I have had mine in my car for 21 years now. I’m using old school Infinity 3 ways and the sound is so clean. It’s a great amp!

its been interesting following your testing

Amazing video ‼️

Buy an alpine 3558. When you test and hear that amp you will be extremely happy! I recently bought a non working Alpine 3558. One side had a blown power supply caused by a shorted BJT. The 2sa1637. I installed Irfz44n in the power supply and replaced the 2sa1637 on channel 4 with a 2Sa1386A. I also removed the NPN on that channel and replaced it with a 2sc3519A. Put it back together and nothing. Completely dead!!! No lights, nada. Figured out all the small 10v and 16v Elna caps leaked and ate away some trace. Repaired trace and replaced with nichicon caps. Now 2 orange lights. Figured out Q509 on SD circuit was bad. Replaced transistor and 2 green lights and relays engaged. After listening to this amp I am seriously amazed. Songs sound completely different now. Much better. However the amp gets pretty warm even at low volumes. Got a higher cfm fan installed and it stays cool all the time. Just a hint of warmth on the heat sink after listening for 8-10 hours and mid volume. I believe the first 9w is class A on 4 channels. Above that it switches to class AB. I decided to keep this amp. So, I bought all new nichicon and chemi-con caps to replace the 30+ year old caps before they try to eat the board. Also, channel 4, the one with new BJTs sounds the same as the others but seems to be slightly more powerful on moving speakers. Will probably replace all output BJTs when I put her back on the bench. It’s a truly great sounding amp. I have many vintage Phoenix gold, Soundstream, Sony, clarion and PPI amps. My favorite 4 channel amps would be a Toshiba 873, crossfire ca404, PPI a304, Phoenix gold sapphire 1.4x, Phoenix gold m44 and clarion pro audio apa4160. Can’t leave out my audio art 200.2rxt, AA 100HC (subwoofer amp) and infinity kappa 255a.

I’ve used both class ab and class d amps on my tweets and mids and I much prefer class ab. I used JL HD600 for years and decided to repurpose it for midbass duty. I then ran alpine A70F for a while and I wasn’t pleased with it. Both amps had plenty of power but sounded thin and lifeless.I then switched over to an old school mtx 4320 I’ve had since the early 90’s. It’s from the era when they were still made in Arizona. It’s like my front stage took on a whole different sound. The sound was just more full and not brittle sounding like the class d I’ve tried. The best way I can put it is that it just had more life and not sterile. Maybe it has something to do with that second harmonic that you describe as being warm….idk. Maybe it’s just some psychoacoustic trick it’s playing on my ears. Again idk why they sound different to me, they just do. I would still have the mtx in my system if not for the fact that it picks up some alternator whine. I replaced it with Mosconi pro 4/10, which is class ab and I’m very satisfied….for now.

@n.shiina8798

8 ай бұрын

there is plenty things that can make ones liked or disliked the sound. two amp with exactly same second harmonic content , same THD+N number, will sound different if the harmonics pattern is different. like, one amp have 2nd at -60, 3rd at -80, 4th at -70, 5th at -90 vs one that have 2nd at -60, 3rd have -70, 4th at -80, 5th at -90. translating human perception into numbers is difficult at least for me

Surprising result again :D Have you thought about building some 2 way speaker cabinets so you can bench these amps without having to install them in your car?

I thought I was happy before I watched this video.

I'd like to see a test of my Pioneer PRS-A900. Some of these older ab amps are perfect for mids and tweeters and can be found cheap.

consistency between channel is mostly came from component matching. im kinda surprised this old AB actually came up really close to each other

I'm of the opinion that there's some vague minimum threshold of distortion that each person considers "good". All amps above this level are basically equally good (as far as distortion is concerned). So if you have two amps and they both sound great, I don't see the need to choose the one with lower distortion based on principle and theory. If your not able to hear the difference, does it matter? Then you have other specs like signal to noise ratio. Are you able to test that? I always felt it was decently important. Too bad manufacturers rarely list it at 1w.

Cool video. I just hope people don't take it too seriously and sell their new amps to buy really old amps. 😂

I am buying that exact same amp (MRP-F240 )tomorrow for my tweeters.