Airport Drives Me CRAZY! New 802.11n Network Slower Than Old 802.11g/b

Question

I've been using Macs since 1988 and consider myself an advanced user. However, every time I setup a new Airport wireless network or re-configure an existing one, I feel like a helpless newbie trying to figure out how to open a folder on my desktop. No matter how many times I read the manual or the help files or these forums, I can never grasp what seems like it should be a simple path from A to B to C.
Anyway, here's my current situation: I've been successfully (I think) running a 6 year old AP Extreme Base Station [AE] (in my home office addition) and 2 Airport Expresses [AX] (one AX roughly 15 feet from the base station--through sheetrock, and the second AX roughly 30 feet from the first AX--through sheetrock and some wooden stairs. (so roughly 45 feet from AE to 2nd AX). It wasn't the speediest thing going but it did the trick with older Macs.
I recently bought a MacBook Pro which supports 802.11n. I most often use this laptop at the point in the house furthest away from the AE (Base Station) The AE (Base Station) is in my home office connected to my MacPro desktop (see #1 below). In addition, the family iMac is also in that room furthest from the AE. Using the new MacBook Pro with the old 802.11/g/b network turned out to be painfully slow. I was experiencing the same slow network connection my family has complained about for years with their older Macs and 802.11g/b.
I decided it was time to upgrade the whole network, if only to speed up my MacBook Pro connection. Bought new 802.11n Airport Extreme (MC340LL/A) and 2 new 802.11n Airport Expresses (MB321LL/A). Setup did not go smoothly. Again, my normally competent Mac persona was reduced to a babbling three-year-old. Had three different Apple techs on the phone trying to help me through it. Got different, contradictory instructions from the last two. Finally got all three units working, only to find that not only does my MacBook Pro seem even more sluggish than when connected to the old 802.11g/b network, but my wife tells me web pages are taking at least twice as long to load as with the old network.
As concisely as I can lay this out:
*1. Airport Extreme (Base Station)*
Connected via Ethernet from its WAN port to my Comcast cable modem. One Ethernet (LAN) port on that AE is then connected via Ethernet to my Netgear 8-port Ethernet switch. Ethernet from switch to Ethernet port 1 on my MacPro. (MacPro does NOT have an Airport card because I forgot to order one. Also I confirmed that this setup was functional by connecting to the AE wirelessly with my MacBook Pro showing the name I'd given the new network prior to adding the two AX's to the mix).
Some Airport Extreme settings of note (all accessed via "Manual Setup" button):
Airport Tab > Summary
Version 7.5.1
Wireless Mode: Create a wireless network
Channel: 149 (Automatic), 1 (Automatic)
Wireless Clients: 3
Airport Tab > Base Station:
Allow Setup over WAN: Unchecked
Airport Tab > Wireless:
Allow this network to be extended: Checked
Airport Tab > Guest Network:
Nothing checked
Airport Tab > Access Control:
MAC Address Access Control: Not Enabled
Internet Tab > Internet Connection:
Connect Using: Ethernet
Ethernet WAN Port: Automatic (Default)
Connection Sharing: Share a public IP address [Think this one is probably wrong]
Internet Tab > TCP/IP:
Configure IPv4: Using DHCP
Internet Tab > DHCP:
Shows Beginning & Ending Address
Internet Tab > NAT:
Enable default host at: Unchecked and blank field
Enable NAT Port Mapping Protocol: Checked
Internet Tab > Advanced
Didn't touch anything here, so all at defaults
*2. Airport Express #1: Living Room Express (Closest to AE (Base Station)*
Airport Tab > Summary
Version 7.4.2
Wireless Mode: Extend a wireless network
Connect using: Wireless Network
Channel: 1 (Automatic)
Wireless Clients: 1
Airport Tab > Base Station:
Allow Setup over the Internet using Bonjour: Unchecked
Airport Tab > Wireless:
Wireless Mode: Extend a wireless network
Allow wireless clients: checked
Airport Tab > Access Control:
MAC Address Access Control: Not Enabled
Internet Tab > Internet Connection:
Connect using: Greyed-out, not selectable
Connection sharing: Greyed-out, not selectable
Internet Tab > TCP/IP:
Configure IPv4: Using DHCP
Shows IP Address
Internet Tab > Advanced
Didn't touch anything here, so all at defaults
*3. Airport Express #2: Dining Room Express (Furthest from AE (Base Station)*
Airport Tab > Summary
Version 7.4.2
Wireless Mode: Extend a wireless network
Connect using: Wireless Network
Channel: 1 (Automatic)
Wireless Clients: 2
Airport Tab > Base Station:
Allow Setup over the Internet using Bonjour: Unchecked
Airport Tab > Wireless:
Wireless Mode: Extend a wireless network
Allow wireless clients: checked
Airport Tab > Access Control:
MAC Address Access Control: Not Enabled
Internet Tab > Internet Connection:
Connect using: Greyed-out, not selectable
Connection sharing: Greyed-out, not selectable
Internet Tab > TCP/IP:
Configure IPv4: Using DHCP
Shows IP Address
Internet Tab > Advanced
Didn't touch anything here, so all at defaults
SETUP/GOALS:
With Airport Extreme (Base Station) as the starting point, have the two Airport Express units with the strongest, fastest signal possible, provide Internet access (and file sharing, iTunes speakers capability) to three Macs (one older iMac, one older PowerBook and my new MacBookPro). Again, I believe my new MacBook Pro is the only one with 802.11n support, so I don't expect the other Macs to take advantage of the speed boost offered by the three new 802.11n devices.
+Any and all help with this will be greatly appreciated. Thanks!+

Answer 1

{quote}With the AirPort Extreme, in the AirPort panel, Wireless tab, click on the button for "Wireless Network Options", check the box for "5 GHz Network Name", and enter a different network name. (That can be trivially different, such as the name of the main network suffixed with an underscore and the digit 5.) Once configured that way, connect your "N" gear to each network in turn to see if one is any better than the other. (If you're wondering what effect this would have, it allows segregating your "N" gear from the older gear to prevent the older gear from slowing down your network. However, distance and interference from things like walls may negate any advantage.){quote}
William: I was gone most of yesterday, but had a chance to implement your recommendations today. I added the 5 GHz network as you suggested, but in order to connect to that at all with my 802.n11 MacBokk Pro, I need to be within a few feet of the AE (base station). If I try to access that network even from the next room (well within reach of both the AE and the livingroom AX, I get one bar and "failure to connect" messages just trying to logon to that network.
However, I did some experimenting that (as of right now, anyway) resulted in much faster network access, not only from my MacBook, but also from the older iMac which is the furthest Mac from the AE. According to my wife, that iMac is "loading web pages faster than I've ever seen them!"
Here's what I did:
1. Moved all three units to places where it seemed they would have the least amount of interference with the clearest path from unit to unit, also raising the height of both AXs from about 2-3 feet from the floor to about 5-6 feet from the floor.
2. Changed one setting on the AE (base station): Wireless Tab > Wireless Network Options > Multicast Rate ---> Changed this from Low to High.
I have a feeling the location shifts made the real difference, but I will try changing the multicast rate back to "Low" just to see what happens.
Paul