Notch filter for Oris 150/AER MD3? (BD-Design)

by GC, Saturday, April 02, 2005, 12:10 (4674 days ago)

Dear Bert,

I really enjoy my Oris 150/AER MD3 combo! However, on certain recordings some freqencies in the treble seem almost to “drill” in my ears. For instance, this is the case when I listen to Pink Floyd’s “What do you want from me” from the Division Bell album. Here the beautiful lead guitar notes from Gilmour seem to be played at to high volume relative to the other instruments.

Am I hearing “beaming” or ?

I use the Crowns and have tried to listen “off axis”, but the problem is still there.

If I understand it correctly, then I could try a Notch filter. In one post you give the following example of such a filter.

http://www.bd-design.nl/forum/index.php?id=9350

However, I believe this filter was made for the Oris 200/AER MD3. Before I buy the parts, I would like to hear whether this filter is also appropriate for my Oris 150/AER MD 3 combo, or would you suggest something else?

I thank you a lot in anticipation and look forward to hear from you!

Regards
Peter Krojgaard

Tags:
0

Notch filter for Oris 150/AER MD3?

by GC, Saturday, April 02, 2005, 14:31 (4674 days ago) @ GC

Hi Peter,

Its appropiate for the AER MD2 and the AER MD3 drivers regardless which Oris horn is used.

Ciao,

Bert

Tags:
0

Notch filter for Oris 150/AER MD3?

by GC, Saturday, April 02, 2005, 17:04 (4673 days ago) @ GC

Dear Bert,

Thanks a lot for you reply!

- I what I hear related to the phenomenon called "beaming"?

- In the diagram referred to above, the value of the resistor is between 15 and 39 Ohms. What happens to the Notch filter when you use a 15 or a 39 Ohm resistor respectively?

Thanks again!

Regards
Peter

Tags:
0

Notch filter for Oris 150/AER MD3?

by GC, Saturday, April 02, 2005, 17:27 (4673 days ago) @ GC

Hi Peter,

- I what I hear related to the phenomenon called "beaming"?

No, depending on the system its related to a combination of the horn, plugs and driver which gives more or less the effect you decribed. The resistor value reduces the effect more or less. 39 ohms gives maximum effect but also takes away some "life" from the music. Some systems and their owners like this most, others prefer less effect. I use 18 ohms within my system, some prefer even lower values for the resistor.

Use the value (between 15-39 ohm) you like best.

Ciao,

Bert

Tags:
0

Thanks a lot Bert! (nt)

by GC, Saturday, April 02, 2005, 18:46 (4673 days ago) @ GC

Regards
Peter

Tags:
0

Notch filter for Oris 150/AER MD3?

by GC, Sunday, April 03, 2005, 10:34 (4673 days ago) @ GC

Dear Bert!

I was to quick with the "thanks" reply - I must admit that I still have some questions, that I hope you will respond to!

1. It is easy to hit the exact values for the resistors and the capacitors. However, I find it somewhat difficult to reach the exact value of the coil (0.0825 mH). I have the formula to combine coils in parallel, but have trouble getting to exactly 0.0825 mH.

You don't happen to have a combination of coils that leads to the sought for value?


2. I have looked at both Jensen and Mundorf caps. Do you have a preference yourself?

Thanks again, Bert!


Regards
Peter

Tags:
0

Notch filter for Oris 150/AER MD3?

by GC, Sunday, April 03, 2005, 11:53 (4673 days ago) @ GC

Hi Peter,

1. It is easy to hit the exact values for the resistors and the
capacitors. However, I find it somewhat difficult to reach the exact value
of the coil (0.0825 mH). I have the formula to combine coils in parallel,
but have trouble getting to exactly 0.0825 mH.

You don't happen to have a combination of coils that leads to the sought
for value?

I simply unwind a 0.1mH coil until I measure 0.0825mH. One thing to think about is that a coil close to metal will increase the value, the same happens when two coils are close to each other. You think that with two 1mH coils in series that you'll have 2mH.... too close in a specific way could result in a value of 3mH!

Once you have the right coil then make sure to keep it away from metal (unless the coil was wound for such place...)

2. I have looked at both Jensen and Mundorf caps. Do you have a preference
yourself?

I use IT (Inter Technic) paper/oil capacitors. Very clean and smooth sounding without loosing details. Expensive though...

Which type you should use depends on your taste, budget and electronics, same for the resistor and coil...

Ciao,

Bert

Tags:
0

Thanks again, Bert! (nt)

by GC, Sunday, April 03, 2005, 12:59 (4673 days ago) @ GC

Regards
Peter

Tags:
0

RSS Feed of thread