Separate amp for Bose 901

[captbill]

Would it be possible to use a unit like Yamaha HTR 5890 and use the front speaker outlets to a separate amp like my old and good Yamaha a720 to power my Bose 901's in a home theater set up. Thanks, Bill

[jcPanny]

Probably not advised. Since Bose does not post specs on their speakers, I am not sure what the power rating is for the Bose 901s but your Yamaha should be more than enough. If you want to improve the audio quality of your setup, speakers would be the best investment.

[DaveOCP]

Considering the 4" paper drivers involved, I'm guessing the 901s are not fond of a whole lot of power. Consider other speakers, any other speakers.

You can now buy speakers very cheaply that incorporate multiple drivers specifically designed for different frequency ranges! Apparently its all the rage these days.

[Resident Loser]

Would it be possible to use a unit like Yamaha HTR 5890 and use the front speaker outlets to a separate amp like my old and good Yamaha a720 to power my Bose 901's in a home theater set up. Thanks, Bill

...from one amp to feed the inputs of another is not a good idea...it's not that it can't be done, it will require choosing the correct values for a voltage dividing network, it's just not a particularly good idea...although auto-sound system installers use them for head units not equipped with pre-outs to feed outboard amps.

I assume the Yammie doesn't have "pre-outs" nor is it equipped with a true "tape mon" circuit to accomodate the 901s EQ.

Just a bit of info for all the know-it-alls re: the Bose 901s...Series I and II(acoustic suspension design) could handle 270 RMSWpc and worked best with amps rated @min of 100Wpc...the later vintages can still handle the top number, I believe, but require only a min of 10Wpc due to their ported design. They have nine 4.5 inch fullrange drivers per cabinet...each has a max excursion of +/-1/4 in. and a total radiating area of a 12in. woofer...when properly set-up they can kick butt in the bass dept.

jimHJJ(...of course they may not be to everyone's liking...)

[Blundaar]

Considering the 4" paper drivers involved, I'm guessing the 901s are not fond of a whole lot of power. Consider other speakers, any other speakers.

You can now buy speakers very cheaply that incorporate multiple drivers specifically designed for different frequency ranges! Apparently its all the rage these days.

That's a good one!

[Resident Loser]

Would it be possible to use a unit like Yamaha HTR 5890 and use the front speaker outlets to a separate amp like my old and good Yamaha a720 to power my Bose 901's in a home theater set up. Thanks, Bill

...got the opportunity to check the Yamaha website this AM and, good news...you are good to go...you do have pre-outs...simply feed the receivers front "pre-out" to the 901s EQ "in" jacks(NOT the ones labeled "tape mon") and the EQs "out" jacks to your outboard amplifiers inputs. There is a downside, you cannot connect a tape deck to the EQs "tape mon" ckt since the signal here will not be at a fixed line level and using 'phones or others loudspeakers connected to your A720 is also no-no. The EQ will always be in the circuit and the bass increase might damage them.

Couldn't find any specs on the 720 so I'm not sure of it's power rating compared to the advertised 140Wpc of the HT unit. IMHO, having an outboard 2/ch amp with it's own power supply, chassis, etc. (as opposed to sharing it in a multi-channel unit) couldn't hurt...I have no concrete reason to support this, it's just a personal preference.

jimHJJ(...hope that helps...P.S. ignore the comments of the uneducated...)

[captbill]

Boy, this is interesting, Bose sent thier compatability chart and they say the Yammie 5890 would not work with my 901/IV series, so in the meantime I picked up a Yamaha DSP-A1000 that has pre in an outs. I bought it off EBay, something I rarely do. This should work until I get things sorted out. All the Bose recommended receivers for 901's are 2 and 3 thou. I know a lot of people don't like 901's, but properly set up they can give very good sound.I am used to a separate unit set up so researching this all in one is new to me, Starting to see post's about the Yammie 5890 overheating. The wife decided we need to replace the 46" Hitachi, so I'm going to go with a 50" Panny plasma that does'nt have speakers. This site is very informative, didn't know it existed till the other day. I still have some Mcintosh stuff, but being retired it's to exspenve for me now. The Marantz stuff has been downgraded into the garage, still plays good though. I've had Yamaha stuff for years now that works great. The Yamaha A720 is 105 watts per channel at .005THD or150 watts DIN/ channel , the recommended power for the Bose/901/IV, 10 watts/channel at 8 ohms, no power restrictions for max power.Thanks to all who have taken the time to answer. Ciao, Bill

[highfihoney]

hello,i agree with bose 901's being able to sound good,obviously placement is a factor but amplification play's the largest role with 901's,you know what i find very odd about bose is that they used to make 2 different model amplifier's for specific use with the 901's but for some reason they decided to stop making amp's with enough wattage & current to effectivly drive their reference speaker system.

the 2 bose solid state amp's were the model 1800 & model 1801,both would work fine but are a little hard to find in decent shape plus they are very old,it would be easier to reccomend proper amplifiaction if you gave us a budget.

what i found to be most important with the 901's i had was not only enough wattage to push them but the higher the current the better,bose also under rated maximum wattage capabilitie's drasticly with the 901's,they can easily handel twice the power as long as it stay's clean or if the amp has a soft clip feature.

out of curiosity what mac gear do you have,if your mac gear isnt powerfull enough to drive the 901's you may want to think about selling the mac stuff & reinvesting the fund's into your new amp's allowing you a larger budget.

the resale price's on most mac gear is very good & on select model's such as the mc240 & mr78 they have gone through the roof,if you list the model's & their condition i can give you a ball park resale value if your interested.

[Resident Loser]

Boy, this is interesting, Bose sent thier compatability chart and they say the Yammie 5890 would not work with my 901/IV series

...it won't as it has neither "tape mon" facilities or a corresponding "power in" to go with the "pre-out" jacks...

Using it strictly as a pre-amp to your A720 it's OK...

jimHJJ(...no problemo...)

[captbill]

The Yamaha DSP-A1000 has pre main in and out jacks so I'll be able to hook up the 901's. The Mcintosh C225 amp I used to use on the 901's had a tube go out and I was outside the U.S. at the time so I picked up the Yamaha and used it to drive the Bose's. The Mcintosh stuff is in a Barzilay cabinet, with the Barzilay speaker cabinets using SP 12" speakers. that's the living room gear. I used to blow speakers all the time in the old days with the Mcintosh.The Yammie has all the class "A" switch's and stuff and has been a fine unit. My tuner is an Mcintosh MX110, which I don't want to sell at his time. I also have Marantz gear, a 120B tuner that has a scope, and in the garage Marantz 1070 amp with a Sansui tuner with Sony speakers and woofer. I had huge Akai speakers in the garage but they started to have that base burr at times so hence the Sonys.Also in my den with the 901's there are 201's in the rear with a Bose VCS-110 center channel speaker in front. Set up correctly, with "power" the Bose 901's are OK. With all this new stuff out here it is facinating sifting thru the usual salesman hype etc. Good learning experience. Have to figure out how you people list all that equipment under your monicker. I'm drooling over that Mcintosh stuff, must keeps things in balance though, although I just remembered I have to spend money out of my IRA, finding this site, hmmm, Thanks again, Bill