Solid-State Power Amp Adventures

Discussion in 'Power Amps' started by Marvey, Jan 24, 2017.

  1. Kolohe

    Kolohe Acquaintance

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    Somebody already popped them both open, here.
     
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  2. Purastikku

    Purastikku Rando

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    Good to see Nuforce moving away from Class D, I had a brief stint with the STA-100 and while plenty powerful given its size, the overdone warmth and bloated bass did not win me over. Plus a constant background noise/ hiss, even without any input, loud enough to be noticed 2 meters away (with low-sensitivity speakers, 86dbm). It was apparently a widespread issue in Nuforce amps at the time, and a real shame given the size/ power/ price ratio was great.
     
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  3. yotacowboy

    yotacowboy Almost "Made"

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    From what I've gathered on the innernets, Nuforce did some restructuring/rebranding where the core of the company sold off the lower-end products and did a restart on the higher-end, branding-wise, rebranded as Nuforce Prime (NuPrime). the company that bought the rights to the lower end gear is Optoma, who does mostly projector/HT stuff. IOW, the STA200 amp seems to be a bit of an outlier.
     
    Last edited: Dec 1, 2017
  4. jowls

    jowls Something related to poop - Friend

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  5. Armaegis

    Armaegis Friend

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    It should be enough unless you're going for gorilla levels of slam.
     
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  6. Priidik

    Priidik Friend

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    F4 is unity voltage gain.
    Unless you go bridged, single F4 can take SE from ADI, that means from line out -->F4--> HE-6 will do 0.9 W of power. That's like barely over 100dB, with 0dBFS content.
    Some music is less loud.
    For loud listening this is not enough, anyways. One option is to use headphone outs, which are slightly more hot, but still on the edge of being a bit weak.
    Balanced would have roughly enough voltage, but that means 4x F4 monoblocks.
    When the ADI SE can drive these loud enough for you on its own, then it will do roughly the same with F4, only likely with more grace and grip.
    From specs ADI hp amp single ended only barely hits current limit before voltage limits for HE-6's 53 ohm load, so the claimed 1.5W power the HE-6 will get.
     
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  7. jowls

    jowls Something related to poop - Friend

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    Thanks to both. I guess it’s more an indulgent want than a need (audio jewellery, e-peen, whatever - it is a fairly unique opportunity as it is built by the man himself), but from the sound of things it may be largely redundant in my current setup :(
     
  8. Armaegis

    Armaegis Friend

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    You're on a specialized forum that caters to a niche within a niche with nutjobs hooking up thousand dollar bazoos to their noisemakers. You go spank that e-peen as much as you want :punk:
     
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  9. atomicbob

    atomicbob Friend

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    The ADI-2 Pro can be set for +19 dBu reference output. That is 6.91 Vrms at 0 dBFS for a sinusoid. HiFiMan is not clear about the HE-6 specification. They publish 83.5 dB; ... dB what, per volt, per mW, per ?? If we assume a common dB/mW then 0.95 W will produce 113.3 dB for 0.95W max. Assuming also a 10 dB peak to average ratio for the music, average listening levels would be around 103 dB. That is VERY LOUD. Personally I listen between 75 and 85 dB and would have no problem with the proposed setup. YMWV.
     
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  10. jowls

    jowls Something related to poop - Friend

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    Thanks. At this stage it would be driving PMx2. PM-2 is 102 dB in 1 mW.
     
  11. atomicbob

    atomicbob Friend

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    Well at 32 ohms and 102 dB/mW you can achieve 133 dB SPL at +19 dBu consuming 1.5W. With a 10 dB peak to average that implies listening at 123 dB with peaks to 133 dB SPL. Not how I wish to ruin my hearing but others may enjoy that sort of thing, for a short while.
     
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  12. Forza AudioWorks

    Forza AudioWorks MOT: Forza AudioWorks

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    For a very short while indeed.
     
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  13. Peter

    Peter Rando

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    I just measured the DC offset of my amp from Aliexpress. 1 channel is 0.5mV while the other is 1.3mV. Seems healthy ;)
     
  14. Neal

    Neal Almost "Made"

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    I grabbed one of these for $499 of amazon, figured I could return it if it sucked. Initial impressions - this thing is better than Vidar...
     
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  15. Forza AudioWorks

    Forza AudioWorks MOT: Forza AudioWorks

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    In what way?

    Shit, alright, you don't need to answer. If this product is at least similar to my JOB 225, then yes it's a beast. Damn, tempting to have it for $499. What. A. Deal.
     
    Last edited: Dec 7, 2017 at 4:20 AM
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  16. yotacowboy

    yotacowboy Almost "Made"

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    Have about 150-ish hours on mine so far. Won't give any more impressions seeing as how I'm waiting on Freya+Gumby to settle in, so there's too much going on in my system right now, BUT, just running Bimby to Magni2U to STA-200 kicked the crap out of my old Cayin integrated.
     
  17. Forza AudioWorks

    Forza AudioWorks MOT: Forza AudioWorks

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    One thing's certain. This is a marvelous deck no matter how you slice it. JOB 225 is a steal for $1699 and this is probably the same deck in fancier clothes for less than 25% of that.
     
  18. Neal

    Neal Almost "Made"

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    More detailed; more cohesive from top to bottom. It's a little on the dry side though. I only have a few hours on it however.
     
  19. Forza AudioWorks

    Forza AudioWorks MOT: Forza AudioWorks

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    Yeah, I know what it is now. Just bought one. Fun times ahead, I couldn't resist.
     
  20. Sylafari

    Sylafari Acquaintance

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    Started to look for a solid state speaker amp, it is insane to me how they are so expensive when compared to when I was shopping for headphone amplifiers (why is this?).

    Bought a STA 200 (coming tomorrow) and a Vidar, will return the one I prefer less.
     
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