I'm new to this forum and after observing for some time how eager the group is to lend their knowledge. I decided to seek feedback on ways to get the most performance out of my newly acquired Pioneer CS-77 loudspeakers. I realize they are not extremely well thought of but for someone like myself who is new to hifi I thought they would make a good starting point.
My goals are:
1) Stay within a $300 budget for the pair.
2) Achieve very good sound quality (not necessarily audiophile performance)
3) Change the usual suspects like capacitors/ coils if suggested.
4) Change drivers if that is the preferred direction of the group. note: all drivers are in good working order.
5)* Drastically improve bass which is really lacking above all other ills.
6) Listen and learn from the responses I receive
7) Have fun with the project.
Thanks in advance! Look forward to hearing the ideas that are to come.
My goals are:
1) Stay within a $300 budget for the pair.
2) Achieve very good sound quality (not necessarily audiophile performance)
3) Change the usual suspects like capacitors/ coils if suggested.
4) Change drivers if that is the preferred direction of the group. note: all drivers are in good working order.
5)* Drastically improve bass which is really lacking above all other ills.
6) Listen and learn from the responses I receive
7) Have fun with the project.
Thanks in advance! Look forward to hearing the ideas that are to come.
Like these?
If you are going to change drivers you should just start from scratch.
The XO parts don't look that bad, but it is a very simplistic design. You could consider a redesign.
Looks like a nice alnico woofer.
I'd consider making a new baffle so that the drivers could be mounted in a vertical array.
Stiffen the cabinet. Stiffen the mid enclosure.
Trim off the raised edges that hold the grill (and lose the grill).
Rewire.
Ductseal the baskets.
Treat the cones (that is one of the things i do for a living so i'd take it to extremes)
If bass is MIA, you need to figure out if the bass driver has drifted or the box needs redesign. You'll have to measure the T/S parameters. Hopefully you can retune for decent bass.
dave
If you are going to change drivers you should just start from scratch.
The XO parts don't look that bad, but it is a very simplistic design. You could consider a redesign.
Looks like a nice alnico woofer.
I'd consider making a new baffle so that the drivers could be mounted in a vertical array.
Stiffen the cabinet. Stiffen the mid enclosure.
Trim off the raised edges that hold the grill (and lose the grill).
Rewire.
Ductseal the baskets.
Treat the cones (that is one of the things i do for a living so i'd take it to extremes)
If bass is MIA, you need to figure out if the bass driver has drifted or the box needs redesign. You'll have to measure the T/S parameters. Hopefully you can retune for decent bass.
dave
Yep, those are the ones I have except those appear to have upgraded caps. Those are all excellent suggestions. If a person liked the grill could it be left in place and still achieve quality sound once finished? Also, what product do you use to treat the cones?
Thanks Planet10 for your speedy response!
Thanks Planet10 for your speedy response!
Yes, pointing on the edges ! What about redesigning it ?
Maybe just a -experimental- baffle
so it becomes an OB speaker system ( and tests should be made accordingly )
-The woofer is mounted as moderns do: onto the baffle from the front
-The midrange is freed from the plastic cilynder
-The tweeter is changed to a modern one
The first buyings are the tweeters and the coils ( about 4-5 mH or more
)
Then capacitors ( as it has been shown in those pics)...also 50 and 100 uF ( for the new 2nd order lowpass ) pairs
A resistor ( or net ) substitutes the L-pad or maybe it isn't needed
Maybe just a -experimental- baffle
so it becomes an OB speaker system ( and tests should be made accordingly )
-The woofer is mounted as moderns do: onto the baffle from the front
-The midrange is freed from the plastic cilynder
-The tweeter is changed to a modern one
The first buyings are the tweeters and the coils ( about 4-5 mH or more
) Then capacitors ( as it has been shown in those pics)...also 50 and 100 uF ( for the new 2nd order lowpass ) pairs
A resistor ( or net ) substitutes the L-pad or maybe it isn't needed
So far, it appears the biggest downside to this cab is the baffle. The good news is I'm not in a huge hurry to complete the project. I will gather information and plan out the project over the next several months. So the more replies the better. Then next winter commence the project. As a golf course superintendent in the mountain west, my job is very seasonal. Cabin fever sets in so it is nice to dive into another hobby through the winter.
Thanks again for the replies thus far!
Thanks again for the replies thus far!
Good news from tech development from the 70's
You can reuse those cabinets to house just a new 12" sub
and put the old speakers on a baffle above ( maybe with the same style, but the grill/tissue must be still avoided)
Tweeter changed ( also the 1st order filter on the midrange should/could be perfected to 2nd order ) or if you're satisfied by the sound of it ... I doubt becasue 16 kHz was the rule for cut off
You may invert mid and tweeter position, either, or put the woofer on the top
You can reuse those cabinets to house just a new 12" sub
and put the old speakers on a baffle above ( maybe with the same style, but the grill/tissue must be still avoided)
Tweeter changed ( also the 1st order filter on the midrange should/could be perfected to 2nd order ) or if you're satisfied by the sound of it ...
I doubt becasue 16 kHz was the rule for cut off You may invert mid and tweeter position, either, or put the woofer on the top
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My what great ideas have already been presented. I'm not a cabinet maker but it would seem somewhat easy to design a baffle that would mount flush with front edge of box. Of course then the grills would go bye bye. The baffle could be done in walnut veneer to match the rest of the cab much like Pioneer CS-77a models. From a driver selection standpoint, should i design the baffle to house a smaler woofer than the original 12"? Something like to 10" or maybe 8". I have started running simulations with various drivers on Winisd. Again much to learn. Very exciting stuff.
Thanks so much Guys!!! Your wealth of knowledge is appreciated.
Thanks so much Guys!!! Your wealth of knowledge is appreciated.
The most useful thing you can do is improve the crossover. It's frankly a trainwreck at present. The 12" woofer is running nearly fullrange to 2kHz and the whole thing has no resemblance to a three-way. Which is why the bass is all wrong.
SEAS Kit 503
Simple mods below make it look a whole heap better, but bear in mind I've assumed an 8 ohm bass. Some resemblance to the SEAS 503. But you should also measure the DC resistance of the drivers. They are quite likely 16 ohm units IMO. Hence a DCR around 12 ohms.
SEAS Kit 503
Simple mods below make it look a whole heap better, but bear in mind I've assumed an 8 ohm bass. Some resemblance to the SEAS 503. But you should also measure the DC resistance of the drivers. They are quite likely 16 ohm units IMO. Hence a DCR around 12 ohms.
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Thanks Steve,
Would the above schematic that you referenced make a good crossover design moving forward even if I decide to change to all new drivers? I do realize all values of capacitors and coils would need to be considered. I'm trying to get ideas as to what a well engineered 3 way crossover should look like. Also, in trying establish a little more clarity, is the 12 uf capacitor in my system the high pass for woofer at approx. 1,800 hz?
Best Regards
Would the above schematic that you referenced make a good crossover design moving forward even if I decide to change to all new drivers? I do realize all values of capacitors and coils would need to be considered. I'm trying to get ideas as to what a well engineered 3 way crossover should look like. Also, in trying establish a little more clarity, is the 12 uf capacitor in my system the high pass for woofer at approx. 1,800 hz?
Best Regards
help with driver selection
I have uploaded 3 potential drivers to use in the Pioneer CS-77 cabs. This is going on the plan to redesign baffle as been suggested in earlier posts. Are these good choices? I'm not looking for the absolute highest quality items just solid performers. I was able to run simulation with the Dayton 8" woofer in Winisd and it looks very good to me. Keep in mind I'm very new to this stuff, so I may not have everything in full focus. For the mids and tweets I was looking only at spec sheets from manufacturer. I'm all ears for other options in my price range of between $300-$375 to equip these cabs with nice drivers.
Best Regards To All,
Rich
I have uploaded 3 potential drivers to use in the Pioneer CS-77 cabs. This is going on the plan to redesign baffle as been suggested in earlier posts. Are these good choices? I'm not looking for the absolute highest quality items just solid performers. I was able to run simulation with the Dayton 8" woofer in Winisd and it looks very good to me. Keep in mind I'm very new to this stuff, so I may not have everything in full focus. For the mids and tweets I was looking only at spec sheets from manufacturer. I'm all ears for other options in my price range of between $300-$375 to equip these cabs with nice drivers.
Best Regards To All,
Rich
I have a pair of these I bought in 1969; my first speakers.
I have resisted all request to throw them out.
My plan was to install a small amp to drive a pair of satellite full range and cross over to sub mounted in this cabinet. Wondered if this woofer would work as my driver.
I assumed the rest was beyond salvage.
Love the cabinets.
I have resisted all request to throw them out.
My plan was to install a small amp to drive a pair of satellite full range and cross over to sub mounted in this cabinet. Wondered if this woofer would work as my driver.
I assumed the rest was beyond salvage.
Love the cabinets.
I would be much more interested in crossover changes than a driver change. These are Japanese "Kabuki" speakers which have certain strengths. I do worry about driver rot here, because these seem to be foam surround mids and tweeters, but deal with that when you get to it.
As is often the case here, if you don't do those simple driver impedance measurements I suggested, I am guessing and worse, wasting my time. That's probably a very good bass given a certain rolloff and reasonable second-order filter.
The tweeter looks odd, I'm not quite sure what it is. A cone or a mylar type with a phase plate.
As is often the case here, if you don't do those simple driver impedance measurements I suggested, I am guessing and worse, wasting my time. That's probably a very good bass given a certain rolloff and reasonable second-order filter.
The tweeter looks odd, I'm not quite sure what it is. A cone or a mylar type with a phase plate.
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Thanks Steve,
I't would certainly be a less costly venture then a complete cab/ driver overhaul. Looking at the crossover design and doing simple impedance testing is most prudent place to start. As I acquire more knowledge then take on a more advanced dyi project. Your thought and ideas are much appreciated!
Best Regards,
Rich
I't would certainly be a less costly venture then a complete cab/ driver overhaul. Looking at the crossover design and doing simple impedance testing is most prudent place to start. As I acquire more knowledge then take on a more advanced dyi project. Your thought and ideas are much appreciated!
Best Regards,
Rich
I can show you how the frequency response looks with minimal modification and assuming 8 ohm bass, and 16 ohm mid and tweeter, because it didn't play nicely with 8 ohm versions. Below.
A modern classic flat-baffle three way uses 8", 4" and 1" drivers. Or 12", 5" and 1".
SEAS-3-Way-Classic
A more complex mid filter too, with steeper rolloff at either end in Steen Duelund theory style. Choice of drivers is important. You ideally want efficient mids and tweeters to match the bass. TBH, I'd see what you can do with the current drivers before spending hugely on new ones.
Did I mention to keep the crossover components cheap? A small 33uF NP electrolytic will be fine on the bass. Perhaps parallel two 10W 6.8R wirewounds too for 3.3R. If there is a hole in the midrange, change the 33uF to 22uF to lessen the bass slope. 10W types will be fine for the mid's 1R and 15R. But I would expect this to sound way bassier and cleaner.
Oh, I should mention that the mids' frequency response has to be raised 6dB to really see what is going on. I used TWO mids in series to get to 16 ohms relative to the target response! Just the sort of thing I do when modelling weird and wonderful old 16 ohm speakers. LOL
A modern classic flat-baffle three way uses 8", 4" and 1" drivers. Or 12", 5" and 1".
SEAS-3-Way-Classic
A more complex mid filter too, with steeper rolloff at either end in Steen Duelund theory style. Choice of drivers is important. You ideally want efficient mids and tweeters to match the bass. TBH, I'd see what you can do with the current drivers before spending hugely on new ones.
Did I mention to keep the crossover components cheap? A small 33uF NP electrolytic will be fine on the bass. Perhaps parallel two 10W 6.8R wirewounds too for 3.3R. If there is a hole in the midrange, change the 33uF to 22uF to lessen the bass slope. 10W types will be fine for the mid's 1R and 15R. But I would expect this to sound way bassier and cleaner.
Oh, I should mention that the mids' frequency response has to be raised 6dB to really see what is going on. I used TWO mids in series to get to 16 ohms relative to the target response! Just the sort of thing I do when modelling weird and wonderful old 16 ohm speakers. LOL
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