Marantz 1150 D?

[darkczar]

Hi,

This is going to be an unfocused post. Basically, I tried to refoam (re-edge) my 26 year old Boston Acoustics BA 100's, and utterly failed. Now I'm thinking of getting some new speakers, like maybe these:

http://www.amazon.com/Cerwin-Vega-Xl...pr_product_top

Question: Will my vintage Marantz 1150D power those speakers? The room is 13' x 11' with a ceiling just under 8'.

http://www.classic-audio.com/marantz/1150d.html

Should I refoam the BA 100's again? I did not get a kit with shims, and now I see that you can do the refoaming with shims, which is supposedly foolproof. I replaced the woofers in 1994, so they're not ancient.

thanks,

JP

[mdocod]

I see no reason why that amp could not be used to power those speakers. They are apparently 8Ohm, which is what the amp is rated to handle. The high sensitivity of the vegas should keep your amplification needs pretty low.

[Inductor]

If you buy a second pair you will have the time to send your old speakers for repair and upgrade them with better components (caps) if needed and all.

The differences (I don't know your old BA speakers) you will find besides good monitor loud type sound is not so low bottom end with attenuation at 90 Hz (this being the main consideration) and lesser dispersion than hifi domes with probably a more problematic cheap compression driver with lower range quality to +/-18KHz. The PA drivers if not very good//expensive or pick by hand can have a lot of peaks and dips.

[darkczar]

So, you're saying basically that these Cerwin Vegas are more for a PA, and less for a high end man-cave type stereo system? Am I better off with B&W or Klipsch? I just love the idea of 4 15" speakers, but maybe it's the wrong tool for the job, so to speak?

[picowallspeaker]

Since that Marantz has -like all the Marantz I know - the preamp out / main in outlets , you could search for a second amplifier so youl'll have a dedicated amplifier for the lows and one for mid/treble frequencies .
(take this with a pinch of salt check if the preamplifier is able to drive two amplifiers , for impedance match ...probably you'll need a buffer...)

[darkczar]

How would that work? Take a signal out of the Marantz, and feed it to second amplifier? I could use the tape out, huh?

Would I have to modify the Cerwin Vegas to run the woofers off that separate amp? Sorry for the noobology...

[picowallspeaker]

talking about noobology
Nope , the preamp outlet breaks the circuit just before the signal enters the (input stage of the ) amplifier , so you have available the 'pre-amped' signal ,that is to say, input selected ,tone yes or no,filter ,loudness etc, and VOLUME.
Ideally , a Y type plug would do the job ,sending the signal to both ( or more )
amplifiers . In the real world , impedance at the output of the amplifier should be at least 1/10 of the impedance of the next stage ,otherwise the impedance mismatch would restrict bandwidth . So a buffer is a circuit that allows to have the lowest impedance ; and it can drive almost any load .
For the speaker system side , many manufacturers use double ( or triple or quadruple ,depending on the number of ways of the system ) binding posts that allow bi-tri-quadri amping , and when that is not needed ,they are connected with a wire . They may also serve for BI-WIRING ,a method to split cables from ONE amplifier .
I guess that for a first try and enjoyment of it , an amplifier attached to the preamp out would make a substantial difference ...use the higher power one for the woofers

[darkczar]

I see where you're going with this. You're describing the perfect application for a chipamp! I just need an amp with no tone controls, input selector, yadda yadda yadda.


Hmmm. I've built one so far, with TDA 2050 chips, but I'm not sure it would be strong enough. Is there a chipamp chip that would be appropriate to build the kind of amp you're describing? One that could drive multiple 15" speakers?

[mdocod]

There seems to be some confusion about power requirements here. Generally speaking, larger speakers are more efficient, and will require less power to reach the same listening levels as smaller speakers.

[picowallspeaker]

Yes , though ...larger speakers generally (looking at the magnet and construction ) are dimensioned for high power ...something like ' All you can eat'
Indeed the Pro series include in the datasheets of the drivers the compression
factor at which the driver won't 'trasduce' the power into pressure .
And that limit is often 10-20 dB higher than home hi-fi usage (?!? ).