MJAO G 098 - The Anagram - Crossover revision

scorpion · « **Reply #20 on:** 8 Mar 2009, 10:20 pm »

jkelly,

They are hidden away among Car audio loudspeaker units: http://www.bmm-electronics.com/Product.asp?Product_ID=7637 . They sell in pairs so the price is for two units.

Richard,

I am bringing up my B200s from the basement for a more thorough comparison. I'll come back with an answer to the best of my ability.

The 'Volks-OB's with Monacor SP-130 X/8 are more easy to judge about in direct comparison. They sound a bit 'harder' and when pressed the SP-130 X/8s also are a bit cracking/blaring. But that is at real high volume. The build quality of SP-130 X/8 is considerably below the MS-100CHQ. This is also reflected in the price.

/Erling

Telstar · « **Reply #21 on:** 9 Mar 2009, 11:27 am »

Erling,

I like minimalistic approaches and your new OBs are amazing on this regard.
Are you running all passive right?
If so, could you measure the overall impedance of the loudspeakers that put to the amplifier?

Could you PM a bill of materials costs?

Now, two technical questions:
1) Mirror placement of midrange and tweeter: did you try centered placement? Plus/Cons of both approaches.
2) Sloped baffle top. I think I guess the reason of this. But how would it sound with a straight (shorter) baffle top?

Thanks in advance. Your post made my morning

Telstar · « **Reply #22 on:** 9 Mar 2009, 12:09 pm »

PS: Got an European dealer for Alphas?

skite30 · « **Reply #23 on:** 9 Mar 2009, 07:26 pm »

I was looking at the monacor mid-range and couldn't help but notice it looks a lot like the fe-103's. Just thought people who have built MJK's 2-way OB could possible give the 3-way passive a try by just ordering a pair of tweeters an inductor and a couple of cap's. What do you think? Anyone capable of running on simulation on it?

-Richard- · « **Reply #24 on:** 10 Mar 2009, 12:49 am »

Hi Erling ~

Thanks in advance for taking the time and effort to bring your B200's up from the basement for a careful comparative listening with your new 3-way Open Baffle "triumph".

I am excited to read what your thinking is about the differences and/or similarities between each Open Baffle speaker.

With Warmest Regards ~ Richard

BrassEar · « **Reply #25 on:** 10 Mar 2009, 05:51 pm »

In my experiments with the Alphas I have always thought that setting the level of this driver relative to the others in the speaker was more important than the xover point, slope, etc.

Simply an amazing driver for the price up to 2 kHz or so.

mor2bz · « **Reply #26 on:** 11 Mar 2009, 12:07 am »

any impedance measurements? must one use a chip,class d, or SS amp or could a tube
amp be used? thanks for sharing your design.

scorpion · « **Reply #27 on:** 11 Mar 2009, 12:17 pm »

Richard, I have been through quite an interesting and timeconsuming comparison and investigation of Eminence Alphas + B200 with the MJAO.
I think I have some results that might interest B200 owners in general, so I'll summarize my findings in a new thread: 'Eminenca Alpha15 + B200 vs MJAO G 098'.

skite30, I think Fostex FE 103 E and Monacor MS-100CHQ are two completely different speakers. I wouldn't give any recommendations for MJK's Eminence Alpha15 - Fostex FE 103 E OB based on the looks of MS-100CHQ.

Telstar and mor2bz, Impedance to begin with. I have made measurement manually with this result: (selected frequencies) 40 Hz - 10.4 ohms, 80 - 5.3,
160 - 5.8, 320 - 5.8, 630 - 4.1, 1200 - 4.1, 2500 - 4.6, 5000 - 6.9, 10000 - 10.1 and 20000 Hz - 25.2 ohms. Minimum is 4.1 ohms in the 600 - 1200 range.
Any good amplifier should be able to cope with the load. I would label it a 4 ohm speaker.

Bill of material for one speaker (no VAT included and no transport):

Speakers from BMM Electronics (http://www.bmm-electronics.com/intro.asp)

1 MS100CHQ   56.75 US%body%nbsp; (But sell in pairs)
1 DT-28N 27.20 US$

From Premia Audio UK (http://www.premiaaudio.co.uk/epages/194597.sf/sec__U_ylihXS_/?ObjectPath=/Shops/194597/Products/EM1231). They seem to be
an interesting supplier for Europe. In US there would be several alternatives.

2 Eminence Alpha15 84 US$

Crossover:

From BMM Electronics (http://www.bmm-electronics.com/Product.asp?Product_ID=5450) ferritcore coil (In Europe, in US I would go for ERSE Supe Q 2.0 mH inductor at PE)

1 HQ56/1.8/160   19.4 US$

From DIY HiFi Supply Capacitors (http://www.diyhifisupply.com/?q=catalog/35/obbligatofilmoilcaps). They have very favourable transport cost for electronic components.

1   Obbligato 70 uF Film Oil Cap   29 US$
1   Obbligato 10 uF Film Oil Cap   11 US$ (To form the 80 uf capacitor in the crossover)
1   Obbligato 4.7uF Film Oil Cap   6.75 US$

I have some Dayton capacitors coming in, I can say something about them later. The Obbligatos are exellent sounding and more than worth the price.

The sloped baffle is more of a visual effect but an attempt to minimize baffle and diffraction effects. I don't think a square baffle and centered placement would bring any real audible difference.

And Telstar this is an all passive design as shown.

/Erling

Telstar · « **Reply #28 on:** 11 Mar 2009, 12:29 pm »

Quote from: scorpion on 11 Mar 2009, 12:17 pm

Telstar and mor2bz, Impedance to begin with. I have made measurement manually with this result: (selected frequencies) 40 Hz - 10.4 ohms, 80 - 5.3,
160 - 5.8, 320 - 5.8, 630 - 4.1, 1200 - 4.1, 2500 - 4.6, 5000 - 6.9, 10000 - 10.1 and 20000 Hz - 25.2 ohms. Minimum is 4.1 ohms in the 600 - 1200 range.
Any good amplifier should be able to cope with the load. I would label it a 4 ohm speaker.

I think that's too hard for my F3, even if the crossover is very light. Same should apply for 5-15W SET tubes.

-Richard- · « **Reply #29 on:** 11 Mar 2009, 05:49 pm »

Hi Erling ~

I look forward with great interest to your new thread 'Eminenca Alpha15 + B200 vs MJAO G 098'.

Thanks for all of your hard work and sensitive, careful listening!!! It is very important work and it is very generous of you to share your insights with us!!

With Warmest Regards ~ Richard

Telstar · « **Reply #30 on:** 12 Mar 2009, 12:08 pm »

Quote from: Telstar on 11 Mar 2009, 12:29 pm

I think that's too hard for my F3, even if the crossover is very light. Same should apply for 5-15W SET tubes.

I got an idea: what if I use two midrange drivers? That should improve the impedance.

PS: which is the sensitivity?

panomaniac · « **Reply #31 on:** 12 Mar 2009, 04:17 pm »

If you use the same midrange it is 4 ohm. So you would put them in series. Is that what you want to do? Bring it up to 8 ohms?

Telstar · « **Reply #32 on:** 12 Mar 2009, 05:51 pm »

Quote from: panomaniac on 12 Mar 2009, 04:17 pm

So you would put them in series. Is that what you want to do? Bring it up to 8 ohms?

Yes. Would it work?

scorpion · « **Reply #33 on:** 12 Mar 2009, 08:20 pm »

Telstar, also the Alphas will border to 4 ohm in parallel.

But Monacor has three similar midrange drivers, beside the MS-100CHQ also MSH-116/4 and MSH-115.
'For your information the MSH-116/4 use the same Cone and voicecoil System but have a cheaper basket. The MSH-115 is very similar with a 8 Ohm voicecoil' is a direct quote from a mail conversation I had with Frank Kuhl of Monacor.

I simulated the MSH-115, http://www.bmm-electronics.com/Product.asp?Product_ID=5579 , and together with one Alpha15 on my baffle with the same good result as for MS-100CHQ just a few decibel less sensitivity around 90 dB/1 watt. For an 8 ohm system why not try MSH-115. This will also be cheaper with only one Alpha but you will have to work a bit on the crossover.

/Erling

Telstar · « **Reply #34 on:** 12 Mar 2009, 09:15 pm »

Quote from: scorpion on 12 Mar 2009, 08:20 pm

Telstar, also the Alphas will border to 4 ohm in parallel.

But Monacor has three similar midrange drivers, beside the MS-100CHQ also MSH-116/4 and MSH-115.
'For your information the MSH-116/4 use the same Cone and voicecoil System but have a cheaper basket. The MSH-115 is very similar with a 8 Ohm voicecoil' is a direct quote from a mail conversation I had with Frank Kuhl of Monacor.

I simulated the MSH-115, http://www.bmm-electronics.com/Product.asp?Product_ID=5579 , and together with one Alpha15 on my baffle with the same good result as for MS-100CHQ just a few decibel less sensitivity around 90 dB/1 watt. For an 8 ohm system why not try MSH-115. This will also be cheaper with only one Alpha but you will have to work a bit on the crossover.

/Erling

Hi Erling,

For the woofers I can go active, but for midrange and tweeter, I want high sensitivity (ideally 100dB) and high impedance (6+ ohm) to let my F3 shine.

The best thing of these Monacor drivers is price

Did you think of using two midranges? I was thinking of a MTM layout, the MSH-115 is indeed interesting (and even cheaper).
What do you think? How would you design the crossover in this case?

Thanks!

scorpion · « **Reply #35 on:** 12 Mar 2009, 09:43 pm »

Telstar,

MTM and MS-100CHQ serially connected also simulates promising. I would just try a 40 uF capacitor instead of the 80 uF to begin with. KISS !
Sensitivity should be about the same as for the MJAO. Just adjust placement a bit. Price was one factor which I found interesting but the best thing with these Monacors really is price/performance.

/Erling

jeffac · « **Reply #36 on:** 13 Mar 2009, 02:20 am »

Hi Erling,

Just a few words to say that your continuing efforts in designing a great sounding yet simple OB speaker are fantastic, and will have folk scrambling to copy I'm sure. Well done.

As with Richard's design and some of MJK, it's the simplicity of an all passive and possible single amp solution that seems always to generate excitement. In this regard, your choice of 3 way, cheapish but 'good for OB' drivers well matched in SPL and a simple crossover design is ever so reminiscent of the KISS approach touted by Lukasz Fikus (aka Lampizator) for quite a while now, albeit with his passion for vintage AlNiCo rather than newer drivers.

http://www.lampizator.eu/SPEAKERS/PROJECTS/P17/Endorphine%20from%20Kingston%20Kitchen.html

With such simple and cheap-to-build designs like these, boxed speakers will have to become a thing of the past in a few years.

OK, that said, back to work in fine tuning mine.

cheers.. jeffac

Telstar · « **Reply #37 on:** 13 Mar 2009, 04:51 pm »

Quote from: scorpion on 11 Mar 2009, 12:17 pm

And Telstar this is an all passive design as shown.

/Erling

I'm thinking how would it look with 2x alphas (or 2x peerless, see this thread ) active, and with U baffles to go as low as 30hz.

And MTM with SH-115 midranges to keep 8ohm impedance. My goal is 96dB.

Attainable?

scorpion · « **Reply #38 on:** 13 Mar 2009, 07:52 pm »

Telstar,

Referring to mail.

jeffac,

Thank you very much ! It's appreciated.

/Erling

nicoch46 · « **Reply #39 on:** 15 Mar 2009, 12:27 am »

why not dipole tweeter ? like bg neo3 , 36$