Sunfire MK4 Subwoofer Repair

[@viciouspoodle5543]

Just an FYI for any of you that have a rattle or issue with the passive radiator: you ran replace the PR with an Earthquake Sound SLAPS M10 PR and improve the performance from stock. This is a drop in fit, no modifications needed. The SLAPS M12 will fit the 12 inch Sunfire with a very slight widening of the opening (bolt pattern is identical). I've posted vids of them both in action with these new PR's.

[@zarrdoss]

The caps Carver used were not that great and wear out. Good job fixing it. I just sent mine into Flannery's audio repair and he replaces all the caps with better ones and gives them a tune up, now it sounds fantastic!

[@hauhoang1637]

Thanks for sharing

[@craigc339]

Hi, thanks for the video. I was able to do the same to my Sunfire True Sub Signature which brought it back to life. Cheers.

[@peppino5413]

Recommend re-soldering solder joints before removing solder. This helps re-alloy 63/37 solder and adds flux which helps with the de-soldering process. Try heating one solder joint at a time and walking / rocking it off the board one side at a time until component is free to be removed then use dry fluxed solder wick to clean the PCB land holes with soldering iron. This will minimise PCB damage. Works well for me. Try using ESR checker to identify faulty capacitors.There is one good one ; MODEL MK5 made in Russia and powered by 2 x AA batteries.

[@miguelrueda4714]

So I need some help some one just gave me one of these speakers but I have no idea how to set it up can I please get some help on how to connect it

[@noahderrington5156]

I have a Sunfire HRS8 which suddenly started making a full volume buzz at 3am which didn’t make the wife or neighbours happy! 😬 I was thinking of re-capping it but haven’t done this before. I can’t see any obviously failed components but, it’s reassuring to know you fixed the problem by doing this. Where is good to order audio quality caps from?

[@robertrangelak]

Guys. I sent my amp to carver repair and still sounds like crap. Any recommendations on a repair place?

[@damson2809]

Is this sub a good deal at $175? How is compare to SVS

[@brewswillis9783]

I have an original True Subwoofer that intermittently pops and/or buzzes loudly (whether playing music or not) that I have visually inspected every single component under magnification and can see nothing amiss. Any ideas where to focus on or narrow down the search? Thanks!

[@hauhoang1637]

I would first inspect all the solder joints, specially under the heavy components hanging sideway. Vibration might have loosened those joints over the years. If they all look OK, perhaps the output power transistors should be inspected/replaced.

[@brewswillis9783]

@@hauhoang1637 Thanks for the suggestions!

[@mathiasleturcq8485]

Did you find a solution for the buzzes ? My Sunfire mk2 buzzes after several hours of operation with or without sound sources.

[@jacksimpsoncl]

Excellent video, my subwoofer decreases its power, it stops sounding after a few hours but it stays on, I checked cables and cleaned, but I can't find the fault, there are some capacitors that have silicone between them but they seem well connected but I don't know if that It's normal, do you know what fault it could have? Thanks a lot

[@hauhoang1637]

That's interesting. I have seen car amplifiers with a "throttle back" feature which reduces the output power when the amp gets too hot so it doesn't go into thermal shutdown. If that's not an intended feature in your subwoofer, I don't know what anomaly would cause the same effect.

[@hongseng-o4e]

amplifier watt ?

[@keng3545]

Hi I have just replaced all output transistors and caps , there are 2 jumpers which are resistors JP1and JP2 are blown and cant see what they were , Can you help ?

[@hauhoang1637]

Pause the video at 2:44 and you see two resistors with a black band - which to me look like O-ohm 1/4 watt leaded resistors.

[@tommybimmer73]

www.resistor.tw/spec-en-zo.htm

[@robertfalleur]

Great job dining and fixing the issue. Did you replace anything more than the two caps?

[@hauhoang1637]

Nope. Those are the only two components I replaced. Thanks for the comment.

[@rv112xy]

That worked for me on the MK II too, thank you! Is your's still fixed?

[@hauhoang1637]

That's great. Yup, mine still works. Don't expect those caps to go bad for the next few years.

[@rv112xy]

@@hauhoang1637 I'm in contact with a technican of Sunfire. He said that the MKII and MKIV subwoofers have cheap caps and will fail after 15 years. He recommend the original True Subwoofer because that one was handcrafted with US caps and not chinese ones. Did you replace all the other caps aswell?

[@hauhoang1637]

Thanks for the info. I haven't replaced any of the other caps. There are quite a few of them. The two I replaced sit next to the power transistors, run slightly hotter than the rest, and therefore should have relatively shorter life.

[@BiGJ30713]

Thanks very much for your illustrations. I just opened mine with the same capacitor bulging out. I intend on fixing it. Can you please show me how you hook this sunfire sub to your system. Am using Sunfire True Subwoofer Signature with Yamaha DSP-A1 Natural Sound AV Amplifier. With Two Klipsch Forte Floor Standing Speakers. Thanks. John.

[@BiGJ30713]

Also there are two inline 7.5 amp 250 volt fuse inside these. One should replace them too. Mine is blown too.

[@aggressors1821]

i have 2 sunfire subbs but both of them needs new "volym/level" thingi , some one know where to get this ? great video ,i have alredy replaced most of the big caps

[@hauhoang1637]

I had no issue with the volume control potentiometer and therefore didn't look it up. It's not a component that gets used often so I doubt it would go bad. To ensure that it's securely grounded, you may want to remove the plastic cap, clean and retighten the nut and washer that hold the potentiometer in place. If that doesn't do the job, spray contact cleaner down the shaft of the potentiometer while rotating it back and forth a few times to remove oxidation or contamination buildup between the wiper and the resistive element.

[@aggressors1821]

@@hauhoang1637 thanks

[@stuartwalsh8891]

I had issues with my Volume and cleaned it with DeoxIT spray. Works perfect now

[@chenglo8999]

Would Mk2 have similar setup? Ill open mine soon to chk. Just curious

[@hauhoang1637]

The output stage usually doesn't change much. Dan Dunham's MK2 video at 3:15 shows a similar components and placement.

[@chenglo8999]

@@hauhoang1637 pulled all the same caps out. They all look normal though but shall see if it fixes my issue. Im also replacing the big black ones.

[@djsteinotc]

Just bought one for $50 with the same problem. I will try this fix. Thanks for the video.

[@marshkid1]

How did it go?

[@freedi74]

Well done and you were lucky ... I have mk II and it's great. I also have three damaged Sunfire amplifiers: 2xarchitectural and one EQ Signature. I will resuscitate them :)

[@hauhoang1637]

Thanks. I had the 5ch Cinema Grand for about 10 years. It worked great except for the flaky auto-on detection.

[@Laissez_Faire]

Next time change all six caps. The two you changed and the four right in front of it

[@MyIronman8]

Lucky you good find you have