I measured Carver Sunfire sub about 20 years ago for a hifi-magazine and it is a "wicked" thing! You can blow the fuse with it if you are not careful, because the amp is so powerful. It is a crazy audio product, but I do admire the ambition to force 20 Hz out of the smallest cabinet possible with raw power...
I think he paid about €700 for it from someone going out of business who needed a quick sale. So it was very cheap (relatively), especially considering it hadn’t been used much and was in excellent condition.
Yep, he hadn’t considered how much more power a sub would need, just that 250w sounded like it should be enough.
This is something I don't want to argue because that is indeed correct. If both the frequency response and THD measurement was coming from the same room and position, my assumptions and numbers are entirely off. However, the wording of the previous posts makes me think there are two different measurements being jumbled together. It looks like the 10% distortion comes from the manufacturer while the frequency response is the actual in-room measurement. I tried to explain why these two can't be really be put together the way you describe it. I think that would be an overly optimistic best case scenario approximation.
700 euros is indeed very cheap for this sub. It is around 3000 euros new and typically Genelec speakers retain about 80 % of their value on second hand markets, so anything below 2000 euros for this model is a steal.
Apparently not. Makes one think if the theatrical specs are too demanding? How loud do you have to go?
Oh, okay. I wasn't reading the discussion enough to know what is going on. If different measurement are jumbled wildly together, the whole thing is a mess I don't want to be part of...
Oh damn! Not -40 dB but 40 dB. I don't know why I have the negative sign there! Thanks for pointing this typo out for me! I'll fix it.
I’ve seen them go (second hand) for around €1,200 but more commonly about €1,500 or so. €700 was a great deal, or would have been if it was the right tool for the job!
85dB = -20dBFS, sub is +10dB in-band gain though. Sounds like a lot of SPL but it’s soon eaten up by big on-screen explosions with a lot of content down at 30-60Hz.
Oh, okay. Still, 700 euros is quite cheap for it.
According to this spec the sub needs to do 115 dB (85+20+10 dB), right? Genelec 7070A can just barely make that much sound on short term explosions measured at 1 m I think, but measured further than that there are clearly problems as has been established... ...anyway do we need to go over 100 dB? Would it be a loss if movies had explosions peaking at 100 dB? for my ears 90 dB starts to be a lot but then again I have aspergers and increased sensory sentivity.
Not quite, it’s in-band gain. You need to use a band-limited test signal. Using a broadband signal it would work out somewhere around 112dB. Also, in a small room you would typically calibrate to 79-82dB rather than the 85dB (= -20dBFS).
Not for music but for some sound effects we do. Don’t forget that at 30Hz, 60dBSPL is barely audible and we want to move enough air so there’s actually a physical sensation in the case of explosions for example.
Seems like a lot of blockbuster action/sci-fi movies do. And they have more LFE with setting the rumbles in jet engines/crashes. I've also noticed overall levels can be different on UHD disc vs streaming (IE I'll adjust my receiver's subwoofer level adjustment on my phone when I'm watching an action movie on UHD or streaming). With streaming, I might have to raise the volume 5dB for Atmos over DD+ streaming and independently raise subwoofer level. Then on some UHD discs, I might have to go well below -5dB on its TrueHD/Atmos track from the previous streaming (and might also start lowering subwoofer level more when there is an explosion).
one of the reasons could be lossy vs lossless, i noticed that stuff under 20-40hz is actually quieter (and less "clean") on lossy formats
It’s definitely sound level of the audio track and not format. For example Star Wars TrueHD Atmos is close in volume to it on Disney+. I do have to raise levels for it. If I put on Top Gun Maverick after that, then I found it was a little louder than other UHD movies and have to go further than -5dB
It’s not just explosions, it might be thunderstorms, vehicle crashes, rumbles or whatever, depending on what effect the director wants. And of course, theatrical sound systems are not designed/calibrated to be suitable for only the movies you watch but for all films.
Here is where things start to get complicated, for a number of reasons. Each of the main (front) speakers in a theatrical system will already have one or two subwoofers built into them. Then there will typically be at least two banks of subs, one bank doing bass management duties for all the surround/diffuser speakers (which normally don’t go lower than ~55Hz) and another one or two banks dedicated to reproducing only the LFE channel. Consumer 5.1 (or greater) systems are quite different, the main speakers don’t have subs and the surrounds are also LF limited, so the subwoofer has to do double duty, reproducing both the LFE channel and doing bass management duties. Playing back an actual theatrical mix on a home system would result in the sub spending a fair amount of time in an overload condition. Despite what the advertising might state, consumers will very rarely ever get the actual theatrical mix. Exceptions could be low budget films, that don’t have the money to create multiple mixes but typically these would be relatively simple dramas that don’t use high LFE levels anyway.
There’s no audible difference between lossy and lossless film formats even in the most sensitive hearing band, let alone the least sensitive band! Yet AGAIN, you’re just making up nonsense and “noticing” things that are not “noticeable” or aren’t even there to start with!
With my 7.1.4 home theater, I have observed quite a difference with normalization and mix of the LFE channel depending on mixes of that title (that a contracted company is doing for a streaming or disc home media delivery). I've noticed I might need to change volume levels more often with that system (which includes full sized tower mains, tonally matched center and surrounds that are relatively large cabinets) vs my soundbar in my bedroom (that includes a small subwoofer and two small surround speakers that try to reflect Dolby height and side). I think part of it, apart from me watching more streaming TV content, are that I don't have full sized speaker drivers being directly aimed at my listening position.
