I have a pair of simple 2 Way American Studiocraft 110 Studio Monitors circa 1970's.
I have them hooked up to my Desktop via a Rotel RX-850 Amp.
They're a lot of fun and very competent near field speakers.
I popped the drivers this afternoon to look inside.
6" Woofer & 1" Tweeter both wired directly in parallel to the Binding posts.
There is no traditional crossover as such.
The internal electronic component is a yellow part.
It has the following printing on it: " 2.2 +- 10% 250VMP ".
It's wired directly between the -ve Binding Post and the -ve Terminal of the Tweeter.
Is this a 2.2 μF Capacitor or is it a Resistor?
Thanks
Cliff
I have them hooked up to my Desktop via a Rotel RX-850 Amp.
They're a lot of fun and very competent near field speakers.
I popped the drivers this afternoon to look inside.
6" Woofer & 1" Tweeter both wired directly in parallel to the Binding posts.
There is no traditional crossover as such.
The internal electronic component is a yellow part.
It has the following printing on it: " 2.2 +- 10% 250VMP ".
It's wired directly between the -ve Binding Post and the -ve Terminal of the Tweeter.
Is this a 2.2 μF Capacitor or is it a Resistor?
Thanks
Cliff
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Looks like a metallised polypropylene capacitor,
MPA/MPT cbb20 Axial Shape Metallized Polypropylene Film Capacitor-GLCAP
so it doesnt need replacing.
but seeing as the speaker is a bose studiocraft, you might consider swapping the tweeters and woofers and putting proper crossovers in them 🙂
cheers, Arthur.
MPA/MPT cbb20 Axial Shape Metallized Polypropylene Film Capacitor-GLCAP
so it doesnt need replacing.
but seeing as the speaker is a bose studiocraft, you might consider swapping the tweeters and woofers and putting proper crossovers in them 🙂
cheers, Arthur.
It's just fine. Cool looking vintage speakers. Bose is not crap as indicated, they have just been overpriced.
If they sound good to you/ then leave them as is, very simple to try a new cap and hear if it’s better, you can spend as little as a dollar or has high as 500. I would not change it as it looks like someone as all ready done that
It’s a simple 1st order type of high pass crossover for the tweeters and full range to the woofers, you could play around with using a low pass and high pass filters , that way you can block some of the highs out of the woofer,
You said they sound good as a near field speaker? So if you start playing around with the crossovers, you will lose out on what they are doing do. Good luck and have fun with them, you will only be out of your time and a few dollars
It’s a simple 1st order type of high pass crossover for the tweeters and full range to the woofers, you could play around with using a low pass and high pass filters , that way you can block some of the highs out of the woofer,
You said they sound good as a near field speaker? So if you start playing around with the crossovers, you will lose out on what they are doing do. Good luck and have fun with them, you will only be out of your time and a few dollars
When you say too old, are you referring to them having deteriorated over time, or fallen behind technologically speaking?
Hey A L.
I'm a Loudspeaker lover.
It doesn't matter what age or brand, I like playing around with them.
I have about a dozen pairs to enjoy and compare.
I particularly enjoy acquiring vintage although I'm open to any era.
I'm beginning to become more convinced that well designed DIY Loudspeakers are the best option these days if you want new.
Saving on the labour, you can concentrate on ensuring all the parts (crossovers included) are with minimised compromise.
Tests performed by GR Research on latest offerings by companies such as Klipsch reveal some of the compromises Loudspeaker companies are resorting to to get the price down in a competitive market.
These days, many wives (sexist 😉) nag their partners to trade in their vintage Loudspeakers because they no longer fit the decor.
Some of these Loudspeakers might be in need of some attention (deteriorated foam surrounds, poor or deteriorated electrolytic capacitors, maybe iron connectors, improper set up, or mismatched AMP) and may not have been sounding their best.
These Studiocraft SC 110's might be old but they're very pleasing to listen to.
I hooked up a pair of Dali's tonight for a comparison.
After playing 3 tracks, I then hooked up the Studiocraft's to compare.
Deeper, pleasing bass, greater depth, more detail, and smoother than the Dali's.
Very listenable.
I'm buying Capacitors of the same value for other projects.
I might slip one into the Studiocrafts to listen for any improvement, otherwise I think I'll leave them as they are.
So many respected brands have sold their souls to the $.
Many pump out offerings built to a price rather than a standard.
Just curious why old speakers aren't worth improving?
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It will likely last forever and polypropylene is the best, but I'd be tempted to neaten the sloppy soldering and add some heatshrink.
Good advice Mark.
I'm ordering quality solder and have heat shrink on hand so I'll touch up the joints.
It'll be an opportunity to wire in a 2.2 μF Capacitor from another project to listen for any significant improvement.
I might even mould some mastic between the driver magnets and frames for rigidity.
In this instance we are talking about investing AUS$12.
If you don't know the specifics or the condition of my actual speakers how can you say they are not worth improving?
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I did not say that they are not worth improving. I said that I would not spend anything for those speakers because they are too old.
Do you think spending AUS$12 will make any difference in your speakers sound ? I am curious now, what did you buy?
Do you think spending AUS$12 will make any difference in your speakers sound ? I am curious now, what did you buy?
I have no idea.
This whole process is an exploration to learn what does and what doesn't work.
Given others experiences, many vintage speakers were built with electrolytic capacitors in their crossovers
Due to their nature electrolytic capacitors are known to deteriorate.
In many cases this can be over as little as 10 to 15 years.
If this is the case, then, many original crossovers may not be functioning to their designers specifications.
This may affect the speakers performance to varying degrees
Capacitors are available at different price points.
Your choice will depend on the value and quality of your entire system.
The quality of the Amplifier is just as important as the speakers.
So in my case, buying $100 capacitors would be overkill and I wouldn't realize much of a difference over an $8 capacitor.
But as long as it's of a reasonable quality, for such a small investment, the benefit would be to restore the electronics back to the designers specifications.
One could go a step further by analysing the speakers via a microphone and software, measure the deficiencies and redesign a quality crossover to overcome any measured issues.
A few months ago I recapped my sisters 1970's JBL Studio Monitors.
Previously they sounded dull and lifeless, but after a $30 upgrade to the crossovers, they now sound cleaner, with greater dynamic range.
My sister was very pleased with the difference in sound.
There are many inexpensive tweaks which can be done to speakers to get them to an acceptable sound quality.
I'm experimenting with cabinet bracing, insulation, speaker driver treatment, crossover upgrades, and removal of sources of degradation such as wire terminals.
You'll be surprised at some of the poor quality parts that go into modern Loudspeakers, mainly so manufacturers can market their products at given price points.
These days you'll find operators who make a living out of analysing brand new Loudspeakers and designing DIY upgrades to overcome deficiencies.
You might ask yourself, why didn't the manufacturer build the speakers correctly in the first place.
The answer is price.
With Loudspeakers there's between 500% and 1,000% mark up.
That is a pair of $1,000 speakers need to be between $100 and $150 to build.
I've heard the example of the Klipsch RP -600M.
People are raving about them.
It has been said that the crossover which goes into them would have cost no more than about $12.
The minimum for a reasonable polypropylene capacitor alone would have to be around $10 - $15.00
That's before you're even talking about the inductors, resisters, terminals and wiring.
There are all manner of vintage speakers around.
Some will always be junk, others might have potential given some alteration.
So, I'm thinking, it doesn't matter whether a product is new or vintage.
It's all down to the build quality.
Many vintage speakers were built very well and some sport expensive drivers.
Given many are being thrown out, traded in, or discarded, some can be good performers, given some attention.
I don't think it's their age, but rather their build and condition.
The other thing is that Loudspeakers are as much an art as they are a science.
Their nature is of compromise.
It's very difficult to design Loudspeakers to perform well at all levels.
Hence you get speakers offering different sounds.
For example, I understand there's what's referred to as English Sound.
Hi in detail at mid and upper range but lacking in deep bass.
Then there's the West Coast sound for rock and roll.
Just references to deficiencies in different offerings.
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Be that as it may Cliff, we should return to the fact that you simply asked for a particular part to be identified.
It is a high quality, high voltage polypropylene capacitor and you will find little, if any, sonic difference in replacing it.
Concentrate on the other improvements that you outline, as they may prove of greater benefit in this case.
It is a high quality, high voltage polypropylene capacitor and you will find little, if any, sonic difference in replacing it.
Concentrate on the other improvements that you outline, as they may prove of greater benefit in this case.
Thanks G.
Agreed.
As you say, someone has already upgraded the caps in the Studiocrafts.
As I'll be ordering 2.2 μF Capacitors for another project, I'll try these in the Studiocrafts, just to ensure the yellow caps are up to par.
While at it I'll just tweak the drivers with mastic, clean up the solder points and make sure the boxes are lined properly.
Thanks for your input.
C
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