I am unclear on speaker sensitivity. My desire is to build a new set of speakers for my 6LU8 amp. My current speakers are rated at 89db, I presumethis is the 1w 1m spl.
Now here is my question. If a driver has a rated SPL of say 90db, that means that my speaker build with that driver will not have appreciably more spl that my current speakers regardless of the box I put it in?
Or, another way, if I want double the "loudness" of my current speakers, I think I need an additional 3db of sensitivity (?), and I need a driver rated at at least 92db spl?
Roger
Now here is my question. If a driver has a rated SPL of say 90db, that means that my speaker build with that driver will not have appreciably more spl that my current speakers regardless of the box I put it in?
Or, another way, if I want double the "loudness" of my current speakers, I think I need an additional 3db of sensitivity (?), and I need a driver rated at at least 92db spl?
Roger
Without changing the shape of the cabinet.....changing the port...or changing the crossover....etc; what you typed is generally correct.
Amplification is the obvious way to increase spl . A cost effective way (less than $100) to step up voltage into the amp/increase gain/loudness would be with a preamp.....and depending on your amplifier +/- a channel level converter (like the ArtClean Box Pro) The risk with adding anything into the chain is increased distortion and potential for introducing a ground loop.
Amplification is the obvious way to increase spl . A cost effective way (less than $100) to step up voltage into the amp/increase gain/loudness would be with a preamp.....and depending on your amplifier +/- a channel level converter (like the ArtClean Box Pro) The risk with adding anything into the chain is increased distortion and potential for introducing a ground loop.
Cptx, does that mean that changing the size port etc can increase sensitivity? I assume a non vented box would reduce sensitivity compared to free air rating?
Double the loudness needs 10dB more. Only 3dB more is "slightly" louder.
A port does not affect mid-band sensitivity.
^^^
Yes, a correctly sized/tuned port relative to an appropriately sized speaker cabinet would only have the potential to increase SPL in the lowest human hearing frequency range.
Yes, a correctly sized/tuned port relative to an appropriately sized speaker cabinet would only have the potential to increase SPL in the lowest human hearing frequency range.
That is usually the sensitivity for an infinite baffle (2pi half space).
For bass range this will be reduced by 0 to 6 dB, depending on the speaker placement.
0 dB for placement in or just in front of a wall.
- 6 dB for free space placement, without any room gain.
If you want free louder bass and better overall sound, recess the speakers into the wall, with their fronts flush with the wall surface.
No higher sensitivity, higher gain, or higher amplifier power is needed. Usually the tweeters should be at seated ear level.
I have done this for several clients and it has worked out well in all cases.
No higher sensitivity, higher gain, or higher amplifier power is needed. Usually the tweeters should be at seated ear level.
I have done this for several clients and it has worked out well in all cases.
When you say 'loudness', do you mean,
1. Maximum speaker output, or
2. Output per Watt?
1. Maximum speaker output, or
2. Output per Watt?
No.
Thanks. I though that the 3db down point was half as loud.
My desire is to try to build a speaker with more sensitivity than either of my current ones used with this amp. The 3-5 watts drives the speakers to a comfortable listening level, but I think I am losing some dynamics. Also, I have enjoyed speaker building in the past. I was thinking that a full range speaker might be the answer, until I saw that the drivers were mostly rated at nearly the same spl as my speaker's sensitivity of 89db.
I know I could build an enclosure to enhance the low frequencies, but many of the full range drivers have about 90db spl across the frequency range.
How would you suggest I find a proven design of driver(s)/enclosure that would have noticeably higher sensitivity than my current ones? Which by the way are a refurbed pair of Advent Graduates, and a pair of Polk Monitor 50s. The former bought to be driven with a Dynaco ST120 that has since gone by the wayside, the Polks are/were part of my HT system. I interchange the speakers sometimes, and have yet to decide which speaker I like better with the little amp. They certainly sound different. The Polks are more neutral, the Advents more forward midrange.
My desire is to try to build a speaker with more sensitivity than either of my current ones used with this amp. The 3-5 watts drives the speakers to a comfortable listening level, but I think I am losing some dynamics. Also, I have enjoyed speaker building in the past. I was thinking that a full range speaker might be the answer, until I saw that the drivers were mostly rated at nearly the same spl as my speaker's sensitivity of 89db.
I know I could build an enclosure to enhance the low frequencies, but many of the full range drivers have about 90db spl across the frequency range.
How would you suggest I find a proven design of driver(s)/enclosure that would have noticeably higher sensitivity than my current ones? Which by the way are a refurbed pair of Advent Graduates, and a pair of Polk Monitor 50s. The former bought to be driven with a Dynaco ST120 that has since gone by the wayside, the Polks are/were part of my HT system. I interchange the speakers sometimes, and have yet to decide which speaker I like better with the little amp. They certainly sound different. The Polks are more neutral, the Advents more forward midrange.
Good thread on Betsy (typically open baffle or sealed designs) and Betsy K (typically vented designs).
https://www.diyaudio.com/community/threads/betsyk-ml-tl-and-tqwt.182745/
There are lots of quality Betsy and Betsy K designs on the forum…and the drivers are a very good value.
https://www.diyaudio.com/community/threads/betsyk-ml-tl-and-tqwt.182745/
There are lots of quality Betsy and Betsy K designs on the forum…and the drivers are a very good value.
If you look at horn or pro sound type designs, those are typically going to be higher sensitivity. Many have been adapted to home use for this reason, and there are some commercially available designs that are doing similar things.
Heretic AD614
https://www.stereophile.com/content/gramophone-dreams-71-heretic-ad614-loudspeaker
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Lowther is one of the classic full-range high sensitivity options. They have plans/kits as well.
https://www.lowtherloudspeakers.com/
https://www.lowtherloudspeakers.com/
Actually, most speakers are rated at 2,83V, which would be 1W at 8 Ohm. But since there are speakers with the nominal impedance of 2, 4, 6, 8, 16 etc Ohm, you have to calculate how much power the measurement actually is rated. Ie, for 4 Ohm speakers measured with 2,83V, it's actually 2W. Some companies actually give the spl at 1W (ie Monacor usually does that). That means, you have to read very careful when comparing the spl of a speaker.
Aside from that, most drivers have the spl only in some range, cone drivers (to name one kind) usually have the highest spl in the midrange. And you have to keep the baffle step in mind, below that frequency - depending on the baffle dimensions - you lose another few dB.
It is a good driver, it's cheap, sounds good but realistically, you need a (super-) tweeter for it.
I know that's an excellent hearing aid but that might not solve all problems. My dad got very bad hearing, for him there's nothing above 4k. But what's worse, his cognitive recognition declines very rapidly. With his hearing aid he often hears very faint noises and sounds but he often fails to follow a conversation if there appears a turn in the discussion, he can hear it but he can't recognize the words if it doesn't follow what he expect it could be. To give an example (well, the conversation was in German), he was annoyed when he put the sun umbrella/shade into its stand, the metal tube blew out rust particles up in the air because of the air displacement of the umbrella and the fact the stand was constantly standing in the weather. I told him with several paraphrasings that it could be fixed by boring a hole on the bottom of the stand to evacuate the water and the air (with the rust particles too). He never understood the 'dust' part even if I've smiplified the phrasing extremely until I told him loudly "DUST, DIRT, POWDER, CRUMBS, RESIDUE, ASH, PARTICLES, CREMAINS". After that he took a minute (literally) to compute and then said "don't scream at me! I understand". Well, he clearly didn't, even if it was vocally perfectly clear. I don't think that applies to you but if someone's not understanding something, it might not be the actual hearing but the cognitive decline. And that's what worries me, he's already driven on the wrong side of a traffic isle, can't drive anymore in the dark and needs his navi to drive to my house (I'm living here for over 20 years). That's the prototype reciepie for becomming a ghost driver but he's adamant he's an incredibly safe and perfectly capable driver - despite being very jumpy, often unable to decide and having an extremely, shockingly long reaction time (about the same as if I drink 6-8 beers!!!!!).
Sorry for rambling again, just wanted to mention hearing problems aren't only loss in sensitivity or frequency range.
Sorry for rambling again, just wanted to mention hearing problems aren't only loss in sensitivity or frequency range.