Speakerplans.com Homepage
Forum Home Forum Home > Plans > New Projects Forum
  New Posts New Posts RSS Feed - Lockdown Audio - A 12v 3way Small Rig Build
  FAQ FAQ  Forum Search   Events   Register Register  Login Login

Lockdown Audio - A 12v 3way Small Rig Build

 Post Reply Post Reply Page  123 14>
Author
Message Reverse Sort Order
 Rating: Topic Rating: 1 Votes, Average 5.00  Topic Search Topic Search  Topic Options Topic Options
Jack1991 View Drop Down
Registered User
Registered User


Joined: 05 February 2020
Status: Offline
Points: 406
Post Options Post Options   Thanks (0) Thanks(0)   Quote Jack1991 Quote  Post ReplyReply Direct Link To This Post Topic: Lockdown Audio - A 12v 3way Small Rig Build
    Posted: 14 May 2022 at 3:13pm
Cool cheers man thats good to know for future. Ill have a proper look at them later when home.

Nice thats good ill test it out aswell see how it sounds with the port blocked. Ill see how it looks on winisd too or would the results not match real life?
Back to Top
infrasound View Drop Down
Old Croc
Old Croc


Joined: 13 May 2011
Location: Brizzle
Status: Offline
Points: 2259
Post Options Post Options   Thanks (0) Thanks(0)   Quote infrasound Quote  Post ReplyReply Direct Link To This Post Posted: 14 May 2022 at 3:03pm
Doesn’t have to be anything special, socks or jumpers work for blocking the port. 
Back to Top
Lucasdude View Drop Down
Registered User
Registered User


Joined: 16 March 2013
Location: London
Status: Offline
Points: 487
Post Options Post Options   Thanks (0) Thanks(0)   Quote Lucasdude Quote  Post ReplyReply Direct Link To This Post Posted: 14 May 2022 at 12:56pm
I'm only suggesting you consider an automotive solution because its likely to work better on a wider input voltage range like your car amps, can be used standalone, has more outputs and can provide a higher voltage output.
Fyi, the same company does a range of chargers/DC psus which I've found quite interesting. A 12v system is great until it runs out of juice and those products can power a lot of amps and charge multiple batteries simultaneously.


Edited by Lucasdude - 14 May 2022 at 12:59pm
Back to Top
Jack1991 View Drop Down
Registered User
Registered User


Joined: 05 February 2020
Status: Offline
Points: 406
Post Options Post Options   Thanks (0) Thanks(0)   Quote Jack1991 Quote  Post ReplyReply Direct Link To This Post Posted: 14 May 2022 at 12:46pm
Yeh id be lost without this forum, i couldnt of done anything just from a book haha. Fairplay for doing so though!

Ah yeh i will give that a go too with trying it sealed. I guess i can just bung something tight in the port to test it out to see if it like it before commiting?

I have a dsp the t.racks one seems real good. I guess that one in the link seems similar?
This one:




Edited by Jack1991 - 14 May 2022 at 12:47pm
Back to Top
Lucasdude View Drop Down
Registered User
Registered User


Joined: 16 March 2013
Location: London
Status: Offline
Points: 487
Post Options Post Options   Thanks (0) Thanks(0)   Quote Lucasdude Quote  Post ReplyReply Direct Link To This Post Posted: 14 May 2022 at 11:53am
I remember a friend of mine making a similar cabinet in the early 90s. All we had to go on back then was a "Loudspeaker Design and Construction" by Eminence.... Anyway, he wanted to add a little more flexibility by porting it like yours, but he added a thread to the pipe and capped it so it could be used as sealed or reflex. I can't remember if I ever listened to the difference, but as someone else said you might be better off trying that cab sealed with some eq to the bandpass.


I've been meaning to try out what Brazil can bring to the party myself, but it might work for you!


Edited by Lucasdude - 14 May 2022 at 12:03pm
Back to Top
Jack1991 View Drop Down
Registered User
Registered User


Joined: 05 February 2020
Status: Offline
Points: 406
Post Options Post Options   Thanks (0) Thanks(0)   Quote Jack1991 Quote  Post ReplyReply Direct Link To This Post Posted: 14 May 2022 at 11:41am
Couple little changes. Took out all the egg foam stuffing and fitted a few pieces of dacron stuffing to the middle of opposing walls like suggested.



Added foam gasket to the drivers.



And changed the old bolts to stainless steel. As the old bolts were just standard black ones and had started to show signs of rust. 



Will test it out soon and see if it sounds any better like that. Thanks again for your help people.
Back to Top
Bams View Drop Down
Young Croc
Young Croc


Joined: 08 April 2009
Status: Offline
Points: 553
Post Options Post Options   Thanks (0) Thanks(0)   Quote Bams Quote  Post ReplyReply Direct Link To This Post Posted: 06 May 2022 at 9:30pm
In my experience non-discerning listeners tend to “forget” the major impact of a decent mid-section and therefore also will say something sounds gold faster than when you are listening critical. Therefore.. trust only your own ears.
Back to Top
Jack1991 View Drop Down
Registered User
Registered User


Joined: 05 February 2020
Status: Offline
Points: 406
Post Options Post Options   Thanks (0) Thanks(0)   Quote Jack1991 Quote  Post ReplyReply Direct Link To This Post Posted: 06 May 2022 at 8:37pm








If there is any other particular bits on winisd i should post let me know and ill get them 🙂👍🏼






Edited by Jack1991 - 06 May 2022 at 8:45pm
Back to Top
Jack1991 View Drop Down
Registered User
Registered User


Joined: 05 February 2020
Status: Offline
Points: 406
Post Options Post Options   Thanks (0) Thanks(0)   Quote Jack1991 Quote  Post ReplyReply Direct Link To This Post Posted: 06 May 2022 at 8:24pm
Fatfreddiescat:
Ah ok i see thanks man. As for the baffle step compensation that is something i havent heard of before so will get reading up on that to try understand it.


toastyghost:
Oh yeh only just noticed myself too i didnt post my winisd results. I will get them now from my laptop and share them on a seperate post. For the mids I have 2 seperate chambers, volume of each chamber is  23L  1x round port per chamber 10cm wide by 11.5cm long. Tuned to 73.50hz.

Im not quite sure what you mean on the second paragraph its a bit out of my depth of knowledge. And also as far as i know i didnt account for port end correction, something i havent heard of before either. Thats good to know about the stuffing too, i do feel as if it sounds a bit too stuffed, although as a newbie im not 100% sure, it just sounds a bit 'softer'.

I remember when i was learning winisd to make the mids, I assumed and was told that it was right to make the tuning freqeuncy as low as it goes with as flat a line, as i would be crossing over at around 100hz anyway so anything below wouldnt be used through the mids.

I should have also said previously too, when i took out just 2 thams, the mids and tops a couple years ago, before i had the dsp, so i was only using the amplifiers built in crossovers, and no delay etc. I didnt notice the mids sounding not quite right. To me then it all sounded perfect. So wether i have just got a better ear for it now, or something i am setting wrong in the dsp isnt quite right maybe, im not sure.


On the DSP i have only set delay and the crossovers.

Delay:
Mids and Tops delayed by 5.9ms, as i worked out tham horn length to that.

Crossovers all LK 24 
Thams 20hz - 100hz
Mids 100hz - 2000hz
Tops 2000hz - 20,000hz




Edited by Jack1991 - 06 May 2022 at 8:30pm
Back to Top
toastyghost View Drop Down
The 10,000 Points Club
The 10,000 Points Club
Avatar

Joined: 09 January 2007
Location: Manchester
Status: Offline
Points: 10703
Post Options Post Options   Thanks (0) Thanks(0)   Quote toastyghost Quote  Post ReplyReply Direct Link To This Post Posted: 06 May 2022 at 4:36pm
I just skipped back a bunch but couldn’t see anywhere that you showed your WinISD plots / settings, or the cabinet dimensions for your mids. Can you share those?

You might find that the time of flight around the cabinet for your port’s output is arriving out of time with the same pass band from the front of the driver. If you have the cabinet dimensions, then you can calculate the time offset. A port’s output is anti phase to the diaphragm regardless - a polarity inversion and extra time delay is basically a principle of cardioid subwoofer setups for cancellation at the rear.

If you have that the wrong way round physically, the cancellation might be happening at the front instead. Hard to tell even stood at the rear of the mid box, because the directivity of the diaphragm output means you won’t hear the upper region anyway.

Also, did you account for port end correction in the model?

I can’t remember if it’s enabled in WinISD by default, but a port’s length generally needs to be adjusted from what the simple models say to achieve the desired tuning. The amount of end correction changes based on port dimensions and shape. Some software such as Tolvan Basta! has a check box to calculate a length correction factor, but even then there’s often some fudging needed based on measurements.

The reason I ask is that you may find the box is currently tuned too low. A friend did that recently on an 8” coaxial box - calculated the port to 67Hz but ended up under 50Hz which was so far in the roll off that it sounded thin. It’s easily done.

Adding lots of stuffing will make the box appear bigger acoustically at some frequencies too, so it might be making the problem worse.
Back to Top
fatfreddiescat View Drop Down
Young Croc
Young Croc
Avatar

Joined: 15 October 2010
Location: N.E.Wales
Status: Offline
Points: 957
Post Options Post Options   Thanks (0) Thanks(0)   Quote fatfreddiescat Quote  Post ReplyReply Direct Link To This Post Posted: 06 May 2022 at 2:22pm
Really need to check the acoustic response of the xover area to make sure their in phase either side of it and working as expected, also the top box will likley want some baffle step compensation as will be transitioning from 4pi to 2pi loading ish.
Back to Top
Jack1991 View Drop Down
Registered User
Registered User


Joined: 05 February 2020
Status: Offline
Points: 406
Post Options Post Options   Thanks (0) Thanks(0)   Quote Jack1991 Quote  Post ReplyReply Direct Link To This Post Posted: 06 May 2022 at 12:20pm
Cool that sounds good ill give it a go. What do you reccomend to block the ports up with? Id like to do it temporary first just incase. Also yeh i have got dacron at home now too, recently got it for another project.

The software for the dsp on the EQ page looks like that in photo (photo off their website as im not home) Not sure if its possible without seeing measurements but do you have any suggestions for what to set the eq for the mids? Id like to learn how to measure it all & be able to test lots of things out, but i dont have the knowledge or space to do it.





Edited by Jack1991 - 06 May 2022 at 12:20pm
Back to Top
 Post Reply Post Reply Page  123 14>

Forum Jump Forum Permissions View Drop Down

Forum Software by Web Wiz Forums® version 12.05
Copyright ©2001-2022 Web Wiz Ltd.

This page was generated in 0.080 seconds.