Powering Floor Standing Speakers - Amp/Receiver Questions especially Fosi

TheRealCher on 23/04/2025 - 09:15

Hi everyone
Main question - is it possible/worth it to power klipsch floor-standing speakers with a fosi, instead of a Yamaha or something similar?

My Harman Kardon BDS 280 won't switch on - I'm going to take it down to a hifi repair shop and see what can be done. It's only 4 years old but the technology inside is ten. I love it dearly.

In the meantime I have a set of Klipsch KD 52f floor-standing speakers with 8 ohms impedance that I'd like to set up for music. I want to run into it a cd player and a record player that already has a phone preamp.

I've been seeing talk of people running setups with fosi amps - BT20A, for example. If that's possible, I imagine I'd have to send the record player and the cd through a line in switch before it gets to the Fosi.

Is anyone using these amps (sub 300) to power their own set ups with floor standing?

Alternatively, should I just go with a respectable name brand entry level receiver like a Yamaha or Pioneer for around 5-6 hundred.

I want to go new - having disabilities makes checking out second hand stuff difficult. The only other option is flying blind and buying off cash converters website something old school reliable for around 150 until I can get the BDS checked out and fixed. Or bikies.

Thanks for any suggestions you can give. Apologies if I haven't given enough information as my knowledge is limited - please ask nicely and I'll do my best :)

Electrical & Electronics Amplifier AV Receiver Speakers

Comments

  • Protractor on 23/04/2025 - 10:04
    +1

    If it's any sort of reputable hi-fi repair business, chances are your sick unit can be repaired successfully. Unless for some reason, you and or lightning fried it. Most good high end audio amp circuits have internal layers of protection ,beginning with a very low amp fuse (or a few).
    I'd be waiting for a diagnosis.

    For your plan B ,It may even be quicker to contact Fosi direct, describing what you want to do, with what you have and they 'may' have some tips or suggestions to make it happen successfully.

    • TheRealCher on 23/04/2025 - 10:53

      Great - thank you for the tips re plan a and b. From what someone wrote below, b may need to be an option given the speakers.

  • rumblytangara on 23/04/2025 - 10:14
    +3

    Fosi- look for a model that will do 200W per channel at 8 Ohms as per the speaker specs and you should be fine (though the Harmon is only rated for 130W)

    Old school audiophile amps will be Class A or Class A/B which involve big chunky transformers and heat sinks, hence the size. Class D amps like the Fosi (and load of other brands) are much smaller and lighter, but can put out just as much power.

    (Personally, I would rate a cheap and cheerful Fosi to be about the same level as a Harmon Kadon DVD player/amp anyway)

    • TheRealCher on 23/04/2025 - 10:52

      Thanks for clearing up how much power I need (I get confused between wattage and ohms and whether it's overall or per channel). What you're saying, if I'm right, is that the Harmon would underpower the speakers - which makes me suspect it could damage the speakers as well?

      • rumblytangara on 23/04/2025 - 10:59
        +1

        which makes me suspect it could damage the speakers as well?

        Well, if you're not turning the volume way up it should be fine. Guessing you've been running this gear for years without a problem.

        • Protractor on 23/04/2025 - 11:03
          +1

          +1

        • TheRealCher on 23/04/2025 - 11:38

          I'd been using it with these: https://www.hifispecs.com/jbl-arena-180/
          And a powered sub woofer. Definitely not running it with the volume way up because of auditory sensitivities. I'm now running those speakers through an ONKYO TX-SR393 5.2 and it seems good. Maximum volume I go up to is 60.
          The Harmon just didn't turn on. Thought it might be batteries in the remote but no luck.

  • stickingly on 23/04/2025 - 10:38
    +3

    People pretty much give away quality old stereo amplifiers on facebook marketplace (I got the Cambridge Audio and Denon amplifiers that I use off hard rubbish). If you find one close by, could you offer someone an extra $20 to deliver it for you if you can't pick up (I have done this for people before)?

    • TheRealCher on 23/04/2025 - 10:48

      Definite possibility. I'd have to join the evil empire again but welcome to the machine lol. Is 2nd hand amplification worth it - for instance, I know with speakers, it is, but how would amps go?

  • Atomik17 on 23/04/2025 - 12:15

    Get a wiim amp pro

    • TheRealCher on 23/04/2025 - 12:30

      i have looked at it - my concern is that it wouldn't be powerful enough for those speakers

    • rumblytangara on 23/04/2025 - 14:20

      60W per channel on speakers that are specified for 200W? Not ideal.

      • Mechz on 23/04/2025 - 17:10

        60w per channel is plenty for the speakers. OP isn't running high volumes.

      • Atomik17 on 24/04/2025 - 07:47

        I have kef q350s and a wiim amp it runs it beyond listening comfort.

        • rumblytangara on 24/04/2025 - 10:14

          You're comparing single driver bookshelf speakers to triple driver floorstanders, not sure that's really a meaningful comparison for amp recommendations. Without a lot more detail, this is like talking about the great fuel efficiency of your diesel SUV when someone else is running the petrol model.

          • Mechz on 24/04/2025 - 12:12

            @rumblytangara: 200w is the max input. They really don't need anywhere near that to run perfectly acceptable volumes.

  • rumblytangara on 23/04/2025 - 15:57
    +1

    My Harman Kardon BDS 280 won't switch on

    10 year old amp… most likely problem is a blown capacitor. This could be an easy problem to identify and fix if you're handy with a soldering iron.

    Edit: Messing around in a power amp is potentiality electrically unsafe. You need to make sure you discharge the big capacitors safely before poking around the PCB. Would suggest reading up on this or avoiding it entirely if you don't know what you are doing.

    • TheRealCher on 23/04/2025 - 18:39

      Will avoid :) but this may be helpful when I take it in for repair

  • heysi on 23/04/2025 - 18:29
    +1

    Just got a Fosi Audio BT20A Pro today, it only has bluetooth and one line in so you would need a switch to use multiple inputs.

    The BT20A Pro is advertised as 300W but they include a table that shows max output at 259W @ 4 ohms and 129W @ 8 ohms with a 48V power supply. Most listings only include the 32V supply which works fine for my bookshelf speakers, testing it out via bluetooth I didn't take it past halfway and it was plenty loud.

    • TheRealCher on 23/04/2025 - 18:42

      Thanks… If I'm understanding correctly, that would be 65W per channel @ 8 ohms, using the larger power supply? (Volts, watts and ohms confuse a little)

      • heysi on 23/04/2025 - 19:18
        +1

        That's my understanding too, but for measured results check out this review and the test @ 8 ohms with both channels driven resulted in 100W max power with the 48V supply.

        If you're interested in power consumption, I just tested mine with a smart plug monitor and it only used a constant 3-4W, again testing via bluetooth and my 32V supply.

  • kevitkotw on 28/04/2025 - 23:38

    I've just been down the mother or all rabbit holes with it ending up with a set of Sonus Faber Lumina 5's. Still choosing an amp though.

    I'm loaning a NAD C399 currently, it sounds very nice and has oodles of power… the smaller ones would probably suit better to your speakers. Dirac is a software that comes with these and what it can do after you measure the sound response in your room is remarkable. The module is 'free' next month on a promotion.

    I don't know your budget, but a couple of suggestions.

    Marantz M1 - approx $1600.
    It's super interesting imo craps all over Wiim's offerings (more expenive though). I'd considered this while I look for a epic amp bargain.

    Rotel R-6000 - ~$3200 - this amp was retailed at over 6k, and is currently half price. Looking into it, it is better than the very highly regarded Rotel 1592mkii, and at half price it's cheaper. It's a tank and should last decades. I really want to trial it in my home as an alternative to the NAD

    Others worth looking at imo:

    Marantz Stereo 70s
    Audiolab 6000/7000
    Eversolo DMP-A6
    Cambridge EXA100

    I realise these are more expensive than the hundreds you were talking about. Regarding the Chifi (Fosi, Topping etc), I looked alot into them too, and after hearing the difference between the Marantz M1 and the more expensive ones, decided to go more expensive.

    The M1 was stunning for it's price and I'd say is leagues better than the cheaper Aliexpress/Amazon offerings, but the expensive speakers I bought did not sound as good. I do think it would be very very nice with your speakers.

    My list is mostly integrated amps, but I hope there's something useful there. If I was looking for a power amp and thinking about 2nd hand, I dont think you could go wrong with NAD. They have a very consistent sound over their range, and are extremely reliable.

    Good luck with your search!

    • TheRealCher on 29/04/2025 - 05:40

      really helpful - thank you. I think at the moment, saving up may be the thing. I'll put the receiver in for repair and if it can, great. If not, fine. The chifi seems good for smaller set ups, but while I'm still studying and on a very low income, I just don't have thousands to put down. I'll see what's in the 2nd hand market around town…
      I guess I'm surprised at how expensive the entry point is here for an amp that will be reasonable. It's at least 1k.

      • rumblytangara on 29/04/2025 - 10:05
        +1

        Ignore the above advice. It's frankly terrible and audiophile snobby but weirdly in the wrong direction.

        Rotel R-6000 - ~$3200 - this amp was retailed at over 6k, and is currently half price. Looking into it, it is better than the very highly regarded Rotel 1592mkii, and at half price it's cheaper. It's a tank and should last decades. I really want to trial it in my home as an alternative to the NAD

        He is recommending a 3-6K amp for a pair of budget floor standing speakers. The speakers are closer to 1K in Oz. If you seriously get into audio, you will probably move along from the speakers anyway. In the US, these speakers and the entire KD line are sold exclusively at <drumroll> Walmart

        What you hear is Speakers >> Amp > DAC. This is how you prioritise the spend.

        I guess I'm surprised at how expensive the entry point is here for an amp that will be reasonable. It's at least 1k.

        Don't go out and spend 1K on an amp. Stick to what literally anyone else has said in this thread- the recommendations are not only because everyone is cheap, but because they know you are not sitting at home with a 10K speaker setup in an acoustically treated room, and are scaling recommendations accordingly. Nobody is going to suggest Nelson Pass monoblocks here- get the existing gear fixed, or go cheap and cheerful Chinese Class D new, or get an old Class AB amp secondhand.

        If you like the speakers, more power to you. But don't be mislead into thinking that a much more expensive amp will make them three times (or whatever) better. The advice was like telling someone to put 98 petrol in a Camry- a great car that gets zero benefit from more expensive petrol.

        • kevitkotw on 29/04/2025 - 17:01

          Let me clarify. I was not for a second suggesting buying new (unless maybe a speaker upgrade was a desire in the future). If buying 2nd hand was an option, suggestions regarding a history of "built like tanks" is how I'd go about the used market.

          I was sharing the results of my online research, and I started by saying what speakers I was looking to pair an amp with ($5-6k). I'm a fan of buy once, buy right in my old age. I got the lightly used ex demo Lumina V speakers for <$3 fwiw.

          This journey of mine started with the chifi brands. I am ALWAYS looking for bang for buck and those brands seemed to have it. I was very keen to find one that was a diamond in the rough so-to speak. Honestly I wasn't even looking at the $3k for speakers price range but I fell in love with the sound. Before them, I have been listening to Edifier R3000PRO for years and I love their value. The R3000Mkii is $750 currently and I think they'd be hard to beat in that price bracket considering they're powered.

          I listened to a couple of the Chifi brands on my speakers and they were not up to the task. The more expensive ones I mentioned seemed like diamonds in the rough, That Rotel is definitely over-specced, but would also be endgame (for me at least).

          The general advice given is to spend roughly the same on speakers as the amp. I tried to beat the system and go cheaper, but I fell short of feeling satisfied. If I'm becoming an audiophile snob, that is by accident. Having my own health issues that have kept me largely couch bound for over 4 years may have had something to do with it…

          Anyway, @TheRealCher, sorry if I came across as suggesting the exact ones I've been looking at were the answer to your situation. It wasn't my intent. I was hoping it would lead you to a 2nd hand reliable brand (Rotel/NAD). For me, music is something that can bring emotion when I'm feeling trapped in the house, so I've blown my initial budget considerably. There will be many many many hours enjoying them, so I'm ok with it. I hope whatever you end up with brings you joy.

          • rumblytangara on 29/04/2025 - 21:00

            @kevitkotw: Fair enough. Just keep in mind what the OP is starting with.

            The general advice given is to spend roughly the same on speakers as the amp.

            This probably works once you reach a… certain level of speaker. Before hitting that threshold, source and amps are really not going to scale. And USD$250 Walmart speakers using budget aluminium drivers are imo not reaching that threshold.

            Personally, I believe that the the way to go for good but inexpensive sound is to build your own speakers- prototype cabinet sizing, take your own measurements and figure out room treatments (this last point unfortunately conflicts with family living). This also helps you sidestep a lot of the woowoo snakeoil BS that infests the audio word. But I would not suggest this approach to anyone unless they have a lot of time and an interest in technicalities.

            • TheRealCher on 30/04/2025 - 04:45

              @rumblytangara: I really value everyone's input here - I know there's lot of viewpoints and I'm just trying to begin and work out what will be best for me.
              Ten years ago I had a soundbar for my tv and an all in one for my cds. Over the last few years, I've been with my JBL's and my Harmon with a sub woofer and it's done a great job, with my xbox and blu ray added.
              Now I've got separate parts - cd player, record player - but as a renter I'll never have the space or the money to afford big things, let alone have them at a volume they deserve. I have lots of headphones to enjoy that kind of feel but I'm wanting a space around me where I can just let the music breathe.
              I'm autistic and ADHD, so music brings me a lot of pleasure but also calm, but it's also really confusing when everyone is coming at things from different perspectives. It's hard for me to explain in words the concept that I have, and I thought posting here might bring some clarity…
              I don't have a thousand to spend - it's more in the 500-600. I know that's low but that's where I'm at.
              I'm going to see if the HK can be fixed. I hesitate at chifi because I can't find anything that suggests someone is using it regularly to take in the things I want and power out through the speakers I have for this new set up (the Klipsch).

              For the price, I can see myself getting the basic model yamaha, pioneer, or HK, or possibly the Wiim Vibelink. If I can find something in my area second hand, great, but regional QLD is… well, we'll see.

              Maybe in 5 years I'll have money for more… or I'll need to get rid of all of it so I can live in a small house. But it would be nice to have something that lasts that long, or that can be repaired easily, so I can enjoy my music. That's what I really want :-)

              • rumblytangara on 30/04/2025 - 10:03

                @TheRealCher: Yeah, sorry for slamming your gear. I was just amazed that someone was trying to tell you to look at 3K amps for your speakers.

                I have a couple of friends running Fosi amps quite happily but I have no idea if they'll match with the speakers you have. If I was going to do a new speaker build with lower power requirements, Fosi or SMSL is exactly where I would start (in part so I could compare them with my existing amp to try to hear any differences).

                SMSL is what I set up for my nephew who is into composition, but they're driving small bookshelf speakers for a bedroom.

                • TheRealCher on 30/04/2025 - 10:40

                  @rumblytangara: It's ok…people are trying to be encouraging :) the input confusing but I know people are going, we want you to have the best sounds possible. Unfortunately situation and budgylimit that 😂
                  the speakers were half price last year, they had a good name, and they were affordable. They're a step up, but I know they're not even mid fi.
                  My other JBL set up is great - I just don't have the space where is for my turntable and I want a place in my home that's not in front of the television.

                  So we'll see :) I've learnt here that there are more steps to go 😂 that there is always someone who knows something and when you've got something in between (like floor standing) it complicates things. The journey continues!

                  The Fosi amps seem also good when used as pairs - that might be an option but my head can't process how the set up would deal with channels that way.

                  • rumblytangara on 30/04/2025 - 10:45
                    +1

                    @TheRealCher:

                    The Fosi amps seem also good when used as pairs - that might be an option but my head can't process how the set up would deal with channels that way.

                    That's called bi-amping. Short answer- don't bother wasting the time. Just get a single amp that has enough power and call it a day.

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