# Playing with the Fisher St-828's



## the_diyr

Ok the drivers and crossovers are all messed up in these ..The 15 inch woofers appear to be in good shape as does everything else they just sound awful.. So I did som enclosure calculations on this three way box , it has enclosed mids and tweets that take up hardly no space in the enclosure .. The enclosure in cubic feet is 2.648 ft³.. So the port in these is 5 inches long by 2 inches round.. So I did some calc's and came up with a low freq somewhere in the neighborhood of 23-24hz.. Wow..My only problem is the crossovers that were in these do not work .. .. So I am lookin at replacing the tweets , the mids and I guess the woofers.. Biggest thing that gets me about the 15 inch fisher woofers is with a real bassy song they produce great bass but they barely move.. I guess if i replace the woofers I will get better sound because these speakers are at least 25 years old.. I got them at a garge sale years ago for 12.00 for the pair.. They are 27 inches tall , 17 inches wide , and 13 inches deep.. 8Ω


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## the_diyr

:dontknow:Here are some crossover ideas if i build my own.. What was normal for the speakers that were in the cabinet was 1.5 - 6 khz... So I used the calc for first order , and fourth order .. Not to sure but 1st order has no gain and 4th order has a 2.99db gain but it will be a monstor to build


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## the_diyr

http://www.diyaudioandvideo.com/Calculator/APCXOver/

This is the calculator I used

Capacitors
C1 = 3.31 uF
C2 = 29.88 uF
Inductors
L1 = 0.19 mH
L2 = 1.7 mH


750 to 6000 here


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## the_diyr

Here is a humdinger 4th order 2.99db gain

Parts List

--------------------------------------------------------------------------------
Capacitors
C1 = 1.77 uF
C2 = 3.51 uF
C3 = 22.24 uF
C4 = 31.42 uF
C5 = 4.71 uF
C6 = 1.05 uF
C7 = 41.92 uF
C8 = 9.48 uF
Inductors
L1 = 0.13 mH
L2 = 0.59 mH
L3 = 0.84 mH
L4 = 4.8 mH
L5 = 0.39 mH
L6 = 0.18 mH
L7 = 3.18 mH
L8 = 1.6 mH

4th Order Normal Polarity

6000 Hertz / 750 Hertz

8 Ohm Tweeter / 8 Ohm Mid / 8 Ohm Woofer
2.84 db Bandpass Gain, Spread = 8 : 3 octaves


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## the_diyr

Ok this looks like the verdict .. I am going to build my crossovers.. Getting the goods from madisound.. I figured it out on a sheet of paper but the photo shows the idea .. Total cost for mid line caps and inductors is about 23.20 per ( Speaker ) Crossover so 46.40 for the pair..:yikes::clap:

I just hope I picked out the right types Went air on the Inductors and poly on the caps....


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## the_diyr

Cost per each and speaker size


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## the_diyr

Is it just me are did Caps and Inductors really jump in price .. Just doing some figuring for a 3 way crossover .. ( 1ST ORDER ) I am looking at 18.00 a 3rd order Normal somewhere in the neighborhood of 40.00 per each ... I am seriously considering these

http://www.parts-express.com/pe/sho...w=1&&vReviewPage=2&vReviewRand=473751#reviews


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## the_diyr

Found some crossovers 800/5000 I ordered them .. 3 way... 

Found some nice 3 inch tweeters polycell , just like my center channel has

and polk audio 5 inch closed back midrange.. Will finish these next week


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## the_diyr

I am debating as to what to do with the front setup...First I thought about building a shelf system around the big screen tv.. But that was sort of shot down by the wife.. I think she sai we dont need anymore clutter in the den..So then I thought maybe build some tall and less wide front speakers .. My biggest problem is the width of the room . My right channel front is just fine but my left channel front is almost behind the couch..and the sub is right on the floor too.. bothe behind the side of the couch..


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## JCD

the_diyr said:


> I am debating as to what to do with the front setup...First I thought about building a shelf system around the big screen tv.. But that was sort of shot down by the wife.. I think she sai we dont need anymore clutter in the den..So then I thought maybe build some tall and less wide front speakers .. My biggest problem is the width of the room . My right channel front is just fine but my left channel front is almost behind the couch..and the sub is right on the floor too.. bothe behind the side of the couch..


I haven't had time to look in much around here lately, so I just saw this thread. I'm confused at what you're trying to accomplish at this point.
_Posted via Mobile Device_


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## the_diyr

Ok I have the crossovers on the way for the ST-828's that merely came with a junk setup for the actual crossover network.. The 15 inch woofers are in good shape even thought they are ugly as .. Now the mids and tweets are all screwy one speakear has the original tweeter and midrange and the other has a slightly smaller tweeter and a slightly larger midrange that was rigged up in the cabinet before I got them.. So I need tweets and mids both closed back design.. Just dont have the cash to get good tweets and mids now .. So I guess i should wait to put the crossovers in..


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## evilskillit

Best of luck, let us know how it works out. I tried to restore a pair of old Galaxy TS80s that had rotted surrounds on the 12" woofers and the passive radiators on the back had completely fallen off.

Never could get them to sound good. Knowing what I know now I probably could get something going, however I pulled the new 12s back out and put them in something else. At least it wasn't a total waste


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## the_diyr

yep I thought about buying ne speakers for the front but most of the new stuff is overpriced plastic junk. I went to best buy and asked the store manager if they had any floorstanding speakers that were made out of real wood .. He laughed and said I dont think they ever made speakers out of real wood... If I cant get the Fisher speakers like I want them I will probably build my own new ones.. I did listen to a few sets of cheaper floor speakers and nothing really struck me as too the type of sound that I wanted.. I even listened to bose at a dealer in town and at very low volume they sound good but when you turn it up it sounds like my grandmothers old am transistor radio... I always knew bose was for old people who didn't know what sound quality was.. Well I think the crossovers will be here today I hope.. And I think the surround repairs for the RSVIDEO center channel will be here tommorrow


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## the_diyr

Ok I ordered some soft dome tweeters for the fisher's to match what is in the RSVIDEO center channel .. Fluid cooled soft domes... I hate waiting on stuff to show up in the snail mail..


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## 1Michael

Crossovers have to be designed and tested with the specific drivers that are going to be used in a particular box. It kind of looks like your throwing some drivers and crossover parts together in the hopes that it will work out? Or am I missing something?


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## the_diyr

Pretty close but I ordered th Cerwin Vega crossovers .. I used a crossover calculator , volume calc is right on the money .. Using CV tweets CV Mids and CV woofers.. The 15 inch woofers are CV's from an old set of speakers.. The cabinet size is perfect for the drivers.. the tweets are closed back , the mids are closed back.. the crossovers are the same specs as what is on the fron of the fisher cabinet



a modest 1.2 -6.0 khz


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## the_diyr

I noticed on all the speakers that are mounted in the ST828's there is no seal.. They are all just mounted to the wood.. I was thinking when I put all the drivers back in i am going to use some rope caulk or something to really seal the speakers good .. I used this on my custom under the seat sub box I installed in my crewcab and it makes a good seal..


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## evilskillit

Bleh to rope caulk. It works great but not if you ever want to get the drivers back out without destroying them or the box. I bought the Dayton BR-S1 kit, which came with rope caulk. After putting them together I wanted to double check the crossovers to make sure there were no problems, but even after shoving a broom handle through the back and pressing on the back of the driver about as hard as I dared to, I could not get it out. Fortunately I think I got everything right, after they broke in they sounded pretty good. But had I not I would probably be screwed.

On my next build I just put a small bead of silicon, smoothed it with my finger and let it dry, it made a nice rubbery seal. Weather stripping tape works well also from what I hear.


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## JCD

This is my preference..










Creates an airtight seal and helps to isolate the driver from the box to some extent. And is MUCH cleaner and easier to install. And it's relatively cheap.


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## the_diyr

Closed cell foam tape is a good idea .. On the silicone thing I heard that it might hurt your surround foam from the fumes .. not sure though.


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## evilskillit

Silicon can, as it offgasses while curing from what I have heard, but if you put it on and give it a few days to cure I believe it becomes completely inert. I could be wrong tho, if so someone please correct me. Tho if that is the case I'm sure you could do the same thing with latex based caulk.

I like the idea of the closed cell foam but sometimes getting it to conform around the edge of a circular hole, especially a very small one can be a bit tricky. Also when you are trying to get speakers flush mounted and are trying to be very exact how does one take into account the extra thickness added by the closed cell foam making the speaker stick out of the hole just a hair more?


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## the_diyr

Well the UPS guy just showed up a few minutes ago with my new Cerwin Vega Tweeters .. So now the ST828 build is going to happen ... Now after a ton of measuring and figuring the old ST828 enclosures I am pretty sure I can make the tweets mids and 15 in woofers work just fine.. Basics are 15 inch CV woofers ( 5 inch CV mids ) and 3 inch CV tweets.. The tweets and the mids are closed back .. Leaving me a cabinet 27 inches tall by 12 inches deep by 17 inches wide.. Port is 2inches dia. by 4 inches long. Box volume is 3.18 .. tuned at about 45hz or close.. May play with the port a little ?? the drivers are the same size as the old fisher drivers .. I am using the CV crossovers as well.. they are 3 way.. I think it will work .. I have played with box and port calcs. before when I designed my 10inch pioneer ported under the seat box for my Ford Crewcab FX4.. Will see tommorrow , If my wife will allow me to work on them tommorrow I meant..:rant:


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## the_diyr

Here are the tweeters and the mids that are going in the fisher cabinets. along with the crossovers.. Just trying to decide about the fisher 15's still in the cabinets , they seem to be in better shape than the 15 inch CV's that I have.. The CV's nead refoaming .. but the fishers do not..


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## the_diyr

They are built // The crossovers were mounted as were the tweeters and mids .. My old fishers sound great.. The cut off points are very smooth.. The tweeters are not the dome type that I wanted but money is a little tight The crossovers that we feared would sound bad actually sound really good .. Now I really want to build some speakers so I am thinking start with something simple like the rear surrounds... Also I still have to build my equipment rack..


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## the_diyr

Ok they are ugly bu they sound great


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## the_diyr

I know the woofer looks like cr** but it sounds good.. Actually I have never be able to make those 15 inch woofers even begin to move .. I tried one time and got my Pioneer A/V reciever pretty loud and still nothing , they do vibrate a little bit ... Maybe one day I will build some better fronts but for now they sound great .. The RSVIDEO infinity that i rebuilt the surrounds is set to small on the A/V reciever and it works great since it is set to small it has no bass at all so it sounds good.. I did have to set the fishers to large and then this made the sub go to plus .. Which all sounds good ... the only thing i would change if I could afford them is maybe replacing the cv tweets that i bought with some ribbon tweets , the only problem with ribbon tweets is they are overpriced for what they are and the power handleing isn't very good


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## the_diyr

Would you set the front speakers to produce dialogue as well as the center since they are larger speakers ????


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## Yad

hi everybody. Please, could you tell me where to buy FISHER STE 555 speaker system ?


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## the_diyr

I found fisher STE 5 Speakers 

http://images.google.com/imgres?img.../images?q=FISHER+STE&hl=en&safe=off&sa=G&um=1


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## Yad

Geee ))) Thanks. :T


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