Those are dynamic rms voltages based on music content. The subs are Rythm 2's with the coils in parallel so 4 ohms nominal. Room I estimate at 25 wide by 15 deep by open ended height (not a closed off room exits to kitchen and stairway). Mains are TLAH (bfm) with 6 midrange and 9 tweeters each wired series parallel to I think 6 ohms.
Subs have 1 channel of a DCI 4x1250N to themself so roughly 70V into 4 ohms.
Problem is those test tones are out of the bandpass of my subs, I would need a 50 Hz tone to reasonably judge level.
I like to measure pink thru the sub, by just letting it run thru x-over and sub high-pass as if it were music.
It's considerably more steady than music, but still bounces around some, so averaging is needed....(along with averaging of SPL for same time period if determining sensitivity or compression, etc.)
IMHO, all sub sensitivity specs should be determined like this, band-passed pink for intended use....Only caveat is that a true RMS meter with averaging is needed....
i'm a bit late, but for going really loud to my standards i need about 3.8v on my +/-90dB/2.83v (measured) speakers, most of the time it's a lot lower. The room is 4x6.5x2.3 meters. It may be the case that i have very sensitive ears and that i don't like it too loud but i do like deep bass.
I did own a 100dB/2.83v speakerset for a while (old classic) that had enough with 2.83v in my living room. I paired it with an low wattage tube amp i had also at that time (both are sold for way more than i payed for it, that was the purpose when buying them) and i kept it mostly at -12dBVU on the preamp (as there was no volume pot on the amp) and that was more than loud enough...
I did own a 100dB/2.83v speakerset for a while (old classic) that had enough with 2.83v in my living room. I paired it with an low wattage tube amp i had also at that time (both are sold for way more than i payed for it, that was the purpose when buying them) and i kept it mostly at -12dBVU on the preamp (as there was no volume pot on the amp) and that was more than loud enough...
Yes, and I admit to be rather surprised by that. Perhaps given average room sizes and speaker efficiencies, we just don't need all that much voltage out of our amps.
I own several old console stereos from the 1960s. All 100% solid state and all limited to about 16V RMS max. Meaning they should give about 5 volts output on my test signal at max clean volume. None of them need to be pushed that far to fill the living room, and even the whole house, with music.
I own several old console stereos from the 1960s. All 100% solid state and all limited to about 16V RMS max. Meaning they should give about 5 volts output on my test signal at max clean volume. None of them need to be pushed that far to fill the living room, and even the whole house, with music.
We tended to use much more efficient drivers back then.
I had some "modern" Richard Allan Pavanne bought in 1971.
I replaced them with Tannoy Berkley which are reputed to be very efficient.
But the Pavanne played noticeably louder at the same vol pot settings, even though both were 8ohms speakers with crossovers.
Later I managed to get a hold of T/S data for both to discover that the Richard Allan drivers were 2db to 4dB more sensitive than the Tannoy 385HPD.
Our speakers have become less efficient as the manufacturers chased extended LF bandwidth in exchange for efficiency.
Amp power was becoming cheap and the speakers were using that. Small boxes, low sensitivity drivers and bandwidth that at least matched the big boxes and big drivers of old.
But what I find really surprising with the poll is that so many, >38% of pollsters, need amplifiers with less than 4W. How efficient are their speakers?
I had some "modern" Richard Allan Pavanne bought in 1971.
I replaced them with Tannoy Berkley which are reputed to be very efficient.
But the Pavanne played noticeably louder at the same vol pot settings, even though both were 8ohms speakers with crossovers.
Later I managed to get a hold of T/S data for both to discover that the Richard Allan drivers were 2db to 4dB more sensitive than the Tannoy 385HPD.
Our speakers have become less efficient as the manufacturers chased extended LF bandwidth in exchange for efficiency.
Amp power was becoming cheap and the speakers were using that. Small boxes, low sensitivity drivers and bandwidth that at least matched the big boxes and big drivers of old.
But what I find really surprising with the poll is that so many, >38% of pollsters, need amplifiers with less than 4W. How efficient are their speakers?
I find that average levels are indeed less than maximum line level, i.e. max line level into the power amp is ~1Vac and the average output to the speaker is slightly less than 1Vac. That is for quiet music/audio. For me normal listening tends to show 500mVac to 2Vac as average and loud music can show averages upto around 5Vac (I watched Mike Oldfield, the tubular bells story last night. I turned it up about 5dB for that. Great to hear him playing alongside the reproduction from the "ORIGINAL TAPES").
But transients require more than 3times that for highly compressed/limited music and many sources can require upto 30times the average level to give a signal range that allows for all music types.
Maybe those 38% only listen to very compressed digital music as well as sitting close to very efficient speakers.
But transients require more than 3times that for highly compressed/limited music and many sources can require upto 30times the average level to give a signal range that allows for all music types.
Maybe those 38% only listen to very compressed digital music as well as sitting close to very efficient speakers.
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30 times the average level for peaks means 30dB. That's a lot. I've rarely seen recordings with that sort of dynamic range. Good dynamic classical might be in the 22-24dB below peak range, good rock and jazz sits around -18dbFS average. Many CDs are now mastered at -15dBFS
If the 38% who got 2V or less on my test tones were listening to a typical CD mastered at -18dB then their average voltage would be about 1V. That would put peaks at 8V. Not really hard for most amps. But it would be difficult to say what the SPL is at the listening position, not knowing the speakers, rooms, listening distance, etc.
If the 38% who got 2V or less on my test tones were listening to a typical CD mastered at -18dB then their average voltage would be about 1V. That would put peaks at 8V. Not really hard for most amps. But it would be difficult to say what the SPL is at the listening position, not knowing the speakers, rooms, listening distance, etc.
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One of the things I note is how power rail voltage drives expectations of high-powered amps and vice versa of course. But this doesn't have to be the case. My latest project uses minimum +/-50V rails and I'll never drive an inefficient speaker at a party with this amp. So the heatsink size, power transformer VA rating and rail fuses etc. are not set up to deliver high power that the rail voltage suggests. However, I like to have the extra voltage because it benefits the operating points of various devices in the amplifier and pushes the likelihood of clipping way outside my normal range of listening. Sure, this amp can provide way more than 8V at the output, but it wasn't designed for doing that - if you get my point.
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I don't put much thought into gain usually, just expect that the gain should be sufficient for giving me a good amount of sensitivity or 'feel' on the volume control - meaning I don't want to be at ear bleeding loud within 1/8th of a turn, neither do I want it to need 4/5th of a turn to hit normal listening levels. In practice my SS amps are usually operating between 22dB and 35dB gain.
How did I miss this thread for so long? Anyway, just saw it a couple of days ago and yesterday measured 0.77Vrms at first, then "ah heck, the people downstairs can take it for a few seconds!" and bumped it up to a whopping 1.2V.
One thing though is the impedance, I'd forgot that the drivers are 16Ω and who knows what the total impedance of the system avec xo is. I'll measure it.
Thanks Monsieur P
One thing though is the impedance, I'd forgot that the drivers are 16Ω and who knows what the total impedance of the system avec xo is. I'll measure it.
Thanks Monsieur P