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Low audio and to much bass




 
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WB4AIO
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« Reply #25 on: August 04, 2020, 12:40:48 AM »

[...]
I wanted to post an ESSB recording I heard a few years back but can't find it in my docs.  I think it was by a VE7 or W9 or maybe another ESSB enthusiast.  The audio was magnificent for a 4KHz bandwidth. Except for a few artifacts, it sounded just like AM.  Do you remember seeing it or maybe have a copy? I posted it in one of the threads on this BB too.

Right now I'm busy mounting parts on my new single 3-500Z amplifier. Baby Blue panel with viewing window. Once the metalwork is done, it's like building a Heathkit. Watch for some pics soon.

T



Good luck with the new rig!

My favorite eSSB group is the 3630 gang. 7.5+ kHz audio all the way, baby.

Here's a sample:

http://liberty.3950.net/N9VR%20NU9N%20et%20al%20on%20influence%20of%20eSSB%203630%20kHz%202019-1202_081912_B1.mp3

73,

Kevin, WB4AIO.
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« Reply #26 on: August 04, 2020, 11:35:10 AM »

Tom

I heard you on the air a while back and your voice sounds just fine for radio, maybe not a big broadcaster voice but better than average. As for me, I have decent voice for radio too, some what like you except I sound young. I turned 60 a month ago and I been told by many people I sound like I'm in my early 40's or younger and are quite surprised at my real age.

Oh yes the Aphex 104 ... Can't stand that thing, nothing like artificial bass to ruin things. It was all the rage around 2000 and many of my friends had them. Drove me nuts with that sound. I use to resort to taking my IF shift or DSP high cut and remove that annoying bass from my receiver. Lucky it seem to be a passing fad and I don't hear much of them anymore.

Yep 4 khz ESSB sounds unreal, the clarity and definition is off the charts. It's really that good when done up right. When I was experimenting with 6 khz  SSB I found that 4 khz was the best overall bandwidth. Just enough for the sound we were looking for  (and wide enough to make the transmitter transparent) and not to much to bother other hams on the band. Also it was easy to listen to on RX with noisy bands.

I'm not sure if you ever listen to 80 hz to 6.1 kHz of flat RX SSB but its very harsh on noisy band like 75 meters. It's really bright and sounds unnatural when listening to band noise with good speakers or headphones. I could only take a little while of it before being fatigued and always grabbing the RF gain control ( wide AM is kind of the same ) But 4 khz on the other hand is perfect. Band noise sounds natural and it's easy to listen to.

I have a Kenwood TS-930 that is moded up with 4 khz Inrad filter in the high IF and 4 khz Collins filter in the 455 IF all audio circuits set up to match the filters and it sounds unreal on receive and transmit at 80 hz to 4.1 khz

Is your 1000D stock ??  have you change the filters out to wider Inrads ??

I have seen pictures of your builds and very very impressive, I wish I had that motivation and enthusiasm. I like to restore the old classic Nipponese boatancher like the Kenwood 940 and 930. I make a few things here and there, but thats about it. I'm really thinking about building a LD Mosfet amp in the future, I want to get totally away from tubes in linears. My big thing is modifying new & old radios and repairing, coming up with all kinds of crazy modifications.

I understand the AM comradery and that's cool. I like AM & SSB and enjoy both. I think the love for AM comes from my CB days. But I have to say there is quite of bit of dislike for ESSB & SSB on this forum ( under the surface ) and on the bands.The term slopbucket and others terms say it all, doesn't bother me ....  but diehard AMers & boatancher enthusiasts seem to be polarized on one mind set of thinking.

J


Nothing wrong with the  Aphex 104.  I currently use an Aphex 204.  I also use a Behringer  EX-3200.  BUT they have to be tweaked very very carefully.  I use a behringer MIC-2200 mic pre-amp with my  RE-27....and it has one parametric EQ  built into each channel. I use the eq to do a cut at aprx  160 hz..and  1.7 octaves wide.  Then it all sounds good.  I also tried doing the same cut at  160 hz in my main EQ..and can't get the same effect...and I still don't know why.

Both my FT-1000-MP-MK-V's are modified with 6 khz filters..and that combo is good up to aprx 5.7 khz wide.  (ESSB mode).  Even on a noisy 75m band,  I don't find the 5.7 khz fatiguing on  RX.   I also use aprx  4 or  4.5 khz  BW.  That too works good.

Since I have 2  x channels on all the rack gear, I typ use the left channels on  TX..and have experimented with some of the right channels on RX.   By adding artificial harmonics on RX, and also eq'ing the 'new harmonics', I found that  super weak  KH6's, just above the noise on the upper bands  improved a bunch for intelligibility.  A  real eye opener.  No luck with the ..'all mode squelch' on  ESSB, so tried  several
experiments using the  downward expander on  RX.  That was used in conjunction with backing the RF gain way down, pre-amp off, and 6db attenuation dialed in.    Everybody stops talking..and the band noise just fades away.  Again, it took many tries to get this right.

I could never get the RF compressor in the MK-V to ever work right, until I shifted the Cxr  osc over by  40 hz, then bingo,  I managed to nail it. With most of the essb  folks on the west coast being loud to begin with, those that are a bit bass heavy is no big deal.  Under marginal conditions, you have to switch to plan B.

The amount of hrs I have spent tweaking  stuff is unreal.   After all is said and done..it works for me only.  I used to heat this all the time, whereby another ham would drop by..and get on the   mic..and it's good, but overly  brilliant.  Plan C  was  stored eq pre-sets for when other folks came over to operate.

What would be a big help on  RX, is..'hang agc'... like  80-90 msecs.  I have not figured out how to implement it... yet.   I'm still  bumbling about on how to get the audio to sound right on AM.   I also have 2 x  FT-1000D's...and only one is modified..for  essb.   I also tried some very brief tests with FM on 10m, but did  not pursue it further.

Right now, I'm modifying the cooling in all  4 x of my  drake L4B amplifiers, adding Eimac style tapered chimneys..and also  EBM-papst blowers, and power supply mods.    The best I can come up with is aprx  300w  CXR /1200 pep  for AM mode..on  75m.

I'm also in the middle of  building another  B+  supply for my HB  3CX-3000A7 amp.  We  are allowed a full  750 watts of AM cxr..here in Canada  ( measured at the feedpoint of the ant, after feedline loss)   so to do  AM right, factoring in  feedline losses,  I need a  tube that does  800+  cxr..and 3.2 kw +  pep...and more pep, if positive modulation is more the typ  125+  %.

Too many projects these days, not enough time.

Jim   VE7RF
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« Reply #27 on: August 04, 2020, 11:12:18 PM »

You're going to need a pretty wide filter on AM Jim.

Many have taken the filter out on am, just a cap from input to output.

That necessitates outboard rack gear or other spectrum management to keep the TX bandwidth under control.

Your 7.5khz filter is gonna pass 3.75khz of AM.  I have 12 kHz in my ts850.  The ts440 switches the filter out in TX.  I have to run it with the virtual rack on a pc using various vst plug-ins.

--Shane
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« Reply #28 on: August 05, 2020, 01:10:42 AM »

You're going to need a pretty wide filter on AM Jim.

Many have taken the filter out on am, just a cap from input to output.

That necessitates outboard rack gear or other spectrum management to keep the TX bandwidth under control.

Your 7.5khz filter is gonna pass 3.75khz of AM.  I have 12 kHz in my ts850.  The ts440 switches the filter out in TX.  I have to run it with the virtual rack on a pc using various vst plug-ins.

--Shane
KD6VXI

##  Nope, the  oem Murata  filter is used on  AM..and is  6 khz wide (3.0 khz each sideband).    It can be replaced with the 9 khz murata
(  +/- 4.5 khz).... or the even wider  12 khz murata ( +/-   6 khz).   BUT, the murata is also used on  SSB  rx, resulting in agc being affected by off freq stations. (A 9 khz murata is used for FM)   There is a few other options too.  On my  FT-1000D, I used a .01 uf cap on a inrad ilter board in the 455 slot..then a 2.8 inrad in the higher IF.  That's the easy way to get max TX bw on a  2.8 filter.  Problem with the  FT-1000 D is.... you can only swing the cxr osc a  little bit ( non issue on  AM).   The MK-V has synchronous AM rx, which works good.

Since I have  2 of each radio,  one of em could be modified for AM.  This is yet one more project.

Jim   VE7RF
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« Reply #29 on: August 06, 2020, 08:44:51 AM »

How is that a nope?  If you want wide am, even you said you need to replace or bypass the filter....

I've also used my vnwa to sweep the filters.  You can can use a small pot on the ground side of the filter to elevate it from ground, and that will extend the bandwidth of the filter.

Problem was, it would have a peak where the original bandpass area was.  No free lunch.

The ts850 also runs both the 455 and the high if filters.  With a simple menu change I can choose to take one of the filters OUT.  But then on ssb if I want to go wide, I have to use the dsp100 to generate the ssb or I end up with dsb.  That really pisses people off.

The dsp100 also makes pretty good am.  But it's restricted compared to feeding the bm with a large np cap.



'-Shane
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« Reply #30 on: August 06, 2020, 09:22:47 AM »

How is that a nope?  If you want wide am, even you said you need to replace or bypass the filter....

I've also used my vnwa to sweep the filters.  You can can use a small pot on the ground side of the filter to elevate it from ground, and that will extend the bandwidth of the filter.

Problem was, it would have a peak where the original bandpass area was.  No free lunch.

The ts850 also runs both the 455 and the high if filters.  With a simple menu change I can choose to take one of the filters OUT.  But then on ssb if I want to go wide, I have to use the dsp100 to generate the ssb or I end up with dsb.  That really pisses people off.

The dsp100 also makes pretty good am.  But it's restricted compared to feeding the bm with a large np cap.



'-Shane
KD6VXI

##  You are correct. The oem 6 khz murata filter used for AM has to be replaced with either the 9 khz murata...or the 12 khz murata... or oem bypassed.      IF  I remember correctly, we are only allowed 6 khz wide, ( -26 db )  for  ssb  and also I believe  AM....(  Cdn regs)   That's only  +/- 3 khz on AM...which is semi useless.    Back in the 70's,  I owned a DX-100  and also a Johnson ranger...and can't remember how wide they are..on  AM, or how the top end was restricted.   Having said all  of that, I would not lose sleep  over having a 12 khz wide signal on  AM.   Regs  also state...'no more than  100% modulation' ( AM).... so I will interpret that as to mean  no more than  100%  Negative  modulation..and no limit on  positive modulation.   Most male voices are  asymetrical anyway.

Jim  VE7RF
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« Reply #31 on: August 06, 2020, 09:47:00 AM »



##  You are correct. The oem 6 khz murata filter used for AM has to be replaced with either the 9 khz murata...or the 12 khz murata... or oem bypassed.      IF  I remember correctly, we are only allowed 6 khz wide, ( -26 db )  for  ssb  and also I believe  AM....(  Cdn regs)   That's only  +/- 3 khz on AM...which is semi useless.    Back in the 70's,  I owned a DX-100  and also a Johnson ranger...and can't remember how wide they are..on  AM, or how the top end was restricted.   Having said all  of that, I would not lose sleep  over having a 12 khz wide signal on  AM.   Regs  also state...'no more than  100% modulation' ( AM).... so I will interpret that as to mean  no more than  100%  Negative  modulation..and no limit on  positive modulation.   Most male voices are  asymetrical anyway.

Jim  VE7RF



Canada's 6 kHz total bandwidth is a ridiculous restriction without even a faintly reasonable basis. And the 3 kHz audio "standard" it's based on, that has been drummed into people's heads to the point that some people think it's a rule, is even more ridiculous.

Voice audio narrower than about 7 kHz is less intelligible, not more intelligible.

7.5 kHz pre-emphasized audio, with a 500 Hz guard band, would be close to optimal for HF communications.

The ARRL and Collins, etc., made a huge mistake when they decided to impose the 3 kHz lie on our hobby. It was based on the idea of "how many people can we shoehorn into the band with hurting intelligibility too much" and then sold to the suckers as "increasing intelligibility."


73,

Kevin, WB4AIO.
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« Reply #32 on: August 06, 2020, 11:49:38 AM »



##  You are correct. The oem 6 khz murata filter used for AM has to be replaced with either the 9 khz murata...or the 12 khz murata... or oem bypassed.      IF  I remember correctly, we are only allowed 6 khz wide, ( -26 db )  for  ssb  and also I believe  AM....(  Cdn regs)   That's only  +/- 3 khz on AM...which is semi useless.    Back in the 70's,  I owned a DX-100  and also a Johnson ranger...and can't remember how wide they are..on  AM, or how the top end was restricted.   Having said all  of that, I would not lose sleep  over having a 12 khz wide signal on  AM.   Regs  also state...'no more than  100% modulation' ( AM).... so I will interpret that as to mean  no more than  100%  Negative  modulation..and no limit on  positive modulation.   Most male voices are  asymetrical anyway.

Jim  VE7RF



Canada's 6 kHz total bandwidth is a ridiculous restriction without even a faintly reasonable basis. And the 3 kHz audio "standard" it's based on, that has been drummed into people's heads to the point that some people think it's a rule, is even more ridiculous.

Voice audio narrower than about 7 kHz is less intelligible, not more intelligible.

7.5 kHz pre-emphasized audio, with a 500 Hz guard band, would be close to optimal for HF communications.

The ARRL and Collins, etc., made a huge mistake when they decided to impose the 3 kHz lie on our hobby. It was based on the idea of "how many people can we shoehorn into the band with hurting intelligibility too much" and then sold to the suckers as "increasing intelligibility."


73,

Kevin, WB4AIO.

##  agreed. I point out to the 2.1 khz ssb  folks that I have NOT used  phonetics  since  2001.  Even with marginal signals barely above the static crashes on a noisy summertime  75m  band.   With  BW limited  to say 3 khz  at  the top end, the  consonants all get..'crushed'.   I have a recording where a buddy slowly increased  his  top end, in 100 hz increments, from  2700 hz... up to a max of  3900 hz... and it's quite the  eye  opener.   Increasing the TX  BW...it would go from  Q3  to Q5  every time. Plan B would require a huge increase in  PO..which won't work if maxed out already.  Back in the day, Both heath and collins used a 2.1 khz filter. Heath filters  were typ 6 pole, and lousy skirts.  Audio was lousy..and the  vfo's all drifted.

##  what's  equally silly is  folks in the usa  having a 375 watt  cxr limit on AM.   Back in the day (1968-1972, when I was a swl'er)  I would hear  folks in wash state  running  800 watts  cxr and  125%  positive modulation on  75m  quite often.  That was a treat. Dead quiet..and...'full quieting'  lol.   These days, with pre-distortion,  IMD is a thing of the past.  Total BW is the same as the TX BW.

##  ARRL is dead  against the  ESSB  wideband folks.... and barely recognizes the AM folks.  The  ARRL could publish volumes on  ESSB and  AM  techniques....or at least another complete  chapter or two in the arrl hand book.   But the arrl ( and also cq mag)  will promote endless  contests..with 10,000 brain dead contesters  trashing the  phone bands almost every 2nd weekend.  Some, not  all, suffer from...
'all  knobs to the  right syndrome'. 

Later   Jim VE7RF
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« Reply #33 on: August 06, 2020, 05:23:53 PM »

We don't have a limit on carrier in the USA.  We have a limit on PEP.

I have designed a positive peak stretcher that will allow up to 400 pct positive peaks, without ever baselining on the negative peaks.

https://youtu.be/cajJYlqSv6Q

Looks amazing on an oscope and on the peak reading meter.  However, you need an SDR or sync detector if I'm over about 130 pct to prevent losing intelligibility.

BUT, I can go to about 80 watts to 1500 watts PEP, without ever hitting the negative limit.

--Shane

Edited to include youtube link

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« Reply #34 on: August 07, 2020, 06:41:45 PM »

We don't have a limit on carrier in the USA.  We have a limit on PEP.

I have designed a positive peak stretcher that will allow up to 400 pct positive peaks, without ever baselining on the negative peaks.

https://youtu.be/cajJYlqSv6Q

Looks amazing on an oscope and on the peak reading meter.  However, you need an SDR or sync detector if I'm over about 130 pct to prevent losing intelligibility.

BUT, I can go to about 80 watts to 1500 watts PEP, without ever hitting the negative limit.

--Shane

Edited to include youtube link



##  Crazy.  You are pep limited..and  we are  cxr limited. lol.   Well that's ok.  750w  cxr  and  150% modulation is aprx  4500 w pep out..and that's  measured at the  feed point of the ant.  So  add another  10-20%.  Now bias the entire mess for..class A.... and presto, we need a BIG tube.
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« Reply #35 on: August 07, 2020, 09:43:47 PM »

One of the guys on this board did a class a chain.  Tom, K1JJ.  Wanted to drop imd like a rock.

Then predistortion came out and popular a few months later lol.

My pos peak stretcher would be ideal with your limits.  It's designed for DC coupling to a solid state modulator.  I use it do drive a pwm, I designed the entire mess together, but it can be broken out.  I've also used it successfully to drive the balanced modulator in the ts440....

--Shane
KD6VXI
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