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Re: Missile nosecone for a sub box?

Robs Ears

Established Member
Hello again.

Firstly, thanks for all the help and enthusiasm in the initial beer inspired build, it was/is a beast of a thing.

I found that I cant reply to the original thread - Missile nosecone for a sub box? - AVForums.com So Ill try another as I have a problem.

The Mission plate amplifier that I used looks to have died, suspected PSU issue as theres no power light coming on and all connections appear fine.

Do you guys have any advice as to how to check for certain just what has died, or more to the point that the driver is still ok?
Assuming the driver is good, any thoughts on a replacement for the very adjustable Mission plate amp that I used? (It served me well and would be happy to fix it if possible.)

Thanks in advance for any help.

A pic to jog the memory...

222459_6272130059_593925059_198583_1267_n.jpg
 
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HiFiRuss71

Distinguished Member
God bless it - It's back!

It's easy to find out if the driver is okay, just hook it up to a a pair of speaker cables from your stereo/AV amp and see if it plays bass without any untoward mechanical noises.

As for the amp - I suspect that it's not worth repairing, but it may be worth an email to Mission technical/support. I can't remember and all of the piccies have disappeared from the original thread where you had the Mission plate amp mounted, but the BK Electronics plate amps are still good, very robust value...

Russell

PS. If you were doing this now, there's a dedicated DIY sub forum. Apparently some of us were becoming boring to the world in general...:rolleyes:
 

swiftpete

Distinguished Member
You can reply to the original thread, you just need to click the check box at the bottom that says you're aware it's an old thread and still want to reply to it. If you did that then a mod moved it to the DIY section, then everyone that missed it the first time round can see it's awesomeness as this thing is brilliant!
 

Robs Ears

Established Member
Awww, thanks guys! Its a shame that the scrapyard I got it from is no longer on the go.

Thanks for the advice, I was just wary of damaging the sub or an amplifier by testing that way. Ill try it and keep the volume fairly low. The Mission lump was just sitting on a shelf, it never got mounted into anything as I liked it just sitting there all purposeful. Ha.

Ive found the photos on my hard drive and if I can find hosting space for them then Im happy to fix the missing pics, if you really think there would be that much interest. I just dont want to come across all big headed etc...
 

Robs Ears

Established Member
Well the good news is that the driver is fine. I plugged it into my Marantz PM8200 and it surprised me just what higher frequencies it will put out too, given a full frequency signal.

Right, I need suggestions for a suitable, replacement amplifier for sure then. I still know nothing about sub amps Im afraid. It all feels a bit familiar does this...

Ill look at the BK things and check the original thread for the sensible suggestions I didnt listen to back then. Im looking at spending an absolute maximum of £200, less would be better.

The driver fitted is a Peerless 830845, I forgot to mention that and didnt find it in the other thread either. The nosecone is in bits now for a refurb and a bit of a spruce up seeing as its out of action. Any suggestions as to improving the sound or appearance are gratefully received.
 
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Robs Ears

Established Member
It seems that interest is waning.

Come on guys, Ive bought a replacement amplifier! Its a Behringer Europower 2500... that ought to do it.

Flicking through the manual now and I see that it states:

"When using 8 ohm speakers (with the 2500) a power rating of at least 2 x 450W is recommended to assure optimal operation."

I realise the amp is somewhat more than I require, but hey, you never know, I might knock up a second cone if I can find one so Ive covered my back. Seeing as the single driver I have is rated at 8 Ohm, should I just use a single channel rather than bridge the thing? Im thinking thats right, Id just like some reassurance.

I need to buy some cables to suit the mono phono plugged output of my AV amp (Marantz SR7001) to the 1/4" inputs of the Behringer and dont want to get things wrong.

As ever, any advice or comments are welcomed. (Im not too sure what Im doing).
 

HiFiRuss71

Distinguished Member
Sorry - A bit pressed for time at the mo.

Use just one channel and bear in mind that you have more power than you need, although the effect of compressing the air in a sealed sub will help protect the driver. Up to a point.

It's a good choice of amplifier (search the DIY section for methods of suppressing fan noise) for this and future projects. :)

Just bear in mind that if the sub starts to sound a bit hard and stressed, it probably is.

Russell

Sent from my iPhone using AVForums
 

Robs Ears

Established Member
Excellent news. I was hoping this was the case.

Thanks, Ill grab some suitable cables or adapters to suit, I cant see any issues regarding sound output, as you say, plenty in reserve... for now at least.

I must try and find some way of recording its output as a means of feedback for the help Ive had, just to see how it compares to proper gear.

Cheers, I do enjoy this thing scaring the hell out of me. Its been a lot of fun.
 

Robs Ears

Established Member
Thanks again Russ.

I set it all up yesterday and was seriously unimpressed with that fan noise, so today Ive been through the thread you pointed to and have ordered the 24v fan from the first post along with the silicone bits from ebay. :smashin:

The bass is different to before with the Mission plate amp, due I guess to the lack of twiddly nobs that helped with the Mission. Its sounding a bit woolly now, its ok for films, but sloppy/boomy with music, not at all sharp. Dropping the crossover point from the AV amp from 80-60Hz has helped a bit I think but it needs some sort of tuning adjustment as its left a hole in the bass between it and my bookshelf Tangents.
I should add that the now dead Mission was used with a Marantz PM8200 via speaker outputs and now Im using a Marantz SR7001 subwoofer output.

The subwoofer output on the 7001 needing turning up to maximum ie "+12dB" compared to the little old Mordaunt Short MS308 needing just "+4dB". Its plugged in via the same phono lead then a mono phono to 1/4" jack adapter into channel 1. Im pretty sure Ive set the dip switches correctly on the back, but I had to set the gain surprisingly high too. I hope this is normal as the mission plate amp didnt require the volume turning up above 4 of 11.

Apols for the long, noob post, but if anyone can offer any suggestions for improvement or possible reasons for the jump in the settings then Im all ears. Ill fiddle with cables and stuff in the meantime. :confused:
 

Robs Ears

Established Member
ps - If a Moderator/Administrator wouldnt mind moving this to the DIY Subwoofer section, Id be grateful, as I might get a bit more exposure and help over there. :)
 

micb3rd

Established Member
Play some music you know well, then try swapping the phase i.e the + and - at the amp or subwoofer end, then relisten then swap back and relisten.
 

Member 639844

Former Advertiser
Play some music you know well, then try swapping the phase i.e the + and - at the amp or subwoofer end, then relisten then swap back and relisten.

If you do decide to give this a go,

If you can, get someone to help and get them to adjust the phase while you listen, it makes it easier. I also found closing your eyes can help as well.
 

Robs Ears

Established Member
Hi. Im back again with more problems and questions. :hiya:

Ive not got around to playing with this as Ive moved house and had other priorities, but want the beasty back in service now.

Problem -
P1030937%20(Large).JPG


More pics here - Photos in robncarrie's 'MissionPeerless' album

Im wanting to use the sub with a stereo that only has no sub/LFE out, just full frequency line outs and regular speaker outputs (Marantz PM8200), so I need some low pass filtering and control. I still have the EP2500, but no frequency filtering.

So, first off Im trying to get hold of someone at Mission to see if by any chance I can get hold of a replacement board for the one thats fried in my Mission E8AS2 plate amp in the above photo. Ive tried the page here - Mission audio Contact but it wont send my query, the send button appears to be broken.
I suspect Im grasping at straws, but figured its worth a shot to try to get this thing repaired as the nosecone sounded pretty good through it. Does anyone know of an email address to them, preferably within the uk, that works? Or even a phone number?

Failing that, is there a nice, cheap box of tricks that I can use with the EP that would give similar levels of control/EQ as the Mission did? Ive seen the Behringer Feedback Destroyer, but not too sure if thats what I need or would be a good idea at all. Im a bit lost again.

Any help or suggestions greatly appreciated.
 

Member 639844

Former Advertiser
A BFD would be ideal as its a fairly comprehensive PEQ, its 2 channel, and has about 24 filters total IIRC. You will need to learn how to use REW though if you want to get the most from it, but on the plus side, REW can be used to make it an auto eq solution.
 

Robs Ears

Established Member
Thanks, I keep ending up linked to the BFD as I rummage the net for information and advice that I can mostly understand.

Ive just signed up to the Home Theatre Shack, Ill see what I can glean from there while I destroy my womans gin and tonic stock.
 

Robs Ears

Established Member
Hello again.

The nosecone is undergoing a refurb at the mo, no new news in regard to that other than a 60mm thick steel baffle plate that keeps it well and truly nailed down as it weighs a ton now.

Thought Id pop in and say hi and wonder what you guys would think if perhaps Id found another nosecone, but bigger. Around 1m tall and 0.5m diameter and at a rough guess about double the volume, so around 80-90 litres as a rough guess and made out of aluminium this time.
I have a spare channel on the Europower EP2500 as well as the Behringer FBD and crossover... Its asking for it isnt it?

But what magnet backed, cone shaped thing to fit in it in order to create obscene frequencies? Would this fall into the realm of 18" transducers?
Any thoughts on the aluminium construction? Id be looking at another serious steel baffle plate for it, thats for sure.
Any considerations to resonance/deadening/sound proofing?


Beer is flowing well, so hit me with your dirtiest thoughts. So to speak. If this is a realistic proposition then it will be going opposite the existing stupid cone in a brand spanking cinema room, it needs to be made to work.

Just realised all the pics have gone, so heres a reminder of the original daftness -

317533_10150264954845060_4099835_n.jpg


And the baffle plate -

309892_10150270687130060_299691947_n.jpg
 
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scottthehat

Distinguished Member
Yeah man that would make a nice df sub, mount some feet line the inside.
 

Robs Ears

Established Member
Ah, I guess you mean the one pictured? That has feet and is up and running. Its getting lined with some damping material just to see what happens and the baffle seal replaced as I found a leak.

Whats df?

My query was for a larger, similar type of enclosure though, not the one shown above. Basically, I need a driver to suit around 80-90 litres in a sealed enclosure with a claimed 1200W @ 2 Ohms available for it from the EP2500 no idea what something rated at 4 Ohms would get, but I cant imagine its to be sniffed at. Im clueless re a driver, any thoughts?
 

scottthehat

Distinguished Member
Sorry can't see pictures properly on my phone.
Drives wise look at the likes of a fi q .
 

mojogoes

Remembered (1961-2016)
A BFD would be ideal as its a fairly comprehensive PEQ, its 2 channel, and has about 24 filters total IIRC. You will need to learn how to use REW though if you want to get the most from it, but on the plus side, REW can be used to make it an auto eq solution.


Moonfly i have the latest REW version on my computer but in the respect of hardware that's needed now in caparison to 5/6 years ago how does it differ compared in order to get adequate readings etc than what you needed back then..........i've heard that you can connect your mic straight to the computer via usb with out having to have a phantom voltage line in etc.
 

Member 639844

Former Advertiser
Moonfly is no longer active :)

If your laptop has a suitable line in port, then all you need is a compatible meter (or an expensive calibrated one) and your good to go. Some machines seem more problematic than others to get them running well with REW though.
 
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