6400 vs 6500

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  • Updated 8 months ago
Hello all, newbie here.  I am interested in the 6400 and have seen the specs on the Flex website.  I see that there was a previous model, the 6500, that was apparently discontinued.  I guess I am confused about why a newer model has a lower number designation, and what the difference in features are.  I have found a spec sheet on the 6500 but it is hard to compare the two models because the different spec sheets list different specs and there is no place where they are compared side-by-side.  I see where they are offering a refurbished 6500 for $1000 more than the 6400.  Is this a pretty good deal or is there something about the 6500 that makes it obsolete or soon to be obsolete?
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Bill - W7DOC

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Posted 8 months ago

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Bob Craig, K8RC

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The original lineup, bottom to top was 6300, 6500, 6700. The 6300 had a lower spec SCU (Spectral Capture Unit)  than the other two units. the 6500 had a single higher spec SCU the 6700 two SCUs.

In the new lineup 6400=upgraded 6300, 6600=upgraded 6500 and the 6700 is still king.

So the total "spectrum" of 6000-series radios, from bottom to top is:
6300,6400,6500,6600 & 6700. The M variants essentially include a Maestro console as a front panel.

There are other differences but that's the basics.
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Brian Morgan VK7RR

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When the two new models were announced I looked long and hard at whether to trade in my Flex 6500 for one of the new models. As Bob has said, the 6400 is in between the old 6300 and the 6500 and the 6600 in between the 6500 and 6700. I decided that my 6500 does everything that I needed. If I was thinking about what to buy, I would choose between the 6500, 6600 and 6700 depending on your budget. Whichever you choose, you will be very happy with it.
If I had my time over  I would still have chosen the 6500.
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WH6HI - Pat

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I had pretty much the same thoughts about trading. But what changed my mind was actually the physical height of the 6400/6600. It did not fit on my desk as I am limited in space. I know that for most it is a minor concern. And it is minor , but differences in specs are so close that it was just not worth the extra cost for me . the amount of changes to my shack that would have to happen was huge. I took that cost and built a better antenna system that is paying off immensely.

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Bill -VA3WTB

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The 6400 is a direct replacement for the 6300, both radios sport 2 slices. The 6500 has up to 4 slices. And the 6500 has very good pass band filtering, pre selectors.
They have stopped production on the 6500 but is still fully supported as all Flex radios are, parts pending. None of the radios are obsolete, they still do what they were intended to do and the 6000s all used the same software.

If you were to move from a 6500 it seems to make sense to go to the 6600 witch is a nice step up.
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NX6D Dave

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The 6300 and 6500 are no longer in production. I don't think they are in stock any longer, but I'm not certain about that.

The 6700 is still in production as it has the VHF range that the other models don't have.

All of the models are equally supported by the software and servicing, so there is no inherent risk in buying a 6500.
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Steve - K6SRS

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The 6300 and 6500 aren't in production anymore, but Flex takes them as trade ins, brings them up to the newest software and sells them with a warranty.  I just got a 6500 from them, and am totally satisfied.  I'll wait for the 6800 to go BIG.  
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Bill - W7DOC

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Thanks for the responses.  I'm thinking the refurbished 6500 is a good value for the price.  I'm not a rabid contester or DX'er so the 6700 is a bit too high end and costly for me.  Like Steve, I would wait for the next big top model to upgrade, or maybe get a refurbished 6700.  Kind of like buying cars, I haven't bought a brand new car for 30 years.  I'm still using the 756 PRO I bought in 2000, so I figure I'm due for an upgrade from that.  And I love the idea of using a graphic computer user interface.
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Gary NC3Z

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I just went through a similar thought process and ended up buying a Certified Pre-Owned 6500 last week.
Performance numbers wise I can't see that the 6400 (or even the 6600) will show anything worthwhile. The 6500 comes with an ATU so you need to add that into the price. I liked the native XLR mic connection of the 6500 too. Plus the 6500 will give you 4 RX/Slices vs 2 on the 6400.

So for me the CPO 6500 looked like a nice deal.
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Don Babcock

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Same here Gary! The only reason I am at work today is because UPS is scheduled to deliver it TODAY!
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Chris Tate - N6WM, Elmer

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To address the numbering question, I believe the 6400 is the successor of the 6300.  It has better specifications and updated hardware including the M series panel option still 2 panadapters.  the 6600 is the successor to the 6500 still 4 panadapters.  it adds a second SCU as well enhancing the value.  the 6700 remains the flagship, supports 8 panadapters, includes 2m capabilities and other ehnancements 
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I looked at all the models and the are several improvements in 6600 that were significant. Impjroved tx phase noise. This is not just a spec number but a cleaner tx. The 2 SCUs is a big thing. The 7 th order received filter is important. SO2R is not a big issue as a contest unless ur a contested but monitoring two bands with separate rx filters and low phase noise is significant to all when you get use it it. Without 2 SCUs the radio opens up to Wide and has no rx filter, wide open from broadcast band to 54 MHz. When monitoring two bands. Two antenna connectors and two rx connectors including switching from SmartSRD including local, local remote and Internet remote is a feature.

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Ken - NM9P, Elmer

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Bill is correct....The 6600 is indeed an upgraded successor to the 6500.  And it is LESS money, too!  (Unless you want the 'M' Model)  Having TWO SCU's is a big difference, as well as the 7th Order Bandpass filters on the contesting bands.  

SO2R or not, it would be nice to be able to work 160 on one antenna and 6 or 10 on another at the same time!  I can't do that on my 6500 now.  I can only use one antenna at a time.

I own a 6500 and plan to upgrade to a 6600 as soon as I can afford to.  (I actually ordered one on Thursday before Dayton/Xenia opened last year, but had to cancel it when hit with some major medical and automotive bills and other financial uncertainties.)

I think it is going to turn some major heads once it saturates the market.

Back to the original post -- I would see the 6400 as a downgrade from my 6500. I would certainly miss the ability to use 4 pans/slices instead of only 2 on the 6400. And I would miss the better bandpass filters, balanced Mic input, and wider panadapter and ultimate frequency range, too.  To me, an extra $1000 for a good 6500 would be worth it, if you can afford it.

But the 6600 would definitely be an upgrade!
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Ken - VE5KC

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I had a Flex-6500 for a couple of years until some things changed in my life. Health problems, hospital time etc. left me down and negative. Add to this Flex discontinued the 6500 meaning immediate faster devaluation.  Without fully thinking things through I sold my 6500. I figured I would get what I could out of it, while I could, before the new models were available. I figures an Icom IC-7300 would be enough for me and less complicated to operate.

Several month later, my health improved a lot and I was doing good with adapting to my new life situation/ disability. Big surprise, I started missing my Flex 6500..  I used my Flex 1500 a bit but QRP can be very difficult from my part of the world. PowerSDR has some neat features but it's not SmartSDR. I decided to buy another Flex 6000 series rig but what model. I thought that maybe I could settle for a used 6300 but really what I wanted was a rig as good as the 6500.

I asked some of the people from Flex and read some posts from testers. I was told that the 6400 would be as good as the 6500. all it would lack is the two extra slices. As to the 6300, it lacked the preformance and specs of the 6400 had. The 6400 has better specs and is not much more expensive than a referbished 6300. So I decided to buy a Flex-6400. At first I thought the  6400M would be the radio for me and order one.  After more consideration I realized the "M" was a waste of money for me. I would not use the front panel very much after playing with it the sirst while. In my shack I have two computers that can both run my Flex.. Someday both at the same time. Also, when I had the 6500 I really didn't operate from in the shack very much. That is one of the things I missed, one of the big advantages of these radios is not being tied to the ham shack. Final decision made, I canceled the order fof a 6400M and changed it to a 6400.

Now I have my 6400 and it works great. It was easy install and setup for me, having previously owned a 6500. Bottom line with the 6400, I see no difference in preformance. The only difference is in it only having 2 slices instead of the 4 that the 6500 has. I admit that once, I did find myself trying to open more than 2 slices. It wasn't important or something I would normally want to do.

The bottom line, as I see it from my experiance, get a 6400 instead of a used 6300 or 6500. Get the 6400 instead of the 6400M unless you plan on spending a lot of time setting infront of your radio. Enjoy your new rig and the ability of not being tied to the ham shack.

Ok, so much for my story.. Hi..