Hi !
Now i finally moved my empeg from car to home and he shound stay here ;-)

Some time ago i have seen some nice cases and home installs of the empeg. I have also seen a nice case made of wood. Now i can't found the pictures. Can u help me ? Post pictures of home installs here. Thx and greetings from snowy poland.

You're probably thinking of Mark Lords docking stations (at least for the wooden ones). Click the "Home Docks" link at the top of the page.

That one has only been made (currently no longer produced) for the MKII(a), which has a different connector/sled compared to the MkI (which you, according to your signature, have).

A number of users have produced one-offs in various materials.

I think your best bet is finding someone local that is handy (unless you meet that criteria yourself ) that can put together a box, in whatever material you favor, that houses the MkI docking sled you have (and, as you say it'll stay in the house, don't need in order to mount it in the car). That makes the whole project fairly easy - or you can get the fitting connector
and build something like Marks docking station, but that fits the MkI. Info on where to find them, as well as pin-out can be found here

/Michael

My docking station thread was posted in the Installation section. You can also find pictures of home docks on riocar.org's gallery section. Tony Fabris made a dock out of wood, too, and several people have converted PC cases or other electronic enclosures to docking stations.

Many thanx, with your help i found many interesting photos. I have choosen some and give them with the sleed to a person who i think he can do a nice case for me www . I will post the results and pics here when it's ready.

I think the time is already coming, where our empegs can be moved home and rest here to be old ;-)

The home for my empeg is done....








Inside is empeg MK1, pioneer 2x30W amplifier, stereo volume potentiometer, switching power supply 60W, 2x10cm magnat 2way speaker.

Feel free to post comments.

It's a thing of true beauty. So, you've got the empeg as well as amplification in there? Does it have a cooling fan as well?

Yes yes. I have a fan inside the empeg. The amplification and power supply does not go warm after an hour of operation at 3/4 volume. I an open back at this time, but a back is coming, with many holes and a big fan slowed down as possible. Between the amplifier and the empeg is the volume potentiometer (50k).

I'm really proud of this

Stunning! An excellent all-in-one solution, and original too. Love it.

that is most impressive.

Very nice work!

Wow, that is good work! It looks like something out of a very high end audio store.

Hi PKi

What you need to do is use reflex ports for your forced-air cooling. For example, one port near each speaker and a fan mounted internally in the centre, blowing air from one end to the other. You probably also want to make a circuit to mono-ise the low frequencies so the drivers aren't fighting each other down there (or get someone to add it to hijack).

I can calculate port lengths for you if you supply box dimensions (internal, minus space used up by amp etc) and driver specs. I've been known to dabble in speakers (deafened my first Broadcom colleague yesterday).

Cheers, John

Oh great. I asked several people to calculate it, but nobody helped me.

The dimensions in cm are: 34x22x14 (internal). The speakers are 10cm. Minus empeg, amplifier (15x15x2,5), psu (12x6x3).

The back panel is about 1cm deeper, have no picture of it now.
The amplifier is in the middle under the empeg. I have put some damping material on top and bottom and between empeg and speakers. The psu is now between a speaker and empeg but i will put it in the middle top.

If i think right the circuit should mix together both channels on low frequency? Can u give a schematic?

Hi

For designing the ports, I need the full specs for the drivers - if they have a model number written on them then try that in google or on Magnat's web site. I need numbers like Fs, Qts, Vas etc. Will suppliy the other info tomorrow.

Cheers, John

Ohhh. I dont think i can get all this parameters.
Its Magnat Ultra 102, here is the manual:
http://www.magnat.de/download/BDA111402.pdf

Try to use a 10cm speaker you know and you think can be similar to the magnats.

PKi, that's beautiful!

One unrelated question - what's that indicator on the screen of your empeg in the upper right hand corner? I've not seen that before...

- Jon

It's the disk access indicator. Shows operation on the HDD.

Hi

Well, I tried Alpine, Pioneer and Sony - Alpine and Sony have similar drivers but no specs. So, time for some "engineering expediency". Freq range is given as 62-21000Hz, so I will assume that 62Hz is the Fs. Typical Vas for a 6 inch driver is about 1 cubic foot. Assuming the same mech compliance, that gives us 7 litres for the 4 inch.

Your internal volume comes to about 8 litres, which must be split across 2 drivers so it's effectively 4 litres per driver.

Now, a common rule of thumb for reflex tuning if you don't have all the info is to go for the driver Fs, in this case 62Hz. However, porting only helps if the enclosure is not too resonant to start with. I can't guess the driver's Qts and this is hard to measure.

If the drivers without porting sound thin with some tight but not very loud bass (in sealed cabinet), then they probably have a low enough Qts to be suitable for porting - in which case port at 62 Hz and enjoy louder bass.

On the other hand, if the drivers sound like they have quite full bass already (but not very deep) then they are not suitable for porting. However, you want the ports anyway for airflow reasons - a compromise in this case would be to "underport" where you tune too low, and the port has little acoustic effect, but can still pass a DC airflow. Underporting would require about 30Hz tuning freq in this case.

A simple formula for port length is (from memory) Ld = 2691 * Sd / Vb / Fb^2 - 0.88 sqrt(Sd). It's all in feet and inches I'm afraid. Your Vb (for each driver) is therefore 1/7. Trying a 1 inch port (Sd=pi/4) and Fb=62 Hz, we get Ld = 3.07 inches.

If the driver is suitable for porting then based on what I know, I recommend a 1 inch diameter, 3 inch long port for each driver. If not, I recommend you use ports 1 inch diameter and 12 inches long to underport down to about 30Hz.

In order to mono-ise the bass, I suggest something like this:

Code:

---

empeg L ---/\/\/\/-----+------ amp L
                       |
                     -----
                     -----
                       |
empeg R ---/\/\/\/-----+------ amp R

---

I.e. run the empeg's L and R outputs through resistors and then join them to each other via a cpacitor. You need to determine the amp's input imedance (should be in the specs) and use resistors of about the same value (R). The cap is then 1/(5000R) for a 300Hz cut-over (roughly). I choose 300 Hz becuse the driver seperation is about a quarter-wave at 300Hz, and so that's about where the drivers begin to act as a point source acoustically.

Now all you have to do is install the fan in the middle of the box - you should be able to build a partial baffle across the middle of the box to assist the airflow. No need to seal it from an acousticl POV becuase there will be negligable sound pressure across it.

Anyway, I hope this helps even though its all a bit vague and approximate. Do try experimenting. You could also try mailing Magnat for the driver specs just on the offchance. I'll probably not log in until next year now, so speak to you then.

Cheers, John

Edit: fixed ASCII art -wfaulk

Obviously lots of spaces have disappeared from my ASCII art - the cap is meant to be further to the right, aligned with the + signs.

This board obviously thinks I just press the space bar for a cheap thrill, or the lulz, or something.

Fixed that for you.

Great work on the dock/speaker box. And with JohnnyGee's tips, you'll soon be putting Bose to shame. Good work.

So the capacitor in my diagram is wrong - it needs to be an inductor instead. It's hard to find inductors with the sort of value you will need (and they will typically have metal cores which will mess with sound quality).

Other options include an active circuit (which uses an op-amp and needs a power supply) or some aoftware running on the car player courtesy of Hijack. I can write the algorithm for you but I wouldn't know how to integrate it into Hijack - let me know if you're interested.

In the meantime you are better off leaving out the mono-ise circuit and connecting directly. things will only go wierd in tracks whoose bass is panned signficantly, which is a minority of cases.

Cheers, John