Help: AM antenna and AM reception


Hello all: I would like some suggestions and advice on AM reception. I know this may not be a popular format but a couple of the stations I enjoy broadcast in AM only.
My experience with AM reception using the "mainstream" FM/AM tuners has been very dissapointing (said tuners being JVC FX1010, SONY SA5ES and Denon TU-800). I tehn bought the Denon TU-680NAB (supposedly optimized for AM performance) but still no luck. OTOH, a pre-wired whole house intercom system with am/fm radio does a FAR better job with the AM stations! This creates a problem with my spouse who says that I spend so much on tuners which are unable to compete with much cheaper syatems! So, what gives? Why does a $300-$600 tuner fail miserably while an "el cheapo" combo am/fm/intercom does so much better? I should say that the antenna used for separate tuners has been the Terk AM indoor type. How do I improve upon this? My location is central NJ. Thanks.
PS: Do let me know if I need to provide additional info.
upgrade1394
The really good AM radios were build before FM became the dominant format. Get an old Stromberg Carlson from the 30's or 40's, and you will hear what AM is really capable of doing. Except for HF response, AM can meet HiFi criteria.

I have a set of Benny Goodman LPs, that were made from "Air Check" recordings. These were made off the air, AM radio, using good but primitive recording technology (must have been disc recordings, since mag tape was not invented yet).
These recordings have the usual LP limitations, but they are every bit as good as similar vintage LPs which were made in studios.
My mom has an old tube Sylvania table AM radio that easily picks up the clear channel stations hundreds of miles away with just the internal antenna. They do still built good AM tuners in car radios..
http://cgi.audiogon.com/cgi-bin/cl.pl?misctunr&1079913024

Perhaps the venerable Mr Scott can optimize a tuner for your needs. I enjoy FM on the one he did for me.

Course if it's Rush you may be SOL. Cheers.
They actually still do make good AM radios. If you buy a decent portable short wave radio, they include the AM band. Even the better ones at Radio Shack work well. Popular professional brands are Grundig and Sangean.
The best AM section I've found in a tuner so far was, unfortunately, in one of the most expensive tuners out there as well. I won't go into full technical detail, but suffice to say the AM section in the Sansui TU-X1 with its synchronous AM detector is simply one of the very best ever produced. Reportedly, Carver also did a decent job with the AM section in their TX-11a and TX-11b as well, although I've never used one. I've also gotten good AM out of my Sony ST-S730ES which has selectable bandwidths, although it was by no means as good as the TU-X1, with its wide/narrow, selectable filters, and synchronous detector. The Philips AH673 also had a good AM section, reportedly. Sansui and Pioneer also put decent AM sections with selectable bandwidth in a few tuners, Pioneer specifically in the TX-7800 and TX-9800. The most economical might be the Carver, where I'd take a second look for sure. The lower end Pioneers and Sansuis don't seem to have had the filters often necessary for good wideband AM reception. Hope this helps.