Magnepan MG-20 attenuation & tips

Hello,

I never use attenuation before nor any idea about it, I know should perfome through insertion a non-inductive resistor, what i would like to know how attenuation look like? Is the one come with MG-20 accesserios that look gray and very small piece: width 2 inch, hight and depth half inch, and have two long solid thin metals about 1 and half inch long?

And any other tips for MG-20 to improve the sound?

Anyone care to answer,
Many thanks to all.

Adding the resistors to the tweeters will lower the tweeter level by a couple of dB. Will it be an improvement? Well, that depends on your room, your ears and other factors.

If you think the sound is too bright, lowering the tweeter level will be an improvement. With your room width your Maggy's are probably close to the side walls. Placing some sound absorbing panels at the first reflection points on the side walls may be what you need to do. This is a tweak that always helps.

If your floor is hardwood, tile or another reflective material, carpeting or strategically placed throw rugs would be very helpful. The first reflection point is most important

Thank you JoeE SP9 very for reply and helpful information's. I installed the attenuations and found the sound much better, in beginnings i was afraid because i don't know how they look but i figure out the small rectangular two piece.

Yes i will try some absorbents on the side walls, i know planer are critical about reflections but i will try a thin absorbents like curtains or cotton cloth. before i tried fabric all the sides wall but i lost micro dynamics and upper bass.

My 2 cents is that you might be better off ditching the attenuators and using rf chokes instead.

They are cheap enough to try and really work. The mag ribbons can act as radio antennas and rf can get back to the amp and create some brightness.

Here is some info from the guy who figured it out and implemented it on his mg20s:
http://db.audioasylum.com/mhtml/m.ht...rchtext%3D12e1

If you could post a basic diagram of your room with a description of the furnishings I could give more specific advice.
To find the first reflection points have another person move a mirror along a side wall while you are seated in the "sweet spot". When you can see the speaker on that side in the mirror you have found a first reflection point.
I have 2' x 4' x 3" DIY traps at the first reflection point on my side walls. There are more traps in the room including round bass traps.
Making your own traps is quite easy. Manly Stanley started a thread about his DIY room treatments. He proves that "acoustic treatment" doesn't have to mean agricultural design and utilitarian looks

His look better than mine. I'm quite jealous.:incazzato: :biggrin5:

MS, you have shamed and inspired me. My spring project will be to follow your lead and make mine look better.

Thank you all for wonderful posts. Can i find these chokes online? And anybody try Cardas attenuators? I heard they improve the sound better.

Thanks to all.
:)

Quote:

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Originally Posted by K-High-Fi

Thank you all for wonderful posts. Can i find these chokes online? And anybody try Cardas attenuators? I heard they improve the sound better.

Thanks to all.
:)

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http://www.mouser.com/ProductDetail/...%252bOcg%3d%3d

Hello Every body,

Folks I may need little more help.

I'm just wondering, is inserting 1 Ohm non-inductive degrade the sound or harm the speaker or amp in any way?

And can I attenuate the tweeter and use a absorbents at reflection points at the same time? I was thinking if I attenuate the tweeter I don't need acoustic treatment.

On other way, is using absorbents are much better than attenuations?

Anyone care to answer.
Thanks to all.

Quote:

---

Originally Posted by K-High-Fi

Hello Every body,

Folks I may need little more help.

I'm just wondering, is inserting 1 Ohm non-inductive degrade the sound or harm the speaker or amp in any way?

And can I attenuate the tweeter and use a absorbents at reflection points at the same time? I was thinking if I attenuate the tweeter I don't need acoustic treatment.

On other way, is using absorbents are much better than attenuations?

Anyone care to answer.
Thanks to all.

---

Hello, 'K',

Joe's response back in January '11 is still completely relevant.

No, the resistor will not harm the sound nor harm the speaker, and will reduce the tweeter volume depending on the value of the resistor, (try values in the range of 0.5 to 1.5 ohm).

If reflections are a problem -- which they will be depending on you room and speaker placement -- attenuating the tweeter won't help much. Attenuation and reflection absorption are not mutually exclusive, and both might be useful or necessary.

I listen to a lot of classical music and I find that most recordings sound not-so-good with a "flat" top end. I use a digital equalizer plug-in in my computer music player to gradually roll off response above about 5000 Hz. Neither resistors nor reflection absorption is going to solve this problem that starts with the recordings.

Hi Feanor,
Thank you very much for clarifications. :)

Is equlizer better or necessory?
Please note i avoid it because i thought adding hardweare and connections between source and preamp would add noise.
Any different thoughts!

About chokes, are they safe? and shall i use two chokes in parallel or choke in parallel with a resistor? and how many piece i need?

Also where i can buy non-inductive resistor of different values?

Many thanks.

Quote:

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Originally Posted by K-High-Fi

...
Is equlizer better or necessory?
Please note i avoid it because i thought adding hardweare and connections between source and preamp would add noise.
Any different thoughts! ...

---

K, I was speaking of a digital equalizer in my computer music player -- nowadays I listen to computer files (vs. CDs or LPs) almost exclusively. Personally I wouldn't consider an analog equalizer or an digital equalizer box that sits between source or preamp and amp.

Quote:

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Originally Posted by K-High-Fi

...
About chokes, are they safe? and shall i use two chokes in parallel or choke in parallel with a resistor? and how many piece i need? ...

---

Chokes are safe for quasi-ribbon tweeters if you use appropriate values -- I'm not sure about true ribbons. The purpose of a choke -is to prevent RFI/EMI from feeding back from the tweeter/midrange into your amp. I use one myself although I don't think it makes much of a difference in my case. Use a Bourns 5502-RC which is 10 uH, 9 amps max.

The choke and resistor must be in series; (parallel isn't dangerous but the resistor will have little effect).

Quote:

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Originally Posted by K-High-Fi

...
Also where i can buy non-inductive resistor of different values? ...

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I usually by these sorts of components from Newark.com. Other popular sources are Mouser.com and Digikey.com

Quote:

---

Originally Posted by K-High-Fi

Hello Every body,

Folks I may need little more help.

I'm just wondering, is inserting 1 Ohm non-inductive degrade the sound or harm the speaker or amp in any way?

And can I attenuate the tweeter and use a absorbents at reflection points at the same time? I was thinking if I attenuate the tweeter I don't need acoustic treatment.

On other way, is using absorbents are much better than attenuations?

Anyone care to answer.
Thanks to all.

---

I currently use 1 ohm resistors in my 1.6's and 0.5ohm in my MMG's. If you have concerns about the 20's, give Magnepan a call, they are very helpful. I live about 20 min from the factory and have talked to them personally.

Quote:

---

Originally Posted by K-High-Fi

Hello Every body,

Folks I may need little more help.

I'm just wondering, is inserting 1 Ohm non-inductive degrade the sound or harm the speaker or amp in any way?

And can I attenuate the tweeter and use a absorbents at reflection points at the same time? I was thinking if I attenuate the tweeter I don't need acoustic treatment.

On other way, is using absorbents are much better than attenuations?

Anyone care to answer.
Thanks to all.

---

Yes, you can do both simultaneously. The question is why. Attenuating the tweeters output does nothing other than make the speaker have less treble energy. It does not and can not do anything about problems caused by room acoustics. The only way to fix them is to fix the room.

Fixing the room should be done before upgrading changing or replacing just about anything. It will have a greater effect for the good than almost anything else you can do.

Fix your room. I guarantee you won't be unhappy with the results.

You fix a problem by fixing the cause of the problem not by fixing the symptoms.

Thank you all for very helpfull informations.

Ok how i can tell if my room need to be fixed? And what do i need?

The choke for MG-20 in this link:
5502-RC Bourns | Mouser

Do i need to buy two item for pair of MG-20? And do i need other thing?

If not mistaken, i have to remove non-inductive resister ohm that come with the speaker and instal these Chokes, correct?

Quote:

---

Originally Posted by K-High-Fi

Thank you all for very helpfull informations.

Ok how i can tell if my room need to be fixed? And what do i need?

The choke for MG-20 in this link:
5502-RC Bourns | Mouser

Do i need to buy two item for pair of MG-20? And do i need other thing?

If not mistaken, i have to remove non-inductive resister ohm that come with the speaker and instal these Chokes, correct?

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Personally I won't offer an opinion about whether you need to do anything to your room without knowing how it's set up.

Yes, you could replace the resister with the choke, but the
remember that the two do different things; if you want the attenuation you get from the resistor, you will need to keep it, installed in series with the choke.

Quote:

---

Originally Posted by K-High-Fi

Thank you all for very helpfull informations.

Ok how i can tell if my room need to be fixed? And what do i need?

The choke for MG-20 in this link:
5502-RC Bourns | Mouser

Do i need to buy two item for pair of MG-20? And do i need other thing?

If not mistaken, i have to remove non-inductive resister ohm that come with the speaker and instal these Chokes, correct?

---

IME every room can use some treatment, how much depends on many variables. You can't go wrong with a bass trap in each corner, absorbing panels at the first reflection points and a carpet on the floor. This is enough for many rooms.

Too much absorbing will suck the life out of the music.

I wouuld add a choke only if I was in an RF rich environment, such as, close to an antenna farm or having a ham radio operator or CB'r close by. For most situations RFI is a non-issue.

Thank you all very much for your help.

I understand all.

Please can anyone show me the link for non-inductive resistors ( in series) which can work for MG-20 and with all different values?

I searched in Newark, Mouser and Digikey but couldn't locate the resistor for MG-20.

Also do I need to specify wattage or any other specifications and what maximum value i can use without harming the speakers?

I send email to Magnepan but couldn't get much help.

Quote:

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Originally Posted by K-High-Fi

Please can anyone show me the link for non-inductive resistors ( in series) which can work for MG-20 and with all different values?

I searched in Newark, Mouser and Digikey but couldn't locate the resistor for MG-20.

Also do I need to specify wattage or any other specifications and what maximum value i can use without harming the speakers?

I send email to Magnepan but couldn't get much help.

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Here's another source -- a favorite of audiophiles: Parts Connexion, (HERE).

You'll want Mills 12 watt non-inductive resistors; order pairs of different values and see which value works best. All are listed HERE: 1 ohm (see 1R0 / MRA-12), 1.2 ohm (1R2 / MRA-12), 1.5 ohm (1R5 / MRA-12).

Magnepan doesn't have the best responses where email is concerned. You'll get the best results by calling them on the phone. They are very friendly and quite helpful over the phone.

Thanks Feanor very much for the link, very helpful.

The resistor comes with MG-20 have: 10 watt and I think 5 % tolerance, is it ok if I use 12 watt with 1% tolerance?

Here is the information written in Magnepan resistor:
CP-10 Mexico 10 W
1 ohm 5% Dale 9636

Also, can I use below 1 ohm and above 2 ohms?

I would be careful about changing the wattage. It's possible that a resistor with too high a wattage could allow tweeter damage although going from 10 to 12 watts isn't a very large change. Replacing resistors is much cheaper than ribbon replacement. Using 1% resistors instead of 5% will give closer matching of their value. That's always a good thing.

Magnepan would probably approve closer tolerance resistors but not ones with a higher wattage rating.

Changing the value will change the tweeter level. A higher value, less treble and vice versa.

So is there any risk to the tweeter if i use 12 wattage ?

As for value, can I go up like to 3 ohms or more without any risk ?

Quote:

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Originally Posted by K-High-Fi

So is there any risk to the tweeter if i use 12 wattage ?

As for value, can I go up like to 3 ohms or more without any risk ?

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I doubt that there is much additional risk from 12 watts vs. 10 watts -- a resistor will not protect your tweeter like a fuse in any case. If the problem was that you were sending too much power, the resistor would probably pass more than its rated maximum watts for long enough before failing to damage you tweeter.

You could go to 3 ohms resistance or virtually any value without harming your speaker.

May i ask if i want to put sound absorbing panels at the first reflection points on the side walls, what the most suitable materials or brand for MG-20 ?

Can I use curtains or normal fabric?