Another Bose 901 restoration thread

[leesonic]

Wow! I didn't think anyone was still reading this thread. I've already repaired it, I cut the damaged piece out, glued in a new piece of wood, filled it, sanded it, and put a strip of veneer over it.

Lee.

 

[dennismiller]

Of coarse we are still following the tread. Interesting and useful info! Looking forward to the final completion pictures.

 

[zenarrrow]

I won't lie, I am scared Hahaha. So please forgive any apparent elementary questions I may ask. I am new to all this but look forward to rebuilding amps and refoaming speakers and stuff. You say you did not use the test tone cd in your repair?

 

[leesonic]

OK then, here are a couple of pictures of the repaired area. The veneer was supplied by @MAXZ28 (thank you) and is almost the same as the Bose veneer. These pictures were taken after the rub down with 220 grit and first application of Tung oil. Then came the 400 grit (did that tonight), then will come the 800 grit, and a final rub down with fine steel wool. I did think about leaving them outside the next sunny day we get, maybe the veneer will darken up slightly.

 

[Rick Vestal]

Wow... I think I would have lost my sanity by this point... Are you sick of yogurt yet? lol

 

[R-2-R]

Bose 901 restoration project

Was it difficult to remove the speaker grill/cloth (or whatever you want to call it) from those 901 speakers?
Exactly how did you remove it, could you explain in detail?
Were 'staples' or glue, small nails, etc. involved?
Are you going to replace the grill/cloth with the same/original one's or are you going to create your own?
Thanks for posting pictures and sharing your experience with this project. You sure have made those Bose 901 speakers look great! Your talent shows big time. Wish I had the time & space but most important the knowledge and expertise for stuff like that.

**EDIT: Are all 901's cloth/grills stapled? Where exactly would one start at, on the speaker that is they obviously are hidden, if they wanted to remove the cloth/grill that is stapled?

 

[js1138]

The IV grills are stapled. You remove them with pliers and maybe a sharp screwdriver to get them started.

I never got around to re-stapling them. I'll probably use Velcro.

 

[leesonic]

Thanks for posting pictures and sharing your experience with this project. You sure have made those Bose 901 speakers look great! Your talent shows big time. Wish I had the time & space but most important the knowledge and expertise for stuff like that.

The sad part is, I can see me selling these because I don't want to spend another $150 on the equalizer to hear whether they sound good or not. They sound awful without it, like using a "regular" speaker without a crossover. For these, the equalizer IS the crossover. It boosts and cuts frequencies as the Bose engineers intended, easier to do with low level signals.

Lee.

 

[R-2-R]

The sad part is, I can see me selling these because I don't want to spend another $150 on the equalizer to hear whether they sound good or not. They sound awful without it, like using a "regular" speaker without a crossover. For these, the equalizer IS the crossover. It boosts and cuts frequencies as the Bose engineers intended, easier to do with low level signals.

Lee.

Oh yes I definetly know all about that! I have four 901's Series V speakers and a pair of Bose 802's Series II speakers. As for my Series V speakers Active Equalizer well all four run off just one Active Equalizer which is just great. The 802's have their own that they run off of.
Don't give up! Keep looking for that Bose Active Equalizer (again, what Series are those 901's that you are restoring?) but keep in mind to look for the 'exact' same Series model as the 901's are. Just wait and one will become available at a reasonable price. Don't let your hard work go to someone else!

 

[adam-ads]

The sad part is, I can see me selling these because I don't want to spend another $150 on the equalizer to hear whether they sound good or not. They sound awful without it, like using a "regular" speaker without a crossover. For these, the equalizer IS the crossover. It boosts and cuts frequencies as the Bose engineers intended, easier to do with low level signals.

Lee.

I think the eq curve has been posted here before. I'd try to recreate that curve in Audacity and apply it to a few demo tracks.

 

[adam-ads]

Eighteen rotted surrounds in the Bose, eighteen rotted surrounds
You take one down, you paste it around
Seventeen rotted surrounds

 

[leesonic]

OK, so I finally got both cabinets restored, and sat down to install the drivers. I decided to re-wire them while I was at it, since I didn't like the look of the bell wire that Bose used. I had to enlarge the holes inside the cabinet for the thicker wire, I used a Milwaukee 1/4 in. Hex Offset Drive Adapter (get one at Home Depot Model # 48-32-2100, Store SKU # 105269) and a drill bit with a 1/4 in. hex shaft. The wire wasn't anything fancy, just some 14 gauge I had lying around.

I figured I'd start by re-wiring the two terminals that I could see through one of the speaker holes, and work my way around. This proved to work out perfectly, as you'll see. When I refer to the speaker numbers, number 1 is the lone driver at the front, and the others at the back are 2345 going across the top from left to right, and 6789 are across the bottom.

So here are speakers 6 and 7, with new wires soldered on, waiting to be mounted back in the cabinets. Soldering wires onto these drivers is not a problem if you are good at soldering, just scrape the terminals clean with a razor blade. This is the only place I used the correct colored wires, everywhere else the wires are black. I did however put a piece of red heatshrink onto the wire as it went through into the next cavity, just to remind me that it needed to go on a positive terminal.



Here are 6 and 7 mounted, with the speaker turned upside ready to work on 2 and 3. The one saving grace of the Bose gaskets is they can be stretched over the drivers after soldering the wires on.



2 and 3 soldered.



Then around to the front and solder number 1. The weird part here is on the Bose wiring (written on the back of the driver) it has a red wire soldered to a negative terminal on the speaker. I duplicated this, since the red wire goes through and connects to number 4



4 and 5 soldered. Can you see my repair on the left edge here? No? Good!



Lastly, 8 and 9 soldered.



Here it is, all back together. The front baffle on this speaker was a little faded for some reason, so I colored it back it with all things, a giant Sharpie marker. It's a shame Bose didn't design these speakers to have removable grills, maybe they would have put more thought into the appearance behind them? It's kinda gross with all the black sealer all over the place.




I now have an equalizer, so I can finally hear these things as they were meant to be.

Lee.

 

[R-2-R]

Mission Complete?

Excellent, just excellent!
Now hopefully when everything is connected, placed right and setup you'll get favorable results?
Let us know how they sound.

 

[MAXZ28]

Lee,

If the repair finish still bothers you, use a little Minwax Red Chestnut stain on it before the tung oil. It will give it more of a matching color.

 

[leesonic]

Finally got these into the "listening room" (spare bedroom). This meant moving out several pairs of speakers in order to get the Bose standing correctly on their stands. They are still in the corners somewhat, but this is unavoidable given the layout of the room, there is a large dresser with the equipment on it that the speakers sit beside.

I wasn't sure what positions to set the equalizer on, so I just set the bass and treble controls mid-way. I didn't know if this was like the mid point as on most bass and treble controls.

Loading up DSOTM (what else?) in the CD player, I turned the volume up to about number 4, and sat back. The CD player is a Kenwood multi-changer, I use this because it has a 1-bit DAC, which I figured is like my Philips CD840 Bitstream (which is 240v only). Amplifier is a NAD 3240PE.

So, Floyd starts, and I immediately hear the heartbeat at the beginning. It sounded like someone was banging on the side of the house, I couldn't believe the amount of bass that was coming from those little 4-1/2" drivers. Then, as the crescendo peaked, I was blown away by the sound. I sat and listened to the whole album, something I rarely get the time to do on my one day off, so these speakers must have been doing something right.

Lee.

 

[R-2-R]

Success!!!!!!

Mission Accomplished!
Now final question, are you going to keep these or sell them?:scratch2:

 

[leesonic]

I'll probably sell them, since I have more speakers than room, amplifiers, or speaker wire. Did you see the "wall of speakers" post on Barter Town?

I thought about putting them up on Barter Town, but I don't seem to be having that much luck on there. I would have listed them on eBay this Sunday, but I need to strip and paint the Bose stands, and it's snowing here right now in South Jersey...

Lee.

 

[zenarrrow]

I followed your lead and finished off my refoaming on my 901 IV's. I bought a EQ for the pair hooked them up and seems to sound really good.... Except for the fact that I am picking up radio waves now. Only through the left channel, and only when I do have the EQ on as I tried running them just through my Pioneer 980 SX.

So, my first question will be what exactly does the EQ do in the first place? I sure can tell a difference. I will not hide the fact that I am real new to this. So if this is elementary please excuse me.

Second, How can I stop these Radio Waves? I hope I do not have to go throught the damn thing and rebuild it....after refoaming the speakers.

Billie

 

[PioneerGuy75]

Nice!!

 

[leesonic]

I followed your lead and finished off my refoaming on my 901 IV's. I bought a EQ for the pair hooked them up and seems to sound really good.... Except for the fact that I am picking up radio waves now. Only through the left channel, and only when I do have the EQ on as I tried running them just through my Pioneer 980 SX.

When you say Radio Waves, do you mean you are picking up an FM station or something? If you only get it when you have your EQ switched in, that's your problem right there. You might want to start with some better shielded interconnects. The Bose EQ has a wooden case, not exactly the best at keeping out interference. I wonder why only the left channel though?

So, my first question will be what exactly does the EQ do in the first place? I sure can tell a difference. I will not hide the fact that I am real new to this. So if this is elementary please excuse me.

The EQ boosts the bass and treble, put simply. You'll hear the difference when you switch it in and out. It was they way Bose decided to give the speaker a flat response, otherwise it's all midrange as you'll hear without the EQ switched in.

Lee.