6.0mf changed to 5.6mf will it make a differance

[proview]

hi
I can't get a 6.0mf cap for the crossover on the Lineup R44. I have got a 5.6mf cap will it make much of a differance and what will be the differance can I get round it (without getting a 6.0 cap) any help would be good as its first build!
cheers

[Face]

Where are you located that you can't source a 6.0uf cap?

[---k---]

Yes, it will make a difference. Will it be audible? Probably depends on your ears, your room, your setup, tolerance of the parts, etc.

You can use 2 - 3uf twisted together in parallel to get 6uf. I would recommend that first, just because. If you can't do that, I wouldn't sweat the 5.6 too much.

[ThomasW]

Really depends on the tolerance of the 5.6mfd cap. If it's say a 10% tolerance and happens to be on the low side, you could be actually using a something close to 5mfd and that's probably a bit too low. If it's on the high side of the tolerance you should be fine.

This of course means you need to measure the value of the cap to know whether or not it will work.

[JonMarsh]

+1

Another possibility is parallel a 1 and a 5. Thing is, cap manufacturers are generally real good at what they do, to control costs, and they'll almost always be on the low side of nominal cap value, with a small guard band to be sure they aren't out of tolerance. I normally rcommend buying 5% tolerance or better.

[Jed]

I'd get a 6.2uf cap if you don't want to buy caps to parallel values and make 6.0uf. Also, the 6.0uf value in the R44 is part of impedance correction, so going from 6.0 to 6.2 hardly impacts the FR at all.

Jed

[evilskillit]

Thing is, cap manufacturers are generally real good at what they do, to control costs, and they'll almost always be on the low side of nominal cap value, with a small guard band to be sure they aren't out of tolerance. I normally rcommend buying 5% tolerance or better.

Interesting point. When I got my LCR meter I measured every component I could find. I found almost all my inductors to be higher than marked by a nominal amount. From .3 to 0.05. Except for the steel core inductors I bought, they were all almost 0.2 lower than marked.

With caps they were all within 0.05 of the marked value. Except for two erse 16.9 caps which were actually 17.2 or 17.3. Probably close enough, but I threw em in the parts bin and bought some solens instead.

So far in the limited time since I got my meter Erse components are decently close but PE components are damn near always right on, even their 5% caps.

[JonMarsh]

For example, in the past I've measured LARGE numbers of GE 10 uF PPMF caps that were a buyout from Madisound; almost all came in between 9.85 and about 9.9 uF. That's measuring at 10 kHz test frequency, on an LCR test setup that is NIST calibrated and with an accuracy of 0.1%.

[proview]

Hi all
thanks for the input, I decided to fit them, as I had to get all the stuff for the build from europeaudio and it was a bit long winded. They are Audin 400v 5% caps as some of you have said tolerances may help / hinder the swap. As I have not any speakers to reference these against I probably will not know the difference.
BTW what will fitting the 5.6mf do to the sound will it be louder / softer, bass deeper / less deep base?
As you can tell first attempt at speaker building and I know nothing, tried to get them finished today but have got to pack for hols tomorrow

Jed have just reread your input re impedance correction I hope I will not blow anything up?

cheers

[Jed]

Jed have just reread your input re impedance correction I hope I will not blow anything up?

cheers

You'll be fine with a 5.6 or 6.2 or 6.0 for that cap in the R44.

[Not2Evil]

I would like to caution the OP about mixing the mili (m) with the micro (u) prefix.

All of the xovers I've seen use micro farads (uF), but I bring it up because some huge, low voltage caps ARE available for bypassing and hold up circuits for car audio (mF and even F).

That would stink if you accidently bought a value 1000 times larger than expected.

[---k---]

I always get the prefix wrong in my posts...

[proview]

Hi
Well I finally got them finished, after being stuck in Morocco due to the Volcano, oh the hardship of staying round the pool and only 29c! any how, they are fantastic, I love them sound really sweet and detailed, even my wife likes them but says "don’t get the bug to build more"!!
one final question what would the efficiency of the r44 be just so I know for reference ( if I ever do another)

cheers for all the help
Proview
:B

[Amphiprion]

Where are you located that you can't source a 6.0uf cap?

The real world, where the E24 series dominates the capacitor landscape 5.6 or 6.2 is as close as most 5% tolerance caps will get, but I guess hobbyist-oriented audio cap companies do make odd values like 6.0. Never see that in professional electronics though.

[Jed]

6.0 uf

[fordmaker]

Interesting to note that the Madisound descriptions clearly use "mfd" and "MFD" to both say Micro Farad. What would the abreviation for Millifarad be?

[Amphiprion]

Millifarad abbreviation is mF. It's rarely used, as people stick with uF for electrolytics or jump straight to Farad for things like electric double layer caps. If I ever see an mF I look at the schematic and I can tell for sure what is meant, and it's almost always uF. As far as capacitors themselves, unless it's a big electrolytic or an electric double layer cap, mF should almost always be interpreted as uF (or µF, for those who know alt codes).

[Amphiprion]

Also, for those not familiar with the E series, here is a good link:

http://www-k.ext.ti.com/SRVS/Data/ti/KnowledgeBases/analog/document/faqs/res_e.htm

Each E series corresponds to a % tolerance for that series, and the values within a decade are based on that. Once that's understood, it's easy to see why 6.0 would be considered an 'oddball' in professional electronics. IIRC, LSPCad even had a setting in its optimizer back in v5 that would force it to use E12 or E24 parts only when optimizing. These E series are applicable to resistors, capacitors, and inductors alike, with resistors predominantly being the ones that are available in anything tighter than 5% tolerance.

[proview]

one final question what would the efficiency of the r44 be in db please
proview

[Jed]

one final question what would the efficiency of the r44 be in db please
proview

Around 88.5db/2.83v/m sensitivity

[Speedskater]

Probably for one hundred years "mfd" or "MFD" meant micro farad at the hobbyist or technician level, only recently when very large capacitors became available did the correct Milli-farad become important. Many, many older publications have the older incorrect usage.

[Not2Evil]

I remember when crystal values where embossed on the case as kilocycles, and when resistors had color codes. I wonder if they even teach the color code any more, and if they somehow made it politically correct.

Time marches on.

[Amphiprion]

They do still teach resistor color codes in electrical engineering curriculum, and they have tried to make it politically correct, but I never remembered any of the lame ones they came up with. The only one I ever remembered was the politically incorrect one my first boss told me, and that one stuck. I graduated in 2003. Everything I do now is SMT though, so even though I am theoretically capable of reading a color code I find measuring it with a meter to be much faster and more reliable than, uh, me Thank God for Smart Tweezers (R) when I do 0603 and 0402 stuff. They can't even print the digits on them.

When did cycles become Hertz? I've seen a lot of older books that use cycles so it must have been since WWII?

[Amphiprion]

And Wikipedia with the answer:

The hertz is named after the German physicist Heinrich Hertz, who made important scientific contributions to electromagnetism. The name was established by the International Electrotechnical Commission (IEC) in 1930.[5] It was adopted by the General Conference on Weights and Measures (CGPM) (Conférence générale des poids et mesures) in 1960, replacing the previous name for the unit, cycles per second (cps), along with its related multiples, primarily kilocycles per second (kc/s) and megacycles per second (Mc/s), and occasionally kilomegacycles per second (kMc/s). The term cycles per second was largely replaced by hertz by the 1970s.

[---k---]

I'm going to have to google resistor color codes to see what the heck you guys are talking about.

[ThomasW]

I'm going to have to google resistor color codes to see what the heck you guys are talking about.

[---k---]

Thanks Thomas.
I haven't seen that. I'll have to print it out and keep it somewhere. Last week I just went to Madisounds website and scrolled through the pictures until I found on that matched.

Now... how about the politically incorrect method of remembering??? I was looking for a good laugh.

[Amphiprion]

"Bad Booze Rots Our Young Guts But Vodka Goes Well" is one of the better more politically correct ones. There are lots of significantly poorer variations.

The very non-PC one is as follows (hiding it with spoiler tags just because I feel bad posting this on the internet, but it's what people actually remember)

Removed

It even works in the tolerance bands with the GSN (gold, silver, none)

[---k---]

WOW! That is much much worse than I imagined. I can see why you hide it. You can delete it. I would hate for that to show up in a search on google.

[Face]

FYI, when you wrap text in [ PHP ][ /PHP ] tags(remove spaces), it shouldn't be indexed.

For example 

[Amphiprion]

For what it's worth, I had a supervisor who had been a radio operator in the Navy. He went through basic probably in the early-mid 90's. The full-on non-PC one was what he was taught in the military. The justification of race being used was that it helped to distinguish the two B colors/words that start the sentence.

As for it showing up in a search, meh. Everyone in my field has heard it. An HR person might flinch at it, but no one who actually works in my area would care that I posted it so long as I put the disclaimers. All the same, I have removed it now that the interested parties have read it.

[Amphiprion]

Actually, Wikipedia has quite the list ways to remember them. This is direct from Wikipedia, please feel free to edit this moderators if anything is too offensive.

Mnemonics

A useful mnemonic matches the first letter of the color code, by order of increasing magnitude. There are many variations:

* Bad boys rape our young girls behind victory garden walls.[6][7]
* Bad boys run our young girls behind victory garden walls.[8]
* Bad boys rape our young girls but Violet gives willingly.[6][7]
* Big boys race our young girls but Violet generally wins.[9]

The tolerance codes, gold, silver, and none, are not usually included in the mnemonics; one extension that includes them is:

* Bad beer rots our young guts but vodka goes well – get some now.[10]

Since B can stand for both "black" and "brown", variations are formed such as "Black boys rape our young girls...".[8]

Humorous, offensive, or sexual mnemonics are more memorable (see mnemonic), but these variations are often considered inappropriate for classrooms, and have been implicated as a sign of sexism in science and engineering classes.[11] Dr. Latanya Sweeney, associate professor of computer science at Carnegie Mellon, a black woman, mentions the mnemonic ("black boys rape only young girls but Violet gives willingly") as one of the reasons she felt alienated and eventually dropped out of MIT in the 1980s to form her own software company.[12][13]

A politically-correct mnemonic that has attained some traction in recent years is:

* Big brown rabbits often yield great big vocal groans when gingerly slapped.[14][15][16]

Another mnemonic that is not offensive and can be used in the classroom is:

* B. B. ROY of Great Britain has Very Good Wife.[17][18][19]

Other mnemonics commonly taught in UK engineering courses include:

* Bye Bye Rosie Off You Go Birmingham Via Great Western[20]
* Bye Bye Rosie Off You Go Bristol Via Great Western[21]
* Bye Bye Rosie Off You Go do Become a Very Good Wife[19]

* Bill Brown Realized Only Yesterday Good Boys Value Good Work[21][22]

The colors are sorted in the order of the visible light spectrum: red (2), orange (3), yellow (4), green (5), blue (6), violet (7). Black (0) has no energy, brown (1) has a little more, white (9) has everything and grey (8) is like white, but less intense.[23]

from:

http://en.wikipedia.org/wiki/Electronic_color_code

[---k---]

I think the fact that it is so shocking really reinforces it in our brains. I made no attempt to memorize it, but there it is stuck in my brain. I'm not sure I would remember the beer, rabbit, etc. ones.

[Not2Evil]

If you find that shocking, you wouldn't believe the nickname of heat sink grease or the name of a short, stubby antenna.

A hundred + years of male dominated electronics hasn't had much of a need for diversity. But, probably not much different than other professions. Plumbing has lots of inuendos also.

There are a lot of things that aren't polically correct, but most of them weren't intended to insult or harm others. Change the name of the Atlanta Braves and let it stop there. (Cause baseball sucks anyway)

What I need is more people telling me what I'm doing wrong, so I can do what I think is right even better.

Ok, let's build more and have fewer speakers, specially in the House. Triple inudendo, extra points for that one!

I love the Red Green show, can you tell? Getting old and crotchity is actually kind of fun.