My neighbor recently bought an NAD 753 and has it hooked up to PSB Image bookshelf 3L/Rs (55-21hz) fronts and PSB bookshelf 1Bs (60-21hz) rear surrounds. We can't figure out how to set the crossover since both fronts and rears are bookshelves with different frequencies. I know HK would allow us to set the crossover for each individual set of speakers with their quad-cross over. What do you do in this case when you don't have full range speakers for the fronts and your rears are smaller? We'd loke to get the full range fromt each speaker if possible.
Getting the full range from each speaker is a bad idea. They are generally pushed incredibly causing more distortion at their bottom listed frequency.
Be smart---these speakers are made for an 80hz crossover to a good self-powered subwoofer. This allows the speakers to "sing" without being pushed at the extremes. The sound you get at an 80Hz crossover should be far superior, as long as you place your subwoofer correctly.
Gman: So what you are saying is to set all speakers to "small" and set the cossover to 80Hz. Assuming 80 sounds good. My friend might as well have gotten all 1Bs and saved himself some money. Am I following your logic? In other words, unless you have full range speakers in the front, you may as well get all the same such as in the Krix KDX system. How do you know 80Hz is where these need to be? Do you have a similar set up? Thanks
I think that is exactly what Gman is saying. The Image 3LR is not meant to be a full range speaker, rather it is to be used in conjunction with a subwoofer. It just doesn't have the drivers for it...and isn't intended to. If you friend was told that these were full range speakers, he was deceived greatly. Therefore, as you say, you MUST set the speakers to "small" and use a subwoofer. As Gman says, 80 hz is a very good place to start. I think that frequency is kind of a good "default" setting for most speakers. You can set it higher or lower, but it is usually better to err on the side of caution and send more power to the sub and less to the speakers as not to push them too hard as Gman says.
The 3LR's will produce a much stronger and fuller sound than the 1B's...so in my opinion, they are much more suited to being front speakers than the 1B's. Your friend should not question buying these (and not getting 1Bs all around as you said).
I have Monitor Audio GR10's that are over $1,000/pr that I set to 80 Hz crossover. And these speakers play down to around 40hz--but I wouldn't say they play optimally down to 40hz.
Your assumption that all speakers sound the same from 55hz to 21hz is way off. Most don't sound anything like each other and very few have flat (even) frequency response graphs against many variables from 20khz to 100 Hz for a number of different reasons.
You are assuming that the quality of the speaker drivers, the crossovers, the internal bracing and rigidity, and overall sound quality is identical in all the PSB speakers between 60Hz and 21Hz. Nothing could be further from the truth. Also, in the smaller speakers the amount of sound that can be projected is normally a lot less.
PSB also sells bookshelf speakers with similar frequency response as those you listed at over $1,000 too.
80 Hz is normally a reasonable crossover spot for many bookshelf speakers because it is usually at the spot close to where the midrange/woofers start to strain and cause significant distortion in the lower range. You can try 100 Hz crossover and see if you prefer it too.
Most speakers list the bottom and top numbers of frequency response as possible. Not as recommended. It is marketting. Most bookshelf speakers sound much better at least 10-30 Hz above their bottom listing.