Garage sale score

ravaneli

I made a spontaneous purchase today. I accidentally saw this guy and offered 100 bucks to the owner. He said REALLY? FOR THAT THING? I immediately realized he had no clue what that was but didn't wana back out.

It is B&K EX-442 Sonata dual channel amp. That's all I know, has no information, no manual, not even a power cord. I don't even know if it works, but looks in great shape, despite a couple of scratches on the edge of the front plate. Been looking for a good dual channel amp for a while and took a risk on this guy.




I have a few questions now, because this is my first amp. Can I use regular RCA cables to connect my Marantz outs to this? I don't have anything else and I want to try it.

Also, Can I use the power cord from my computer? Looks the same. This amp says 900W consumption on the label though. Not sure my PC cord is up to that.

And lastly, if it doesn't work, how much would the average repair run in Chicago? In worst case I am out a hundred bucks.

zane77

You can use regular RCA's, but some name brand cables may sound better, and your computer powercord will work although some people believe that better power cords improves sound just like better interconnecting cables.

ravaneli

Scratch that. Left channel does not work. The guy agreed that I return it (he's kind of a friend and inherited that amp with a bunch of other equipment when he bought the house) but I would like to fix it if it's cheap. The right channel sounds great and the amp seems in great shape

Can anyone recommend me a Chicago amp repair service? Doesn't have to be a reputable dealer, anyone who can fix them is good for me. Also, what would that run?

falconcry72

Cool amp!:biggrin: Looks like it was made from '85 - '94, it's rated at 200 WPC @ 8ohms, 350 WPC @ 4ohms, it's a dual mono design, and it retailed for 1100 bucks.

I would definitely try to get it fixed. It may just need a fuse or some soldering; it's worth taking a look anyway. Open it up and see if you can see any obvious problems in the path of the channel that doesn't work.

Kex

Here is the same model for sale right here some time ago:

http://www.polkaudio.com/forums/showthread.php?85237-B-amp-K-EX442-Sonata-amp

It sold within 24 hours!

This link should bring up the specifications (along with other vintage gear from from B&K):

http://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=8&ved=0CIcBEBYwBw&url=http%3A%2F%2Fwww.bkcomp.com%2Ffileadmin%2Fcontent%2Fbk_support%2FFAQ%2FPrevious%2520Amp%2520Specs.pdf&ei=1iqcT9HsJ5PoiAKine2YAQ&usg=AFQjCNGdGo60G0BET76bhbYbGfXuy17SKw

• 200W x 2 @ 8Ω
• 350W x 2 @ 4Ω
• Production from 1990-1993

ravaneli wrote: »

... Can anyone recommend me a Chicago amp repair service? Doesn't have to be a reputable dealer ...

That's funny! Like asking "Do you know a car mechanic? Doesn't matter if he's any good!", but I think I know what you mean!

Good luck with the project.

ravaneli

the other channels sounds amazing. i will definitely try to fix it. Actually if someone can reservice it to replace caps or whatever.. i would invest in that too.

falconcry72

ravaneli wrote: »

...if someone can reservice it to replace caps or whatever.. i would invest in that too.

Good call. Congrats on the snag, and good luck on the fix!:biggrin:

transmaster

Wow what a steal even with a bad channel. I found another one of these amp's for sale else where and they want $500 dollars for it

Monster Jam

Keep it for the money you paid ($100). Its a no brainer. My local electronics shop would fix it for between $50-$100. Killer deal.

ravaneli

can anyone recommend a good repair shop around chicago?

OK here is what I did, and you let me know if I f#kked it up myself. When I first powered it there was no easy way to test it without rewiring the way speakers were connected. But I had a pioneer elite subwoofer that I am trying to sell (auto) lying right there. So I got a 'brilliant' idea - use the amp to power the subwoofer and use the subwoofer for home theater instead of selling it!

So I connect the sub preout from the Marantz to the BK amp, and use only one of the channels to the subwoofer. However I forgot that the sub is 2 Ohm Anyway, I played some music and the sub had something like pulse, i could feel it with my finger, but didn't really make any noise.. So I disconnect everything and tried it with speakers the right way. But now the channel that I had used to power the sub was not working. Did I f3kk it up myself?? All the fuses look good, and I didn't really go more than mid volume.. not even that. However there is no more even 'pulse' coming up from that channel.. not even when you touch the woofer of a speaker, and there was definitely a pulse before..

Geoff4rfc

Congrats on your amp deal. Isn't your sub a powered sub? It would have it's own amp. The sub preout from your receiver is designed for your sub and not an amp.

The amp is designed to be connected with to your receivers speaker preouts, providing your speakers don't already have amps.

ravaneli

The pioneer that I used for the test was passive, from my car.., that's why it was 2 ohm.

Come on Chicagoans... where do u fix your amps?

transmaster

I don't know about this outfit maybe somebody does but they do look like a place to take you amp to in Chicago

http://www.soundsclassic.com/

ravaneli

hmm, not that close, but I will give them a call to check them out. Thanks!

newrival

Hey, take it to deltronics. It's in downers grove, i believe. Not terribly far from you. Just down 355 and it's right off the toll way.

I've got an amp there right now, and they've done a few pieces for me at a fair price.

ravaneli

Found a russian fellow who inspected it for free and said it will cost me 80 to fix it and another 70 if I want to replace a few caps and resistors. This thing is 25 years old.. I think I am gona go for both. Cant wait to test it.

ravaneli

Picked it up today. Rewired my A7 once again and did two hours of listening to the same old songs I use for testing. It was 2.0 using my Marantz SR5006 for receiver and HTPC was hooked to the Marantz with HDMI.

As much as I would like to praise my new purchase, I was left rather underwhelmed. It sounded super clear. I have a huge living room with those high ceilings and during the piano intro into some songs the fidelity was incredible. Like a piano in my room! Those A7s play the piano really good! Here is the thing - my Marantz already played the same songs super clean! I could not find any audible difference in audio quality! Not even in loudness! It was NOT louder than my Marantz, although outweighing it by some 15 pounds and if you compare the amp sections only probably more than twice the weight of the Marantz amp. Nonetheless I did not notice some extra power. Bass was just as powerful to me as well. Perhaps slightly better separation of the drum beats, but I am really not sure. Even if there is difference it is too close for me to call. I don't know if my Marantz is too good, or the B&K is just from another day.
But let me leave on a positive note. I did not intend to listen to music for two hours. I just practiced my BH loop and let it play in the background very loud (-6db). Eventually i was breathless and drowning in sweat and discontinued my BH improvement and went to check the amp. It was barely even warm. Room temperature on the entire case! My Marantz however, even though used only for processing, was almost concerningly hot. Actually I have been concerning about that for a while, perhaps someone can tip me on what I could be doing wrong.

But here is the kicker: I have never before done two hours of listening to the A7s straight! They are fatiguing speakers. They were fatiguing with my Pio 521, Pio 1021, and Marantz 5006. But I did not experience fatigue this time, with the exact same (no EQ of any kind) settings. I did not find the A7s warmer sounding while listening, but they must be. The A7s are great for HT, but after even 30 mins of music I usally want to submerge my head on a bucket of cold water. I am pretty sure in the result but don't understand why I couldn't detect the warmness when I was trying. Oh well..

F1nut

Kinda boring here tonight, decided to read thru this one. For starters, you just got it back from the shop with new caps. They need to burn in. You are using an AVR as a pre amp for 2 channel music, never gonna get what that amp or any amp is capable of that way. Anyway, leave the amp in your rig for say at least two weeks (caps should be cooked by then) and then take it out. See if you don't hear the difference.

Drenis

ravaneli wrote: »

My Marantz however, even though used only for processing, was almost concerningly hot. Actually I have been concerning about that for a while, perhaps someone can tip me on what I could be doing wrong.

While using it as a pre-amp, did you remember to turn off the internal amplifiers? This is sometimes referred to as "Speaker A/B, etc...". My Elite AVR is room temp warm when it was used as a processor and internal amps turned off. On, and it's a whole different story.

ravaneli

I don't even know what you are referring to. I went through the Marantz menu and I don't see how I can turn the amp section off. I would expect it to be off if I don't use it anyway..

ravaneli

last night I did another stupid thing in a whim. I bought this just to check it out: Behringer EP4000 Europower Power Amplifier

http://www.parts-express.com/pe/showdetl.cfm?Partnumber=248-748#Reviews

As God is my witness, I have no need for this thing, but I was reading all night and all this power seems so cheap, I just wanted to check it out myself. Curiosity killed the cat. I want to try it driving the A7s and compare with the B&K. Also, I will rewire my car subwoofers to 8 ohm (they are dual 4ohm voice coil) and will see if it can drive two subwoofers for home theater. I will play with it for a month and will dump it here in the For Sale, hopefully for not too big of a loss If you are going to be interested please note, or pm me now.