Doing some research on this, and the only thing I’ve seen that I didn’t see mentioned, was also looking at the speakers Excursion as well. The relationship between the PR and the driver are equal importance. Besides that, I have all the info I need now I know about the F3 to enclosure volume relation. Thanks!
Hey Toid, can you give us a quick rundown on what the problem is if the tuning frequency is not near the F3? You made it sound like that its an issue. Also, is this for all types of enclosures or only for passive radiator?
I'm running two Dayton Audio Epique 7" Subs and two Epique 5.5" PR's, No matter how much I change the box volume, the tuning frequency is always too low to match the f3 frequency. Is there any way to fix that?
I’m not sure what you mean. But one thing I will say for sure is that two 5 1/2 inch passive radiators for two 7 inch subs is not going to work well. You typically want two times the volume displacement. In this case you would want four 7 inch passive radiators. Of course, that’s the assumption without actually running the calculations.
thank you, please I have a 30w, 8ohm speaker. that's the only 2 data I read on the emant. how I can calculate the air of my box (speaker) to be made using winISD?
Just a question so if I get a passionate radiator it doesn't have the specs from EBay What if I use the specs from a One of the other ones is about the same size wouldn't that be pretty close
A little late to the party but I was watching your video and had a question. I am trying to tune the frequency by adjusting the box volume, like in your video, but I can't seem to get the -3db frequency to be anywhere near the box frequency. What does that mean? I am using a 6.5" woofer with a 8" PR. I can provide more details if you want. Also shout out to Kirby Meets Audio. Would've never found you without him.
What do you mean by box fequency? Are you saying you are not getting the -3 anywhere near tuning? If so, that could mean a couple things. But the immediate thing it means is you need to raise your tuning frequency. Try changing your box size and your weights on the passive radiator to see what happens.
Hey, do i have to type in "added mass" the moving mass + the added mass? because winISD just ask about qms , cd etc and not the moving mass of the PR. If I type in mms + additional weight the tuning freq of the pr makes much more sense. Thanks
Im building a sealed box for 4 15s and i wanna add some passive radiators (either some pump 12s or some slaps 15s from earthquake sound). A proper sealed box would be 10 cubes but if i make it 8 cubes could i still use the PRs to get it to play low ? Subs only have an xmax of 14mm ( Q power suoer deluxe 15)
Just a quick update. I am making a Passive Radiator sub. It should be up next week. So if you want to see it, make sure your subscribed. I'll leave a build log and parts list.
Hi! First a big thanks for all your vids. They are rly helpful! Meanwhile I understand the basics like entering the T/S datas and what they all mean. But I don`t understand the whole Transfer function magnitude topic. First, what do the -3db point and 0db mean? Second, why should the tuning frequency be the same as the f3? And why are there db an hz? What do they have in common? Like when you give the speaker an input signal of about two watts it results in a graph. The graph does always show that the lower frequencies are much quieter, but why? There`s a huge gap between the lower and higher frequencies in relation to the loudness. Thanks in advance for your answer!
That is a lot of questions, lol. Let's see if we can clear them up for you. First, the 0 and -3db. The -3db is considered a speakers F3. This is the frequency where a speaker is typically 3db down from it's normal spl. This is where most people focus on, as after this you start to lose a lot of the spl past this. Secondly, he tuning frequency does not need to be the f3. However, you do need to make sure you are not tuning well below the f3. If you are you will have issues, most likely with cone excursion and resonate frequency. So it should be near, but not right at. Finally, it is much harder for an amplifier to power lower frequencies. If you take a look at individual speaker parts you will notice a spec called sensitivity. In easy terms, this relates to how much wattage a speaker needs to be driven to the same sound level as other speakers in the system. What you will notice, is that woofers and subwoofers will have a much lower sensitivity than say a tweeter. You see it takes, a lot more power to drive those speakers lower. You'll also start seeing a correlation between even the woofers. The less sensitive ones, can often have lower tuning frequencies. As far as the gap between higher and lower frequencies, that is what an L-pad is for. You use an L-pad to attenuate your tweeter to match the sensitivity of your woofer or midrange
Yeah, I know;) So, a L-pad is like a crossover? That matches that the bass has the same loundness as the tweeter.. And the F3 seems to be rly important.. Could I say that when the F3 is very low (40hz) a lot of people would say that the bass is very deep? And everything below the F3 isn`t very noticeable anymore.. ? Your a really helpful guy! Thx
A L-pad isn't a crossover, it is a filter used in a crossover. It is used to match the sensitivity of the lowest sensitive speaker, so one speaker does not play louder than the others. It is typically used on a tweeter in a two way system. The last think you want is for the tweeter to overpower you. As far as the f3 goes, most mainstream music doesn't play past 60hz. SO if you are looking for a musical speaker, an f3 of 60 is pretty good. However if you are looking at movies, you would like to have an f3 of 40 or lower. The 30hz and under range is more felt than heard. So you need bigger speakers really to reproduce those in a meaningful way. As far, as not noticeable, I guess that is one way to put it. However, we are not taking into account room dynamics. You room can actually boost or deaden certain frequencies. Having said that, you will hardly notice anything past f16. From f15-f3 you will still notice, but not nearly as much as something at 0 or f3. Basically, your speakers will probably overpower those frequencies. SO even though, they are present, they won't be heard as much.
Just a quick update. I am making a Passive Radiator sub. It should be up next week. So if you want to see it, make sure your subscribed. I'll leave a build log and parts list.
I really don't know a good way. You would end up needing some measurement equipment along with some trial and error. I would start with around the same size as a ported enclosure. Then continue to add weight to the passive radiators until you get your desired result.
yes parts express allows you to download that for free from their site. If you need to know how to input data and exactly where to get it, check out this video for detailed information. ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-Ol7K5wQrFAg.html
There is no way, that I know of. If you have a microphone like the umik1, you can use REW, to get a baseline in the enclosure you are using. Then adjust with weight and enclosure size as needed. It's a lot more work, but it's one of the only ways I know of. This is one of the reasons I try to steer away from Ebay when buying passive radiators. But you usually can't beat the price!
123Toid Thanks for your answer. I bought the PR on ebay because I couldn't find any with a diameter of arrourd 1.5". Do you know any seller that sells small PR with a datasheet? I can't find anyway to design my enclosure on winisd without theses specs.
+Pierre Dal Busco Typically you won't find much below about 3.5" with specs. Mainly, this is due to you needing about double the air movement of your passive radiator compared to your speakers. So a 1.5" passive radiator would typically pair with around a 3/4" speaker l. and that type of speaker will not get very low. However, you may be able to find some small passive radiators that will work. I'd check out Ali Express. If the specs aren't listed, sellers will often get them for you. You will have to email the seller though. I hope this helps.
Just a quick update. I am making a Passive Radiator sub. It should be up next week. So if you want to see it, make sure your subscribed. I'll leave a build log and parts list.
the reason for this is, you can't tune a sealed box. You can only tune a ported enclosure. With a sealed box all you do is change the size of the box and that will change the response.
Thanks man! I was losing it because I thought something was wrong with the program LOL. About to watch your passive radiator video again. Any reason why you didn’t use one 8” driver with 10” passives or like one 10” with 12” passives?
@@Toid One last quick question: In this video, you only modeled 1 driver and one passive radiator, but when you did the build, you had two passive radiators. Should the model in WinISD have had 2 passive radiators to equal the build? Just making sure I'm entering the data right. I'm getting really a really high f3.
No you don't. But since this video, I have actually switched to the altest version. That version is available for download from their facebook page. Just google winisd facebook.
I understand how a PR works, and how to tune it, but what I'm wondering is what the optimal box internal volume is when using a PR? Should it be about the same size as if the box were designed to be closed? Thx.
Bob Richards that's all explained in the video. assuming you have the specs, the program will help you adjust both the box size and added mass hat will get you the response you are attempting to get. BUt in short, the answer is no.
Just a quick update. I am making a Passive Radiator sub. It should be up next week. So if you want to see it, make sure your subscribed. I'll leave a build log and parts list.
