Altec 510 reviews?

I have a pair of the Altec 510-s speakers (new issue, original owner). I used them in my home theater system and they worked exceptional as large front mains. I used a pair of Altec 201's for the surrounds and a custom center channel using Altec 508 8" drivers and tweeters in a custom built matching cabinet. No sub-woofer at all in this system and it sounded very very good. However, all of the cabinets are large and i have since moved and cannot set them up in the proper room anymore. I sold everything except the 510-s. The Altec 510-s are pretty good speakers in a large room for music. The Titanium mid range and tweeter drivers provide exception detail and the carbon fiber woofers always provided the bass slam when asked too. They sounded best on music with punch. I tri-amped them once to see how they would sound and I was amazed at how much better they performed setup this way. Very dynamic and large sounding, however I could never use these speakers for long listening sessions as the on-board crossovers made way too much phase shift for me to tolerate. If you had an external digital crossover they would probably sound much better if you disconnected the on-board passive unit and wired directly from terminal to driver. Out of the box brand new, they are great for punchy music and HT but not for high end listening. Mine are not hooked up anymore and are for sale if you're interested in trying them out. I am selling them for 1/2 price new and they are in very good shape.

My 510s were bought for $80 on craigslist. They had a lot of cosmetic issues, but worked well. I bought them purely to play with, to see if they were like my old 508s. They couldn't compete with my VMPS RM30s, nor for $80 did I expect them to. When I got done checking them out I gave them to a coworker, who seems to like them. As I mentioned, you're going to need to spend more $ to improve on them, and you are facing the law of diminishing returns, big time.
Because of their excellent "listenability" I thought they were good enough to keep long term in an above average system, which is high praise for me. You've got a pretty good speaker; you might consider staying with them. They need a gutsy amp to get them going.

Thank you for your response Jmbatkh. I really appreciate your taking the time. I am happy with the 510's and know that reading through all of the information here that I could do better to be sure that all other components of my system are up to par. That will allow the speakers a chance to perform to their optimum. Diminishing returns is also a good point. At what point to end the pursuit? It could be a long road. I hear so many technical issues brought up here and in different threads that I don't know what to make of half of it. That is, I don't know if I could detect phase shift and other technical occurances unless this auditory situation was pointed out to me. For that reason and others I think I would have to be in a training session with a sound engineer to understand and hear all of these differences. Again, appreciate the response. You have been helpful!

I have 604 based speakers which are in enclosures built by Serious Stereo. I disagree that they do not sound full or open at low volumes. I suppose it would depend on the implementation of the speaker though. Mine are in a 11.5 cubic foot bottom vent enclosure. I normally listen around 70-80db and they sound very good to me at this level. They still sound good at lower volumes but I think you will find that most all speakers will need at least this much volume to sound their best.

Can anybody help me with the crossover frequencies of altec lansing 510 A speakers? Thnx.