Hi, folks! This is the first time I post, so I guess I'm a newbie with a problem; I have an Alpine Flex356 feeded by a Blaupunkt Daytona MP3. The front speakers are from Lanzar, the rear from Proaudio (6" * 9"). The prob is when I connect the rear ones, the amp runs so hot (green led still on), it cuts out after 10 minutes on a sunny day (I live in Portugal), but I don't wanna throw them away, 'cause they sound so good specially in the bass, I don't need a sub.!!! Seems to me that the speakers go so deep in the bass section, it makes the impedance fall and therefore overheat the amp! On the other hand, the amp has such good sound I'll miss it! Any sugestions? Thanks in advance!
How come? It can be wired to provide 2,3,4, or 5 channels, but I never used the sub output!? Plus, right now I'm using the front speakers (Lanzar) in the 2-channels-bridged mode, and it don't even get warm... Is it possible that the rear speakers's coil are made of a to-thick wire to get the impedance too low on the bass section? TIA
How come? It can be wired to provide 2,3,4, or 5 channels, but I never used the sub output!? Plus, right now I'm using the front speakers (Lanzar) in the 2-channels-bridged mode, and it don't even get warm... Is it possible that the rear speakers's coil are made of a to-thick wire to get the impedance too low on the bass section? TIA
Ok, first I have to thank you for your reply! But I replaced all the terminals at output and speakers (soldered) connections, checked all the wiring several times, don't have a sub and I even replaced the ground cable (trunk floor), by one straight to the battery negative contact... but no results, I still burned my hand, literally! TIA
By the way, another question: if I don't get to cohabitate the Proaudio and the Alpine, will I be able to connect in parallel both speakers to the sub output? By the manual, I can't tell if this output (100W) would handle 2 ohm... TIA
if the channel is bridged, it only takes 4 ohms. if its not a bridged output then 2 ohms is fine the amp may just be in a bad location. older class AB high power amps get very hot anyway.
TKS! But shouldn't the sub output be able to handle 2 ohm, since it's not bridgeable? And if when they were connected to the rear outputs (which SHOULD handle 2 ohms), they were overheating the amp, what will happen if I parallel them? TIA
if its a mono channel then yeas 2 ohms is fine, even if that means two 4 ohm subs in parallel. just be aware the larger speakers (ie, subs) will make the amp work harder, and get hotter.
Thanks! Is there a way to check if the speakers impedance's dropping too low? I know my way around digital multimeters, but don't have no oscilloscope and stuff... TIA
Ok, I think I just found the prob. It seems to be on the 5th channel (sub), which is somehow connected to the rear channels... As soon as I plugged both rear speakers (Proaudio 6"*9"), it started heating fast, cutting in and out the outputs. Then I removed one of them to get 4 ohms, started working hot but no cuts, with very weak bass (gain at max), even weaker than in the front ones, which in turn had the "HP FILTER" on at 80Hz. So, What seems to be happening is the sub/rear outputs are degraded and need fix, maybe due to water ingress I had a few years ago on the room the amp was stored (for 6 years, in the box)! Would you agree? See schemes. TIA
Damn! I bought it 5-6 years ago, waiting for the chance to mount it and now I have to throw it away... ! Well I think I'll open it to see what I can do before giving up! The funny part is that the guys at Demestre (Alpine official in Portugal) had it for 3 days and couldn't find a fault! Could they be using a pure resistive load, such as a 100W-4ohm resistor? TIA!
