fill35U

Danny Phantom's "ghostly wail", Bolt's "superbark"?

Linking to trailers for *those* would certainly increase traffic to the site... To keep things topical, how many superheroes/villains use sound or hearing as a power? Daredevil comes to mind.

Congrats on getting them up and running! I don't think you'll hurt them by driving them harder, at least with unclipped music signals. Don't forget that EQ is cutting out a lot of the mids, and boosting the snot out of the highs and lows! They would probably sound a *lot* louder without the EQ. Here's a chart you can't find on the Internet. EQ curve for a Series VI: I won't argue that the IV's have a *different* EQ, I know the V's are definitely *slightly* different. But given the similarity of the drivers, III's and IV's should be *pretty much* the same. In any event, look what the user-adjustable controls can do to the response. In theory, those controls are there to help you compensate for the room (presumably floor bounce and wall reflectivity). I don't think the EQ would clip at the input buffer from too high a level- its got +/-15 V supplies. But with 15dB of boost at the first stage, I could see it clipping "along the way". And with better than 20dB of boost available overall, it won't take much at 15kHz to cause problems!

Hi Brian... I have a set of BOSE901 series II. I'm assuming the newer versions follow the same build parameters although with newer drivers and equalizers. I believe the Bose901 drivers are 6-8 ohms each and thru use of proper series/parallel circuit wiring will ultimately show a 6-8 ohm total load to the amplifier. They are not 1 ohm each. Be sure to follow the internal wiring connections within each cabinet. Series I & II used 8 ohm drivers, wired as three parallel strings of three drivers in series each: The drivers in Series III through VI are nine 0R9 drivers in series:

IMHO you'll be fine with the later drivers. Due to the nature of the beast, I'd put your best two drivers in the fronts. In practice, I don't think you'd notice much difference swapping drivers or EQ between Series III-VI.

There are plenty of used drivers on eBay. I don't think the Parts Express drivers have the HVC (edgewound aluminum ribbon voice coils), so efficiency, power handling, and high frequency response might be reduced. In addition, they have stamped steel baskets instead of the injection molded ones. And I believe the factory coated the back of the cones starting with Series IV. Enough things different that I don't think the PE drivers would be equivalent or an improvement. If it helps, here's the page on diagnostics from the Series VI service manual:

Thanks for posting pics, Brian! 18 drivers to refoam- your task lies ahead of you! BTW, the Series III and IV were most susceptible to foam rot. V's and VI's are much more resistant. And of course I's and II's used cloth surrounds.

We don't *all* hate *everything* about Bose! Like any other entity, they didn't do everything right, but they didn't do everything wrong, either! If you mean what I think you mean (running more than one pair of 901's for front left & right), then yes, you will only need one Active EQ. You should be able to split the signal, a Series IV EQ can drive down to a 5K impedance. Keep in mind that the Series III and Series IV shared the same EQ curve, as did the Series V and Series VI. But there's not *that* much difference between III&IV and V&VI that I'd lose sleep over mixing, matching, or sharing EQ's between those models. Heck, I knew a guy who used a Series VI EQ with his Series II, and we thought they sounded great! You can add any other EQ's or processors that you like. I would put the Bose EQ *after* anything that does dynamic adjustments based on frequency content. You can even try replacing the Bose EQ with your own, but it's a surprisingly tricky curve to replicate, and I think the phasing of all the filters Amar daisy-chained may be significant. Amps choice? Whatever you want! I don't think you can hurt them. Heck, I plugged one into the wall socket once. Here's your warning: it was *LOUD*. An M-1.0t MkII Opt 2 for each speaker would be sweet! With no passive crossover, and 8 ohms per speaker, they're a relatively easy load. Put the Crown to work on a pair of sub's and the 901's won't have to work so hard. I've read that the cones break up (acoustically) around 55 Hz, and Bose is already forcing them to work well below their Fs. There's that headroom advantage to biamping, too... BTW, you've got a serious collection of serious amps there! The Klipsch Forte's are very nice, but the 901's are a completely different approach. Each has their pros and cons. Have fun!

I'll add that my receiver, a venerable HK AVR210, allows for the front main speakers to be sent not only the full frequency range for their channels, but also the LFE channel mixed in. It also allows the sub channel to handle either just the LFE, or the LFE mixed with the lows from the front main speakers as well. I would hope that newer receivers and processors give similar options.

Welcome to theCarversite, Steve! Nice amp! But in the brief time you've been here, I'm sure you've discovered how addictive Carver gear is. We look forward to seeing the other components that you're going to acquire. And good work finding Steve an amp, Gene!

Well, I *plan* on using four, as soon as I find the time to build them! FWIW, I don't think there's anything magical about stereo subs, so much as using multiple subs can bring room modes under more control (with proper placement). That said, easy enough to see if there's a significant difference: feed them both a combined mono signal, and compare to the stereo performance. I'd be curious about the results!