[rellim68]

Hi all, Would  it be  better to buy another 4B & run it mono with the one I already have or is the better route to Sell the 4B and look for a set of 7B's. Money is an issue an I thought buying another 4B  might be the cheapest to be frank , I don't know what the difference would be ,so any help would be great(. note I am talking 1989 vintage 4B's)

[jethro]

If power is not an issue, then the cheapest and most practical solution would be to sell the 4B and buy a 4B-ST. If power is an issue then you could buy a 4B-ST, keep your 4B and bi-amp the speakers. If you can't bi-amp, and need the power then the 7B-ST would probably be the next option.

If the nominal impedance of your speakers is less than 4 ohms then bridging a 4B or 4B-ST would probably not be a good idea.

Please post you speaker type so we can give a better answer.

[rellim68]

The speakers that I am currently using are athena AS-F2 , these are an 8 ohm speaker. My pre amp is an hafler 915. Can you explain bi-amp , my thought was to use one 4B for each speaker

[Fife12]

I think Jethro is assuming your speakers have two sets of binding posts which allow for bi-wiring.

If so, he probably means to use your existing 4B for the bass drivers on your left and right speakers and buy a 4B ST to use for the high/mid drivers resulting in bi-amping.

Of course you would need 2 pairs of speaker cables instead of your original one pair.

Im not familiar with your speakers but I would follow what Jethro suggest.
Sell your 4b and get a 4B ST if power is not an issue. Otherwise, buy a 4b ST to biamp.

[jethro]

The 4B that you now have should be more than adequate for driving your speakers. Buying a second 4B and running them in bridged mode will not give you any improvement in sound, and might degrade the sound. Personally, I would try to audition the 3B-ST, 3B-SST, 4B-ST and the 4B-SST with your speakers to see how you like each model. All of these amps probably have enough power to drive your speakers, and it really comes down to your preferences and the sound/price of the different models.

Bi-amping is only posisble when you have two sets of binding posts for each speaker.  The pair of binding posts are usually connected with a gold plated plate and connect the high frequency and low frequency portions of the speakers crossover. When you bi-amp, you remove this plate and use separate amp channels to power the high and low frequency binding posts. This is not the same as running in bridged mode. Some people use differnt models of amps for the high and low frquencies, and some people just bi-amp to gain more power by adding another amplifier.

[rellim68]

Thanks for your quick replys, guess I just don't know what I want , or should I say I want some thing better.Perhaps  my best course of action is save my money . unfortunate but I have to leave town to audition gear like the bryston line.

    PS my speakers only have one set of binding posts  bi amp not happening.

[jethro]

To clarify a bit, I'm pretty sure from the Athena website that you cannot bi-amp your speakers which is not a problem.

You also only need one amp, whether it be a 4B, 4B-ST, 4B-SST, 3B-ST,  or 3B-SST.

[rellim68]

Again thanks for the friendly advice, I am hopeing my new  pre amp ( hafler 915 ) will be an improvement over my very vintage NAD 1020A.Perhaps this change will keep me satified for a while. I have been trying to get a .4 line stage but the bidding usually goes above my cash reserve , I got the hafler for a REAL good price, does anybody use one with there bryston gear by any chance

[Uptown Audio]

I would suggest replacing the Hafler preamp with a BP20. The 4B amplifier is more than plenty of power for almost any set of speakers. Replacing the preamp will get you better sound, not just more power. The BP20 and BP25 are significant improvements over their older preamps.
-Bill