Recapping Monitor 11

Shacky

I assume the 0.5 cap is in line with Tweeter. What about the 4.9 uF cap :question:

This doesn't show the crossover detail to see how critical that 4.9 is.

Also - are the 45 uF caps used separately or combined in the circuit?

Shacky

No feedback to go by. Here's what I ordered:

CLARITY-74830 Each 0.47uf 250VDC, +/- 3%, ESA
Series, Capacitor
2 2 5.59 11.18
Discount 20.00% -1.12 -2.24
MATCHFEE 1 1 MP MATCHING FEE PER PAIR 1.00 1.00
AXON-73687 Each 47uF 250V 5% TRUE
CAPACITOR
2 2 8.93 17.86
MATCHFEE 1 1 MP MATCHING FEE PER PAIR 1.00 1.00
AXON-73688 Each 43uF 250V 5% TRUE
CAPACITOR
2 2 8.21 16.42
MATCHFEE 1 1 MP MATCHING FEE PER PAIR 1.00 1.00
AXON-73713 Each 4.7uF 250V 5% TRUE
CAPACITOR
2 2 1.69 3.38
MATCHFEE 1 1 MP MATCHING FEE PER PAIR 1.00 1.00
MILLS-71909 Each MRA-12 4R7 1% MILLS
RESISTOR
4 4 4.95 19.80

F1nut

The 4.9uF for the tweeter, the 0.5uF is not.

Shacky

uh-oh

Shacky

Too late to change order with PC. So would it be that bad to use the Axon caps 4.9 with tweeter? I think I have some Solen 4.7 left over from previous project too.

Or I could start another bypass thread and suggest I bypass either the Solen or Axon with a nice Russian 0.1 or two :cheesygrin:

heiney9

Axon and Solen aren't the greatest sounding caps for a tweeter circuit, certainly better than the aged stock eletrolytics. Try the Axon first and if it's objectionable then maybe try a bypass cap. I am not in favor of using bypass caps, but you'll have to decide for yourself.

H9

Shacky

I was looking at Sonicaps on Sonicraft site. On Gen I Sonicaps can I use 200 VDC or do I need 600 VDC version? Thought I remembered reading somewhere that anything greater that 160 is OK for speaker crossovers.

Shacky

OK I see 200 VDC Sonicaps used elsewhere so assume they are good.

So now another example of stupid is as stupid does - I ordered 2 x 43 uF Axons and 2 x 47 uF Axons. Thinking the each pair worked together and would equal combined 2 x 45 in schematic.

I'm thinking now that's not true and the reason for 2 x 45 uF is the midranges work separately. Since one Midrange focuses on 600 hz and below and the other the full midrange, how would you suggest I make best use of what I ordered? :redface:

TNHNDYMAN

^ start over

F1nut

TNHNDYMAN wrote: »

^ start over

Solid advice.

Shacky

I hear ya. I didn't think and confirm this one through before pulling the trigger. Too anxious to hear these at their best.

So how about some advice on better set of caps? I like the sound of Sonicaps in my Forte's. So maybe I go for Sonicaps on the 4.9 caps. I see Sonicap come in 4.7 and 5.0.

I'm not familiar with Clarity caps. If they are warm lke Sonicaps I could save another shipping charge.

Just for s#$$s and giggles - can anyone point out which position 45 uF cap is for the full mid and which is for the low mid driver?

Shacky

I would say looking at the attached that the outer 45 uF cap is for the low bass driver. Am I right?

TNHNDYMAN

I would suggest looking at your actual crossover and replacing as needed w/ values that are being used currently.

Shacky

For those in the know - please just tell me if you know which 45 uF caps for high and low woofer. The 43's and 47's I ordered are well within 10% of 45 and I'd prefer not to spend $20+ on shipping to replace. I'll hedge and put higher values in line with the low freq woofer.

F1nut

I can't tell from the schematic. You'll have to trace the blue and black leads to figure out which one is driver 1 and driver 2. That said, you are darn close to 5% tolerance and for that circuit I think that's close enough.

Shacky

Thanks F1!

Shacky

Now that I think of it the driver I changed out was in the high midrange position - had foam behind it - and had black wire. So Driver 1 would be high mid if that's the case. Goes to show I can't read schematics :rolleyes:

Shacky

So which cap is for Driver 1? C3 or C4? And how about C2? Which driver does it impact?

Shacky

Started taking one of the M11's apart tonight. The one that had blown tweeter fuse and blown midrange. Boy whoever blew these sure did a number on this one. One of the 4.5 ohm sand resistors burnt up pretty good. Left lots of char underneath and fried nearby zip tie holding coil in place. The burnt one read 5.1 ohms. The othe 4.6.

Shacky

Here are a couple of pictures of work in progress on first crossover. Have new Mills resistors, small Clarity Cap, and first 47 uF cap. Second picture show how I added second large cap. Since I ordered 43 uF's adding some 4.7 uF Solens I had in stock. Putting that combo on the low pass midrange.

Shacky

Finished one crossover. Have to reconnect wires to terminal. I think I'll replace those plast one ways with something stronger since crossover is now a lot heavier.

I know most here don't fancy bypassing caps but I decided to use a high quality PIO 0.1 to bring the Axon 4.7 a little closer to 4.9 target. I strapped and hot glued caps to keep them from rattling around.

Shacky

Finished one crossover. Have to reconnect wires to terminal. I think I'll replace those plast one ways with something stronger since crossover is now a lot heavier.

I know most here don't fancy bypassing caps but I decided to use a high quality PIO 0.1 to bring the Axon 4.7 a little closer to 4.9 target. I strapped and hot glued caps to keep them from rattling around.

headrott

Is the little green capacitor a Russian K75-10?

Shacky

K42

F1nut

Since I ordered 43 uF's adding some 4.7 uF Solens I had in stock.

You're doing what?

I decided to use a high quality PIO 0.1 to bring the Axon 4.7 a little closer to 4.9 target.

Read this....

Bypass capacitors. In addition to the Multicap RTX, I have tried either .1 ?F or .01 ?F bypasses from Sonicap (Gen I and the Teflon? Platinum cap), Hovland, AudioCap, and Wima. In every case the results were similar. Let me digress for a minute or so (depending on how fast you read) and talk about crossovers.

In the simple first order high-pass crossovers we are using for this capacitor comparison, the value of the single capacitor, together with the impedance of the loudspeaker driver, determines the crossover frequency. An 8 ?F capacitor with the 4 ohm impedance of the Magnepan quasi-ribbon tweeter gives a crossover frequency of about 5000 Hz (1/2πRC). A smaller value capacitor (for example, 4 ?F instead of 8 ?F) will raise the crossover frequency. If we used only the very small value .1 ?F capacitor without the 8 ?F, we would hear nothing because the crossover frequency is now almost 400,000 Hz. Even a dog would not hear it!

So why use a bypass at all? There are actually components of very high frequencies in some audio waveforms. Some are high order harmonics. If you think of a square wave, the right angles at the top of the wave are extremely high in frequency. Sometimes there are high frequency components in very fast audio sounds, for example, the instantaneous tap of a drum stick on a cymbal. These are the sounds that should be "helped" by including a small-value bypass capacitor in a high pass crossover.

Well, I don't think so. If the 8 ?F capacitor blocks frequencies below 5000 Hz and passes frequencies above 5000 Hz, why do we need what is actually another crossover for the same tweeter, but operating at frequencies already passed by the big cap? I am sure engineers have a very good reason, and a couple of them have tried to educate me on this subject. I respect the science and electrical theory on this subject, and my technical background helps me to understand it fairly well. But there is one small problem: the bypasses all sound bad! They add a quality that at first sounds like an increase in air and detail, but after a couple of hours becomes an intrusive harshness and discontinuity in the upper treble. Remove the bypass: all of the detail is present but without that grating and annoying sound. The high frequencies are cleaner, smoother, and much more enjoyable. It doesn't matter if the bypass cap is Teflon?, polystyrene, or common polypropylene, the results are very similar. And to be avoided.

Shacky

Another angle

Shacky

F1nut wrote: »

You're doing what?



Read this....

Yep I know I'm going to take some heat here for this. Bt I've had very good success with Russian PIO's as "bypass" caps in past and want to try it. If it is not successful I can easily cut it out.

I added the Solens 4.7 to the 43 Axon to make it closer to the 47's I orderd. When ordering these after brief look at layout I thought those two 45 caps were used together hence my orderin 2 x 47 and 2 x 43. But I now know I was wrong.

I put the 43 Axon + 4.7 Solens on the low pass woofer and the straight 47 on the high pass mid/woofer.

F1nut

The problem with that is the 4.7uF is going to act as a bypass cap. Honestly, you'd be better off starting over.

Shacky

Don't caps in parallel work together with combined compacitance?

F1nut

They do, but a smaller cap is faster than a larger cap, hence a bypass. If you have to use two or more caps to obtain a desired value it is best to have them as equal as possible.

Shacky

I'll listen to the one speaker and compare to original caps before moving forward.