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Everything posted by TonyD'Amore

  1. If you want to send your to us we can reprogram it for you with v3.93 and send it back. What has happened with the AMM-1 is that it was originally intended for use with sinewave sweeps and music, it originally shipped with v3.8 firmware and all was well. After people started playing with the AMM-1 they started doing sine-wave burps. When these burps are done with a Class D amplifier it causes a nasty back EMF spike when the burp stops. The AMM-1 would read this nasty spike and calculate power and display it. So someone testing a 1000 watt amp could burp it and get a 10,000 watt kick back spike the AMM-1 would display 10,000 watts. So I started working on that problem and kept making engineering code revisions until it was solved, this was v4.0 firmware. So we started programming them with 4.0 in production. After people started getting them and using them they sometimes had trouble reading music with them. (it's pretty tough for the computer and code to tell the difference between music and a spike as music sometimes is just a bunch of spikes) So I started back tracking through my revisions until I found a version that reads music but can ignore spikes. You want 3.93 firmware. This is the best working firmware (can have spike problem on rare occasion) but works with music and shows impedance and power on the same display page.
  2. The sensitivity adjustment of the OM-1 should allow it to be used on amplifiers from 12V - 150VAC output. Is this a class D subwoofer amplifier that you are having the problem with?
  3. I know this is a very late reply and I apologize for that. As the info on this forum is permanent and searchable its good for the database so here we go.. Yes you would measure with the DD-1 probes ​across the bridge. Left positive and Right negative on most amplifiers. Yes the amplifier outputs (unloaded) will clip at the same point whether bridged or not. The bridge is just the two outputs channels running the same load instead of their own loads.
  4. I've tried Track 1 (40Hz 0db) Track 3 (40Hz -5db) and Track 5 (40Hz -10db). Wow if it won't clip with the 0dB track then it must have a anti-clipping circuit in it or some type of rollback circuit so that it can't be pushed too hard. I personally have not seen or played with one of these amps in person though I know that it is VERY similar to a model in the Hertz lineup and we have heard of people having trouble with that one as well. If the amplifier is not allowed to clip one may consider that an amplifier problem, not a DD-1 problem. The DD-1 is doing what it is supposed to do, alert the user of distortion over 1%. If the amp isn't capable of clipping it not work on the DD-1 or DD-1+. If you want to set it with a voltmeter like someone mentioned, you can do it, but you must use one of the overlap tracks. Simply using a 0dB sine and setting with a voltmeter or scope will result in ZERO gain overlap. As a side note for you number chasers, a 1000 watt amp that is allowed to clip will be significantly louder on the meter than a 1000 watt amp that is not capable of clipping. Based on the information you have presented to me here, and not playing with the amp in person, I'd say this amp has a rollback circuit of some type that doesn't allow for clipping. Tony
  5. If you can get 1.8V out of the RCAs with Track 1, how many Volts do you get out of the speaker terminals with 1.8V going into amplifier with gain at minimum? How many at Maximum gain? I'm guessing that the amplifier doesn't have enough gain designed into it. But with those measurements made we will know for sure. Tony Definitely not user error. I swap out the JAD1200.1D for my old hifonics amp and follow the same procedure (instructions that came with the dd1) and it works, distortion light shows up. With the JAD the distortion light never lights up. Guess I would have to make a video of it. RCA voltage is 1.8v at max clean volume. I can get it to distort while finding the hu max clean volume through the RCAs just not after I hook into the JAD1200.1D.
  6. All amplifiers should work on the DD-1. The blink while turning up the gain is caused by the DD-1's auto-range circuit shifting gears into the next range. The fact that the distortion LED doesn't illuminate even when the amplifier's gain control is all the way up would indicate the amplifier doesn't have enough gain designed into it. Amplifiers for automotive use should be able to reach clipping with 200mV of input and the gain control maxed. Tony
  7. Thank you guys for all the well wishes, I'm feeling better and haven't had any issues lately, thankfully! My heart went into A-fib the night of March 31 while I was asleep I guess? I woke up at about 4am to my 10 month old son crying and while helping the wife tend to him I noticed my heart felt like it was beating randomly. I asked her to feel my chest and she agreed. I went back to sleep until 7am and when I woke it was still doing it. I tried to take my blood pressure and the blood pres machine couldn't read me and just gave me errors. It always works so I knew something was up. I still drove myself to work though as I "felt" fine. After being at the office for about 30 minutes my partner Juan suggested that I go to the Urgent Care because it is nearby, nice, and you shouldn't "fuck around with that" - in his words. I drove myself there too. They got me in and did an EKG, told me I was in Arterial Fibrillation and my pulse was around 170 beats/min and that the Ambulance was coming for me. Now in the back of an ambulance headed to the ER the paramedic is explaining to me that my heart rate is now over 200 beats/min and I would probably end up having a rather bad day including passing out and having a date with the defibrillator. They started giving me injections of something that would make my heart slow down while on the bus ride, but it did nothing for me. Still at 200 bpm arriving to the ER. They starting doing lots of blood work, x-rays, sonagrams of my heart and administering different drugs to slow it. Long story short, 10 hours later my heart had returned to normal rhythm and pace. Then I had to spend the next 24 hours on different drugs and tests because I was at a high risk for a blood clot and stroke from being in A-fib for as long as I was. I'm on a med now to keep the heart chill, the reason all this went down is still unknown but my cardiologist says 75% chance its from sleep apnea. Did a sleep study a few weeks ago, get the results tomorrow. The class D hate will live on! Thanks guys! Tony D
  8. The general spec for Bluetooth is 10 meters (33 feet) We do some special things with ours to be able to surpass this. We typically see 50 - 60 feet in our office with walls and stuff, outside in the parking lot we see about 100 feet. This is streaming from a iPhone 6S+ in my hand.
  9. A two way passive crossover as an example separates the low frequency audio and the high frequency audio. It does so by placing magic resistors in line with the tweeters and with the woofers. The magic is that these resistors change resistance (impedance) with frequency. For the tweeter we use a magic resistor that gets higher in impedance as the frequency decreases. At 10kHz this resistor might be 0 ohms, at 5kHz it might be 1 ohms, and at 2.5kHz it might be 4 ohms and at 1.25kHz it is 12 ohms, at 612Hz it is 48 ohms; and so on. If we are using a 4 ohm tweeter and the magic resistor hits 4 ohms at 2.5kHz, this means only half of the power will be going to the tweeter at 2.5kHz vs when the magic resistor isn't active. This half power point is called the -3dB point or the crossover point. Also notice that as the frequency halves, the impedance of the magic resistor goes up by 4x. This indicates a 6dB per octave crossover. In a 12dB per octave crossover the magic resistor goes up by 16x per frequency half. The same thing happens with the woofer, but the magic resistors used for this work the other way. As frequency goes up by 2x, the impedance goes up by 4x. (6db per octave). So with our 2 way component set lets do an example of what happens with impedance vs freq. We will use a 2kHz crossover point and a 12dB per octave crossover for high and low pass. We will also use 4 ohm woofers and tweeters. We are going to ignore impedance rise of the drivers themselves for this example. This will demonstrate how a properly designed component set can maintain 4 ohms at any frequency even. Frequency Impedance of Woofer + magic R Impedance of Tweeter + magic R Parallel impedance (what amp sees) ---------------------------------------------------------------------------------------------------------------------------------------------------------------------- 31 Hz 4 ohms 12 Mohm 4 ohms 63 Hz 4 ohms 1 Mohm 4 ohms 125 Hz 4 ohms 84 kohms 4 ohms 250 Hz 4 ohms 6916 ohms 4 ohms 500 Hz 4 ohms 580 ohms 4 ohms 1 kHz 4.3 ohms 52 ohms 4 ohms 2 kHz 8 ohms 8 ohms 4 ohms 4 kHz 52 ohms 4.3 ohms 4 ohms 8 kHz 580 ohms 4 ohms 4 ohms 16 kHz 6916 ohms 4 ohms 4 ohms This magic resistor is made from capacitors and inductors; and sometimes resistors too. So as to how this relates to the AMM-1, it depends if you are trying to measure the actual power going to one of the speakers in the component set, or if you are trying to measure the amplifier output into the complete component set.
  10. RF HLC and HLC-4 will likely give you the same problems. The RF BLD should work well for you though. Here is the problem, the inexpensive LOCs use a transformer to take the high level signal and reduce it down to low level. Transformers work by creating a magnetic field and transmitting the signal that way. Like wireless communication. As you may be aware wireless transmission works best at high frequencies, at lower frequencies it basically stops working. That is what is wrong with all the inexpensive LOCs out there, they use transformers. It works fine at 1kHz, but below 50Hz the wheels start to fall off. At 40Hz they are so distorted the DD-1 will report distortion at any level. By 20Hz there is nothing that resembles a sine wave coming out of those things. The transformer coupled LOC is a great example of a product designed by a marketing person. No electrical engineer would ever recommend that.
  11. Our bottleneck with cooling was just the thermal interface material. Which may be more easily seen in our design since we have so much heatsink. At 25A per power supply MOSFET we were getting a delta of 40C between the MOSFET and the heatsink behind it with the best material we could find (berquist high flow 650P). With the Alumina we are at half that. We don't really have any hot spots, which I attribute to so much mass again. I don't know of a single mobile audio amplifier that has a 2" thick solid aluminum heatsink under the devices. So in our design the aluminum gradually and evenly heats up, the two fans in the back aren't blowing on anything. They are only to cause a pressure inside the amplifier so that air oozes out the gaps between the heatsinks and top cover. At a company I used to work for we would run 2 ohms full power sine for testing, it had to run at least 10 minutes like this to pass the test. In 10 minutes of that on this amp it is just getting warm enough to start turning the fans at the lowest speed. Our thermal design had to be this robust if it is to sit idle in Class A all day drawing 40A or more. That means that in Class A it is burning up over 500 Watts into pure heat into the heatsinks. We drove from Phoenix to Las Vegas like this, the amplifiers never got hotter than 140F.
  12. Rolling back meaning making less power as they get hot to protect themselves. I'm really not a fan of any class D. I don't see its usefulness unless it is a small battery operated device (ipod)
  13. About 1/2 of the small class D full range amps on the market today are just a chip amp with a power supply. A chip amp that rolls back like crazy when it gets hot. A chip amp who's design makes it very difficult to heatsink properly. Sound like a recipe for never making rated? Yep. http://www.digikey.com/product-detail/en/TAS5630DKDR/296-24624-1-ND/2091722
  14. Thanks Boz. Yeah we tried several types of the high flow material, 300, 600 and 2000. It is good, but not as good as the ceramic. Yes the ceramic has to be used with a very thin layer of thermal grease for those microscopic imperfections. Juan has all of those tools on his bench, anytime you see him using a burned up pos Hakko he is on my bench lol. The home amp isn't for sale, this model of the car amp has a MSRP of $4199. This is introductory and could change. There are 3 more models to follow with the same design.
  15. As far as the Kenwoods not making power.... yeahhhh. We have a few AD-1 owners who have reported the same thing on a few models.
  16. I'd be interested in a D'Amore explanation on this. A $400 tool not doing what it was intended to do should be a concern. The AMM-1 is dead on with the $3500 AD-1 Amp Dyno. Like others have said, what was the impedance on those runs mentioned above? Because "wired to 1 ohm" means nothing at all. It could be 15 ohms at the frequency that was used for testing, in which case a 2k amp would only put out a few hundred watts.
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