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6500 not as good as FTDX3000?

I just purchased a 6500 and have been comparing it to my FTDX 3000 and to a SDRPlus SDR.  I am trying my best to like the 6500.  I love SDR but in a 3 way simultaneous operation I cannot get the 6500 to work as good as the Yaseu FTDX3000.  Maybe I am doing something wrong?

I am running the latest software.  All 3 units are tied to the same receive antenna via a powered HF splitter.  When using the FTDX3000 with its NR set to 4 the background noise falls to a comfortable level that makes listening to long rag chews very nice.  It is even better using the NR on a SDRPlay SDR.  Using the NR on the 6500 I cannot find a setting to get as clean or as much noise reduction without distorting the audio.  Also  when listening to  very weak signals the FTDX3000 with NR makes the station readable where nothing I tried on the 6500 would pull the station out.  This is very frustrating since I expected much more.

I researched all the reviews and played with the the FLEX at all of the hamfests.  I finally made the decision to purchase, but it has not been a great experience.

Am I doing something wrong?  Can anyone suggest any settings to try?  I do not want to return the unit since I do love SDR.


Demos KR4US



  • Ria
    Ria Member ✭✭
    edited November 2019
    The NR is a known weak point of the flex rig/software, or rather, it is a work in progresss. That doesn't mean overall one is better than the other. However if NR is make or break for you then the one with the better NR would win, but overall there are many criteria that people use to choose a rig.
  • Jd Dupuy
    Jd Dupuy Member ✭✭
    edited February 2017
    I never use NR to pull out a weak signal. I run the RF Gain up to quiet the background noise and increase the volume as needed. It's referred to as "Signal to Noise Ratio". Something I learned to perfection operating weak signal 144 thur 10 Ghz. Good luck!
  • Demos Doulou
    Demos Doulou Member
    edited March 2017
    Not just the NR, especially if it is still a work in progress, but the situation were the 6500 was not hearing as well as the FTDX3000.  That is the main issue.

  • Jim Gilliam
    Jim Gilliam Member ✭✭
    edited February 2017

    The noise reduction on the 1500, 3000, 5000 is nothing to write home about either. Also, that of the 6500 is about the same in my experience. I think the other rigs use chips dedicated to noise reduction. Perhaps it is much more difficult to write firmware to compete with these chips.

    Jim, K6QE

    Jim, K6QE

  • Al_NN4ZZ
    Al_NN4ZZ Loganville GAMember ✭✭✭
    edited March 2017
    Hi Demos,
    Here are 3 ideas that address the issue including the other good suggestions above.

    Noise Reduction:

    Peaking gain:

    Automate the AGC-T setting

    Check them out and add your votes and comments if you agree.

    Regards, Al / NN4ZZ  
    al (at) nn4zz (dot) com
    SSDR / DAX / CAT/ 6700 -  V 1.10.8

  • Demos Doulou
    Demos Doulou Member
    edited February 2017
    The best one I have found is implemented in SDR Console using the
    Ephraim-Malah Noise Suppressor algorithm.  I use this on the SDR Play SDR.  This is implemented in software on the computer so it is possible.

  • Demos Doulou
    Demos Doulou Member
    edited February 2017
    Thanks. I will try these tonight
  • Kevin
    Kevin Member
    edited July 2019
    I have only done side-by-side comparisons with my KX3 which I think has a great receiver in it. I think JD's technique above using RF Gain makes a huge difference. I discovered this during the weekly fox hunts where I could hear the hounds but the fox is buried in the noise.

    I'll do all the normal stuff with AGC-T and a bit of NR and some APF (100 Hz and above only). Then I'll bring up the RF Gain to +10 or more even on 40 or 80 meters (where the winter hunts occur). ****... the fox pops out of  his hole. It is generally the last thing I try but it often makes the most difference.

    Because we are using our ears to do the comparison and not test equipment I would expect your results to be mostly even across the three receivers. I think the differences in most good receivers today are a bit beyond what our (my) hearing can discriminate. If the Flex is not performing as well in your ears and something isn't broken (antenna port, coax, front end, whatever) then I suspect adjusting some of the receiver's parameters will make the difference. Being able to test all three receivers side-by-side gives you the opportunity to really get an understanding of the adjustments.

    For me, NR's weakness is not its inability to reduce noise. It seems to do a fine job of that. Where I have the problem is the distortion it adds to CW making it rather unpleasant to listen to. Reduce NR to a point where there's no distortion and NR pretty much isn't doing anything. Try that RF gain.

    Kev K4VD
  • Bob Kozlarek
    Bob Kozlarek Member
    edited February 2017
    So it sounds like your comparison is mainly on the NR feature. Like ice cream, "noise" comes in many flavors. I had a noisy pole transformer several blocks away that the 6500's noise reduction virtually eliminated it, until I tracjked it down and had it replaced. I also had a dimmer in my home for which it did absolutely nothing. Comparisons with SDRuno on my SDRplay also showed that different radios respond to different noise quite differently. The only consistency, was inconsistency. The only definitely statement I can say is that it was better (more diverse) on my Flex 5000, but by no means is it "ineffective".
  • Gary
    Gary Member
    edited April 2017

    hmmm.... I've had a 6700 and have been A/B testing it for months against the 3000's bigger brother the 5000.... and to date I've not found a single case where the 5000  received better than the 6700 - AND the inverse as well - where the 6700 received better than the 5000. I can manage in all cases to adjust them to match the ease of listening and weak signal capability of both radios. So I wonder if you're not doing something with the 6500.

    One thing I find frustrating is that the NR and APF levels seem to always reset to 0. I am constantly having to go in and change them (this is using the Maestro). Likewise the TX and RX EQ's. Oh and the TX Delay for the relay out - always resets to 0. No matter how many times I've hit "SAVE" on the Global, TX, MIC profiles these NEVER get saved. My point is is it possible you haven't adjusted the level of the NR and/or NB? (and APF also does this if I remember correctly - resets to 0)



  • W0JD
    W0JD Member ✭✭
    edited January 2020

    I own both and overall find the Flex superior for my uses and operating style. I did however need to adjust my operating procedures when switching between radios. I was reminded of this a few weekends ago when I operated at a field event using a FT-450D.

    When faced with a weak signal on the Yaesu or any mixer radio I crank down the passband or width depending on the features available. And often times need a bit of IF shift and audio conture to enhance the voice frequencies. The main problem with the 3k is the big gap between the 3khz roofing filter and the 500hz CW filter. Below 3k DSP is employed to narrow the passband which is a compromise.

    As the Flex has an infinitely adjustable passband which is in the RF side of the RX not the audio chain like a mixer RX. I crank down the passband, adjust the AGC-T if needed and the RX audio EQ if needed. 

    While I can get to a similar result with either radio, IMHO the Flex edges out the 3k while presenting an easier to use interface than a knob radio.  

    I guess my message is this, try narrowing the bandwidth run a small amount of NR. Mine is normally set at less than 10 and also have your AGC-T setup properly. I normally run in the 35-40 range.

    I almost forgot this, try the Binaural audio setting on the RX tab in the radio setup dialog. I use a set of powered computer speakers and I find the effect quite beneficial with speakers or headphone use. 

    73, Jay N0IAI

  • WX7Y
    WX7Y Member ✭✭✭
    edited June 2020
    Just a couple thoughts
    I also use the receive Equalizer to cut out any white noise and low rumbles that my Ears don't like and bring up what they like to hear because this is usually just garbage anyway, along with the AGC-T I very rarely use any NR.

    If your using the S meter to say one radio receives better then the other remember the FLEX S meter doesn't change when a Pre-amp or Attenuater is used and MOST other radio's the S Meter change levels so you aren't really getting a true comparison because it is not calibrated. 

    Signal to noise is by far much more important comparison from one radio to another and most Amateurs don't have the equipment to check this so we have to rely on our our ears and we all hear things differently. 

  • Michael Aust
    Michael Aust Member ✭✭
    edited February 2017
    I also suggest trying the Rx EQ, it makes a big difference for us old-timers with high end hearing loss !!
  • Bill W2PKY
    Bill W2PKY Member ✭✭
    edited February 2017
    Yes, dropping out the bass 3-500 Hz and below can help a lot.
  • Gary L. Robinson
    Gary L. Robinson Member ✭✭
    edited February 2017
    I will attest to that also!
  • Terry K7NY
    Terry K7NY Member ✭✭
    edited January 2020
    My buddy sold his FTDX-3000 and bought a 6300 and never looked back.
    Terry K7NY
  • Bill -VA3WTB
    Bill -VA3WTB Member ✭✭✭
    edited February 2018
    The one big thing the Flex has is that wonder called the AGC-T that no other radio has. You need to set the AGC-T at it's sweet spot. This is not a setting you set and forget it, you may need to change it slightly if conditions change, or changing bands. Once you have it set, it will make things very quiet and all the signals will be heard. Remember, every time you adjust the AGC-T wait a minute for it to calebrate. Keep moving it slowly and wait for it to kick in, then move again till you find the knee.
  • Mike KD2CJJ
    Mike KD2CJJ Mr Member ✭✭
    edited February 2017
    I had a FTDX 3000 for a few years.. Purchased it the moment it came out.  I loved the unit.. I could not afford to keep both and was very attracted to the possibilities of the Flex thus picked up a 6300 and sold my FTDX (to my dad).  

    There is no comparison to noise OR noise blanking... the FTDX is hands down superior..  I had them side by side for a while and noise that could not be blanked out by the Flex was gone with the FTDX... 

    In general the FTDX has a more pleasant sound/audio out of the box.  However the Flex is far superior is every other way.  It just takes time to adjust the AGC, volume, etc. etc.  

    Once you tweak the settings enough it starts to surpass the audio of the FTDX.  Couple that with all the functional capabilities you start to see the light.  I almost dumped the Flex because of this frustration but once i gave it time I learned to love it.  You will learn to love it once you have figured out the right combination of settings.

    I would suggest to flex however to have pre-sets or suggested starting parameters that tune the radio right out of the box - even to the demise of performance.  Its discouraging when you turn it on and it seems no where near your ancient radios performance.
  • Al_NN4ZZ
    Al_NN4ZZ Loganville GAMember ✭✭✭
    edited March 2017
    Hi Bill,
    IMHO, For many (maybe most or possibly even all) of the use cases it could be a "set it and forget it" option with the automation feature.   

    Automate the AGC-T setting

    And since you could still manually tweak it, you could figure out when you feel the automated feature is not perfect and still do it manually.   Currently it is easy to forget to constantly adjust the AGC-T with every band change, antenna change, condition change, or even which direction your gain antenna is pointed.  

    Regards, Al / NN4ZZ  
    al (at) nn4zz (dot) com
    SSDR / DAX / CAT/ 6700 -  V 1.10.8

  • k0eoo
    k0eoo Member ✭✭
    edited February 2017
    Hello Demos,  I hear you are using a powered antenna splitter.  Such units buffer the input to the radios and can introduce their own noise figure and reduce the dynamic range of the flex; which is much higher than the other radios in your test.  Try just switching the one antenna between each receiver and eliminate the active splitter.
  • Manfred HB9FLU
    Manfred HB9FLU Member ✭✭
    edited March 2017
    I own an 6300 with Maestro and a brand new FT DX 3000. Both radios have very good receivers, but when going on crowded bands, the filters of the flex are superior. I normally doesn't use the NR on both radios. For reducing noise I have a BHI noise reducting tool. Reducing noise with the Flex is best done with the AGC-T. 73 de Manfred HB9FLU
  • Demos Doulou
    Demos Doulou Member
    edited March 2017
    Thanks everyone for the comments and tips.  After spending many hours adjusting settings and doing comparisons, I decide that at this time the Flex is not for me.  I will take another look at the platform at next years Orlando Hamcation.

  • Andrew Thall
    Andrew Thall Member ✭✭
    edited March 2017
    I had a FTdx3000.  My operation is strictly cw and digital.  The flex 6300 could decode digital signals that the FTdx3000 couldn't even hear.  I understand that the AGC-T takes some time to get used to.  Having said that, I would never consider going back to an analog radio.  I am anticipating that when SSDR 2.0 comes out (hopefully at Dayton), that operation of the Flex series will be even better.
    Andy, k2oo
  • YV5WZ
    YV5WZ Member
    edited March 2017
    Which BHI noise reducting tool do you have?
  • Manfred HB9FLU
    Manfred HB9FLU Member ✭✭
    edited March 2017
    I have the desktop speaker and a module inside of my FT-817. The speaker sounds very good and noise cancellation is very effective.
  • Johan SE3X
    Johan SE3X Member ✭✭

    Old thread but interesting while I had to send my 6700 (bought early 2018) to service and found an almost unused FT DX 3000 for back-up a month ago.

    I do a little bit of everything and I do believe my 6700 overall is the best I have had and could ask for. But I'm impressed by the 3000 as well. Very nice Rx and I agree with previous posts about very good NR and very pleasant radio to listen to long Ragchew Q's. What I'm not impressed with is the hopeless use of CAT software to integrate different programs with the radio. Nothing beats, or even come close, to Flex CAT! Add DAX to that and nothing compares in simplicity and ease of integration.

    So far I see pros and cons for both radios and can't claim a winner. Don't think I will either and my conclusion are they will be used for different things. I will sure keep my 6700 and will keep the 3000 as well. Looking forward to have them side by side and continue comparing and learning their strengths and weaknesses.

  • Patrick
    Patrick WH6HI KauaiMember ✭✭✭

    I agree that noise mitigation is a problem. My own solution was to add a bhi DSP to the setup. This made noise pretty much go away. This makes my 6700 absolute pleasure to use, even with weak SSB signals. So sensitivity is not the problem, but noise mitigation solutions are with Flex radios. FlexRadio needs to pay attention to this. Contesting may be important to part of the Flex owner population, but noise mitigation, is a situation that has to be important to all owners. Even the contest oriented operator. They noise mitigation also! The dependence of out side suppliers for solutions is not a good policy. It adds more complexity via hardware/software solutions then should be needed.

  • Wayne VK4ACN
    Wayne VK4ACN Member ✭✭

    Patrick, Is it the new EQ20 dsp, and what speaker do you have connected to the output of that.

  • KF4HR
    KF4HR Member ✭✭

    Demos I moved from an ICOM IC-7800 to a Flex-6700 about 4 years ago. I found I was up against a learning curve on my Flex. It took awhile to get the nack of properly adjusting the AGC-T, NR slider, and the preamp setting to maximize the readability, but once i did I found my Flex worked just as well (if not better) than my ICOM. By the way, I've found that setting the AGC to SLOW when copying SSB eliminates AGC "pumping."

    My suggestion is to hang in there with your 6500. It does take some time to get the hang of it, but with a bit of practice you should be able to equal the readability of your other radio.

    That said, the Flex NR features do need improvement. This is one of the major complaints Flex users have. Unfortunately, for the last year or so, new software features SmartSDR and/or software updates have slowed way down (snails pace), but Flex users continue to hold out hope for improvements. After all, software is what makes or breaks a SDR rig.


  • @Kf4HR With your comment that Flex Radio has slowed down to a snail's pace with software development, then where are their resources going? I have read many complaints about the NR needing improvement. If the complaints are so wide-spread, then I would expect that Flex would work to improve that portion of the software and push out a patch to improve that portion of the software.

    It would be interesting to understand how feature improvements and and bug fixes get prioritized. Back in the days of PowerSDR, the improvements were much faster and significant.

    Back in the days of PowerSDR, there was not a lot of competition in the SDR world, but today is a different story. Business logic would usually dictate that improvements would come out faster to help differentiate the product from other players in the market place, but that is not the case. Of course, there is something to be said about a stable code base also.

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