want any noise at 120Hz or 3kHz. Anything that is not the original signal is a DISTORTION of the original signal, albeit not harmonic. You saying that you can play pink noise and witness the Distortion LED illuminate removes all doubt that you have no idea how the tool works or what pink noise is. Pink noise contains all frequencies, including those frequencies that we are looking for, thus the LED will blink. Same thing if you use music. The tool isn't designed to work that way. Pink noise is not able to be analyzed for distortion as there is no reference, pink noise is random by design. All of your assumptions are that the DD-1 was designed as a THD+N analyzer. Did you google that or something? That is not how the DD-1 works. THD+N analyzers work by removing the test signal from the received signal via a bandpass filter subtraction and calling the remainder TOTAL HARMONIC DISTORTION + NOISE. Not how the DD-1 works at all, quite the opposite. About building one for $10. Good luck. Tony D'Amore PS "FACTUAL STATEMENT" This guy doesn't understand what he is saying, at all. The DD-1 is NOT a distortion meter. It does not measure anything. The DD-1's main limitation is that it cannot discern between noise and distortion. It is important for people to understand what the tool can and cannot do. There are many issues with the DD-1 and certain amplifiers - which are the likely result of unexpected harmonics or noise. That does not directly translate to 1% THD. Anyone can prove this to themselves by playing a pink noise track. You will see the distortion indicator illuminate very early. This is not because there is 1% THD in the signal, but instead the DD-1 is confused by what it sees. If it was appropriately named the UFD-1, for Unexpected Frequency Detector, it would be more honest. You could also say that sometimes, the unexpected frequencies may correlate with distortion. You can say that under some circumstances, the DD-1 will illuminate with 1% THD on a 1kHz sine wave. But the disclaimer should be added that illumination doesn't guarantee there is 1% distortion in the signal and that noise can provide a false positive. I had my local dealer put a BNIB Alpine CDE-HD149BT on their DD-1 and they did NOT measure distortion with a 1kHz tone up to full volume. Pink noise resulted in detector illumination around half volume, which proves my points above. The OP has be struggling with his DD-1 measuring head units with what appears to be false positives. The main issue with analog electronics is the accuracy of the components and the tolerances of the components. Those are factual statements. My personal opinion is as follows; If the DD-1 has more than $10 in internal parts, your designer isn't very clever. These days, with microprocessors so cheap, you can have a more useful detector, with a wider range of input signals and usable output information... for the same price point. I feel the price of the DD-1 is greedy because it is a HUGE markup for a simple circuit with a branded sticker. We won't agree on my opinions, that's ok. Cheers. Game. Set. Match Team Bass-Hz Link to comment Share on other sites More sharing options...
headshothills Posted March 17, 2016 Author Report Share Posted March 17, 2016 Admittedly I haven't tested this particular Alpine unit, yet. Sounds like I will in a bit. BUT, I have tested other Alpine heads, and other brands as well that have this problem. Just because you cannot see it on your "scope" doesn't mean it isn't there. There is a video of ours on YouTube where we test a high end alpine that has distortion at low or high volume levels, over 2%! And guess what? YOU CAN'T SEE IT ON A SCOPE. It's not *noise* either. If Alpine or the other companies that are having this problem with their headunits wants to hire me to consult to fix the problem I am available for that. I have already fixed it on Boss headunits about 5 years ago. NO I won't TELL you what the problem is, without billing you. Tony So really what you're saying is... Go buy a Boss headunit!! LMAO 2018 F350 Platinum Hostile w/ Toyo 37 MT's Big 3 Gately Audio 4 - 8" Enclosure B2 Audio XM8's SounDigital Evo 5000.1 2ohm SounDigital Evo 1200.4 4ohm AudioControl DM-608 PAC AmpPro - Optical Out Kleinn Demon Train Horn Viper DS4+ Smart Start Link to comment Share on other sites More sharing options...
ethan_leonardo Posted March 17, 2016 Report Share Posted March 17, 2016 **************************************************************************************** Class in session. Have a seat. *************************************************************************************** LMAO Link to comment Share on other sites More sharing options...
ethan_leonardo Posted March 17, 2016 Report Share Posted March 17, 2016 Admittedly I haven't tested this particular Alpine unit, yet. Sounds like I will in a bit. BUT, I have tested other Alpine heads, and other brands as well that have this problem. Just because you cannot see it on your "scope" doesn't mean it isn't there. There is a video of ours on YouTube where we test a high end alpine that has distortion at low or high volume levels, over 2%! And guess what? YOU CAN'T SEE IT ON A SCOPE. It's not *noise* either. If Alpine or the other companies that are having this problem with their headunits wants to hire me to consult to fix the problem I am available for that. I have already fixed it on Boss headunits about 5 years ago. NO I won't TELL you what the problem is, without billing you. Tony So really what you're saying is... Go buy a Boss headunit!! LMAO Maybe you should just get one of those Bluetooth speakers and set it on your dash. Very simple to use and setup, and no need to test for distortion. Link to comment Share on other sites More sharing options...
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