* the "low" [EQ1], "mid" [EQ2] and "high" [EQ3] EQ ranges should be set at shown. If so, you can be assured that the Tx BW is flat from 50hz to 4Khz as shown in the white noise Tx sweep chart below.

** the PE1, PE2 and PE3 ranges are used with the "PROC" = ON and set to 9 - 10 oclock. For details, please see the table "Proper Use of the SSB Speech Processor" down the page.

This section shows the FT2000 no-EQ response in either Rx or Tx modes!. This discovery has made it quite easy to 'flatten' the radio's response from 50hz to 4Khz with just one (1) EQ curve resident in the DEQ2496 and DDP. Using WWV @ 10Mhz, the following chart was made using SpectraPlus. It's the raw response from the FT2000 in 'ttbf' mode.

The overall Rx BW measures from 40Hz to 4KHz. Note that w/ the latest FW updates, the Rx response is much smoother and the upper cutoff is now 4Khz. The droop, starting at 1Khz is apx -8dB and is identical to the response in Tx mode. Since the same DSP shapes and controls the Tx as well as the Rx BW, it's logical that it would exhibit a similar response in either mode.

The overall response is shown in the blue chart; note the rolloff starting at 3Khz and attaining -8dB @ 4Khz. It's typical for the way ALL Yaesu radios are built. Note that the SECOND blue chart was recorded from the radio's PHONE jack. It shouldn't be used unless the rolloff (-18.5dB @ 4Khz) can be corrected. Check the section "How to Compensate SpectraPlus Pro for BW Rolloff" below for the method to do this.

On the hardware side, this may be possible to 'fix' by replacing a 'capacitor'. This was done during the FT1000 re-design effort. Hopefully, the same thing may happen as I start to dig into the FT2000 schematics. Until that is accomplished, the PHONES jack output is not very useful b/c of the extreme frequency response rolloff.

The green chart shows first corrected response in the DEQ2496. Note that it's essentially flat and all recordings sent to either the computer or MiniDisc (MD) are recorded with a flat response. Note that when it's re-transmitted additional EQ is needed to compensate for the Tx BW rolloff. Once done, the re-transmitted "copy" of the original signal will be identical to the way it was received. Can't ask for anything better! The "block-diagram" interconnection sketch shows the details of how-to-do-this. For Rx, this is accomplished by use of the DEQ2496.

The red chart shows the extremely flat response generated by the DDP during "playback". It's as flat as flat can be! A ESSB signal playback is indistinguishable from the original. For Tx, this is accomplished by use of the DDP.

The main settings for Rx and Tx BW measurements are: IPO = ON, RFLT = 15Khz; VRF = OFF; Width = Max. Receiving and/ or recording ESSB signals s/b use these settings. This will guarantee the maximum response from the radio.

FT2000 Playback EQ Sweep Tests - "Flat Response"
Most ESSB enthusiaists have the capability to capture Tx audio, display its BW using SpectraPlus (or similiar) and finally, play it back to you as a faithful reproduction of what was captured. This latter function requires that your radio's playback capability be compensated to be 'flat'.

Not all radios have the same playback BW; the FT2000 captures the signal from 50hz to 4Khz and can playback from 50hz to 4Khz. That's where the brick wall formed by the DSP third stage "IF" sets in . However, even with that minor limitation, the EQ must be adjusted to be flat.

To that end, the chart shows the FT2000 playback response after using the dbx DDP's channe1 for the (see block diagram) EQ.
The DEQ2496 has 31 and the DDP has 3 stages of parametric EQ that can be employed. The values for the center frequency, bandwidth (BW) or "Q" plus the level (in dB) are shown that flatten the FT2000's playback response.

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FT2000 TX EQ - Update: 5/29/17
Properly EQing for a 4Khz Tx BW is different than for a 3Khz BW. One realization is that b/c of the higher upper frequency repsonse, the low-frequency response must be increased to 'balance' the sound. It's ok to have a slight favoring of the hi-freqs since it will make the sound brighter which is always a good thing.

This section shows the EQ for the FT200's "TTBF" mode. This represents 50hz to 4Khz Tx BW. After all this time, I decided to see if the EQ has changed over the years. The MIC2200 preamp died and was replaced so time to check the settings and improve the present ESSB Tx audio.

The EQ has been modified and simplified; narrow boost @ 80hz, deep cut @ 151hz and shelving filter @ 2550hz to 4Khz. The two spike filters (452hz and 951hz) attenuate the blower noise from the linear that is apx 2ft away from the mic.

The three (3) sweeps show the details: The AQUA colored trace is the reference showing the flatness from 50hz to 4Khz. Using that as the starting point, the BLUE colored sweep shows the MIC2200 preamp response to the settings. The RED colored trace shows the total response using the MIC2200, DEQ2496 and dBx DDP processors.

FT2000 TX Freq Sweep - Update: 6/6/17
It's instructive to perform a Freq Sweep [FS] employing sinewave generated from the Utilities Menu in SpectraPlus Pro. To than end, I constructed a 50hz to 5000hz sinewave sweep with the sweep duration of 30secs. This was recorded on my Sony MD MZ55 and used as a signal generator.

The GREEN chart shows the direct sweep response with no EQ to the FT2000D radio via the front panel MIC connector driven from the "Full Rack" in bypass mode. It shows a relatively flat response to 4Khz where the DSP forms a TX "brick wall".

The BLUE chart shows the same sweep with the MIC2200 Preamp activated. This curve is almost identical to the GREEN chart except for the dip at 151hz from the one-stage EQ set to attenuate 151hz.

The RED chart shows the response employing the "full rack" (MIC2200+DEQ2496+DDP) all processors active. The response at 60hz is attenuated by -9dB; at 151hz, -25dB; at 951hz, -30dB; at 2.5khz, +3dB.

So the EQ is now verified using SINEWAVEs instead of white noise. The ESSB TX audio has low BASS smoothness and articulation with the rising HI FREQ response.

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The MP3 below was recored by Duke, NA1A using a FTdx9000 on 75mtrs. A little band noise but you get the idea!

"TTBF EQ" captured by NA1A

The SP chart made from an MP3 file captured by NA1A shows that it extends to 4Khz as is the "TTBF" mode. The mid-section is basically flat from 200hz to 3.8Khz and drops in level to 4Khz at the DSP's cutoff frequency.

Raw Mic Audio Captured - No EQ

DEQ2496 PEQ Settings

The EQ was born by capturing my voice via the TLM-103 w/ no EQ onto a Mini Disk. The recording was then captured by SP and a "raw" chart emerged. From this the "bad" spots were attenuated where needed including the low-mids. Only areas that needed EQ were 'touched' to remove "peaks". The high frequency area needed some added gain at 2550hz.

Octave BW vs Q

In the application here, it's relatively easy to determine the "Q" of the area that needs attention but the value that must be programmed into DEQ2496 has to be entered in "octave bandwidth". The chart shows how to translate "Q" into octave bandwidth. An example best shows how this is done. The area at "1497hz" in the above chart has a "Q" of 3.52. This is determined from this formula:      Q = fo / (f2 - f1)    where fo = center frequency; f2 = upper frequency; f1 = lower frequency. So here the Q = 1497 / (1710 - 1285) = 3.52.    Referring to the chart, the BW required to cover that area lies between 1/2 octave and 1/3 octave. The best choice is 1/2 octave since that ensures best "coverage" of the center frequency and all surrounding frequencies between f2 and f1. Of course, you could use 1/3 octave if the ends points don't require a lot of attenuation.

Proper Use of the SSB Speech Processor

A word . . .or two . . .about the use of the FT2000 speech processor. It's pretty simple but worth explaining for those who might not know esp some of the newcomers. The "only" rule is to . . . NOT . . . use the same setting you use for "hi-fi" SSB. Using the "wide" [1-30 or 3000WB] setting for Dx chasing does not work. The reason is simple; the SSB speech processor clipping products for low frequencies end up lying in the audio passband. This causes the SSB Tx audio to sound very muddy and distorted. So make sure that audio sound that you want for "DX" chasing is tailored by removing all frequencies below 200hz to 400hz. Such tailoring is setup in the PE1 thru PE3 [#134 thru #142] values in the FT2000 setup table above. If you use these values, you can be assured of high-penetration SSB audio that is "loud" and "clear"! To use the processor, select the "3-27" [300hz - 2700hz] setting and press the "PROC" button until "MIC EQ" and "PROC" are displayed in the VFO window. Adjust the PROC knob until 5 - 7dB is displayed on the meter with the selection set for "COMP". Listen with the headphones so that you can adjust it properly.

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. . How to compensate SpectraPlus Pro for BW Rolloff . .

SpectraPlusPro-SC (SP Pro) is a very powerful and user friendly spectral analysis program that can correct the BW rolloff present in all radios. Some are much flatter than others but all need some compensation. This note shows an easy way to accomplish this compensation. The file here will compensate the FT2000's "Phones" jack for 50hz to 5Khz. An excerpt from the "FT2000 Rx & Tx White Noise Sweep - TTBF" shows the extreme rolloff from the FT2000's PHONE jack output [2nd BLUE line] of -18.5dB @ 4Khz! Obviously not useable. This section shows how to generate the compensation file that will correct for lack of flatness. First, make af "text" file (using NotePad) that looks like the file at the right. This file is called a "MIC" compensation file and is located in the "miccomp" folder under the SP Pro folder. There are some files that can be edited and used as a starting point. Referring to the file at the right, the file contains lines that represent "frequencies" and the amount of compensation that is required. For example, "2500" represents 2.5Khz and "-8.0" represents the amount of correction, in dB, that's required to flatten the response. After adding the frequencies that are needed for your application, save the file giving it a name such as "Rx_Cal.MIC". The suffix "MIC" is mandatory. Save it in the "miccomp" folder. Next, with SP_Pro active, press "F4" and select "Scaling". Next place a check mark in the lower box labeled, "Enable Compensation". Then use "Select" to browse to the file that you created. Once found, click "OK" to enable its use. Now run the SP program. Select "Rec" and make sure that the input to your sound card is connected to the radio's output jack labeled "Phones". Make up a cable with a 1/4" stereo phone plug to mate with the FT2000 and a mini plug on the other. When the compensation values are correct, SP Pro spectral analysis should make a "straight" line across the laptop's screen showing a flat response from 50hz to 5Khz.

Audio Dynamics Processors and Settings:
As you have seen, my current goal to minimize the use of external equipment so as to produce a more natural sound. As a consquence three (3) audio dynamics boxes have been removed and the "rack" repacked to contain all of my current "audio" devices. This section details the current ones in use along w/ their strong points. At the end the current settings are shown for each.
MIC2200 Preamp:
A key box that will never (??) be replaced is the "preamp". It's the top box in the photo above. The current one is the Behringer UltraGain 2200. It contains a tube ("GT" Electronics) preamp that produces a warm sound. The main advantage is a one stage parametric (boxed in red) EQ that allows full control of the mic's input signal and pre-processes any frequency from 20hz to 10Khz with "attenuation" or "gain". I use it to remove the heavier low-mid frequency range (150hz to 300hz) BEFORE it gets into the following stages.

The picture shows a closeup of the controls of one of the two separate preamp sections. The preamp features tunable low cut (from 32hz to 320hz) for removing low "rumble". Currently it's set to 60hz. The parametric equalizer is fully tunable from 20hz to 20Khz with Q and level control. Currently set to 150hz with a Q = 1.0 (BW of 1 octave) and level of -12.5dB.

DEQ2496 Ultra Curve:
The single replacement for the removed audio dynamics processors is the Behringer DEQ2496.   It's the second box down from the top in the photo above. This is now my primary audio processor and I can say that it's a marvelous piece of DSP hardware and software. It tailors the audio dynamics not only based on "frequency" but also "level", so the EQ can change as a function of the input signal level! It can raise or lower the level of a specific frequency (or a band of frequencies) based on two parameters, "Gain" and "Threshold". Other parameters control the speed of how this is done.

The standard usage of this device is to "lower" the gain above a certain level however many are not aware of another way of using the DEQ processor. That is to use it to "RAISE" the level rather than lower it. It has some advantages that would be hard to accomplish with a 'standard' audio dynamics equipment over a wide frequency band.

An example shows how this happens. Setting the "M-Gain" to a positive number (+10dB) means that as soon as the level drops BELOW the "Threshold" (-23dB), the gain is increased by the amount of the M-Gain number, 10dB. When the input signal level goes above the "Threshold", it is reduced by -10db to the "normal" value.  The results are a louder audio almost as if it was 'compressed' for low (soft) mic input levels.

Another way is take advantage of the DEQ's power is to use the shelving filter, "H12" (high-pass, 12dB/oct) or the "L12" (low-pass, 12dB/oct) rather than the bandpass filter, "BP". This results in a larger region of controlled gain audio.

In DEQ #1, the H12 shelving filter attenuates all frequencies above 100hz. In DEQ#3 as shown on the right, the L12 shelving filter results in all frequencies below 2000hz being attenuated when signal level crosses the threshold level. This is a novel way of damping frequencies across a large frequency spectrum, 50hz to 2000hz.

Currently using the H12 settings for DEQ #1(Lo Freq) and DEQ #3 (Hi Freq). DEQ#2 (Mid Freq) uses the BP function. Check out my "Current Audio Settings" table below. Try them, they should at least get your SSB audio into the ballpark.

dbX Digital Dynamics Processor (DDP):
My seccondary processor is the DDP. This is the third box down from the top in the above photo. This is an excellent DP and there's no plans to replace or remove it. It has the necessary audio dynamics functions such as Gate, Equalizer, Compressor and Limiter. Currently, just the Gate and Compressor are being used. The DDP is a DSP device and it has an extremely clean response with no audio coloration which is key for any good audio dynamics processor.

DDP Transient Capture Mode Unlike analog technology with its response speed limitations regarding changes in amplitude, digital signal processing permits differences in amplitude to be identified in advance but you must use a bit of signal delay. Increasing this delay also increases the potential for the intelligent control. Even “looking ahead” by only a few samples is sufficient to ensure the intelligent application of dynamic processing – such as limiting, which ensures an absolutely reliable signal ceiling – without clipping. The DDP's Transient Capture Mode (TCM) works on the principle of delaying the audio signal and letting a 'control' signal begin to activate the response of the VCA (Voltage Control Amplifier). The overall result is the perception of a very fast moving compressor that is able to catch the front of almost every transient signal, but not delaying the audio signal enough to produce any phase correlation errors. The DDP can vary the delay with the range from 0us to 3ms. This gives the processor enough time to react before the signal arrives at the point of processing. The controls for TCM lie in the GATE parameter area. This effect is global but the GATE MUST be turned on in order for the TCM module to work. The implementation in the current DDP allows the signal to sound smoother and makes it much easier for the DDP to process the COMPRESSOR, LIMITER and DE-ESSER functions b/c it can capture all transients.

Current Dynamics Settings:
The table above shows my current audio dynamics settings for easy reference. As you see, all settings are changed regularly b/c there are no "sacred" positions. These settings may need to be 'tweaked' abit for your particular radio and microphone but they should get you in the ballpark.

Please note that my FT2000D has the low frequency mod shown
here that is reflected in the DEQ2496 settings below.

[Current Audio Settings for FT2000D: 04/15/20]
These settings are for the "Full_Rack_EQ" using the updated FW: 11.54 EDSP; Main 1.58/1.59

All settings here require the use of the "TTBF" [50hz to 4Khz] mode [Menu#85]. The DEQ LO (low freq) EQ uses L12 shelving filter and the DEQ HI (Hi freq) EQ uses the H12 - shelving filter. The BP mode is now used for DEQ MID (mid freq) EQ. Most DEQ2496 settings have changed including DYN Expansion, Limiter and Utility #1 settings have been re-adjusted.

In the dBx DDP, EQ is running in the "Bright" mode to add sparkle. The LIMITER provides a 'clamp' that actually limits the drive signal without clipping the signal. That allows it to generate in-your-face sounding ESSB audio w/o overdriving the FT-2000D input.

Behringer Ultra Gain Pro MIC2200 PreAmp: Phantom: On (+48V); [Phase Reverse; OUT (OFF)]; [Gain= +37.0dB]; [Cut: On, 60hz]; [Parametric Eq: Fr= 150, x1 (150hz), BW= 0.95, Level= -10dB]; [Output= +0dB] Behringer Ultra Curve DEQ2496: - [All PEQs are "Param"] [PEQ #4; Freq=151hz, BW=1/4, Gain=-4.0dB; PEQ #1; Freq=351hz, BW=1/3, Gain=-4.0dB; PEQ #8; Freq=3475hz, BW=3/4, Gain=+7.0dB]; [GEQ #1 thru #6; Freq=20hz thru 63hz, BW=1/3, Gn=-6.0dB] [DEQ: #1- Gn=0.0db; Thr=0dB; Rat=1:2.0; Atk=0.00ms; Thrs=0dB; Rel=177.2ms; Mode=L12; Freq=71.0hz <-- Lo Freq #2- Gn=0.0db; Thr=0.0dB; Rat=1:2.0; Atk=0.00ms; Thrs=0.0dB; Rel=177.2ms; Mode=BP; Freq=151hz; BW=3/4 <-- Mid Freq #3- Gn=+3.0db; Thr=-20dB; Rat=1:3.0; Atk=0.03ms; Thrs=-20dB; Rel=180.9.7ms; Mode=H12; Freq=2547hz] <-- Hi Freq [DYN: Expander; Gn=0.0dB, Thr=-21dB, Rat=1:3.0, Atk=0.00ms, Rel=180.9ms; Limiter; Hold=1.0ms, Thrs=-8.0dB, Rel=150.1ms] [UTIL #1: Gain Offset EQ; +8.0dB dBx DDP: [Common for Compressor and Gate: Atk: 0.1us; Hld: 220ms, Rel: 360db/sec] [Compr: OverEsy: Off, Auto: Off, Thrs: -27dB, Rat: 1.4:1, Gain: 3.0db] [Gate: Thrs: -27db, Rat: 1:4, TCM:On, Time: 2.0 msec] [Equalizer: Mode: Bright; Band1: Fc=80hz; Q=8.0; Lvl=2db; Band2: Fc=2.50khz; Q=4.0; Lvl=4; Band3: Fc=4.00khz; Q=4.0; Lvl=4db] [Limiter: Thres:-16dB; Atk: 0.1us; Rel: 300db/sec] [De-esser: OFF]

Note: The settings here are for use with the "Full_Rack_EQ". Make sure to turn OFF the radio's EQ settings.

Check back regularly for the latest updates.

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. . Standard Sweep Test Setup . .

The photo [Click to Enlarge] shows the hookup that I use to sweep my audio rack. The inset photo shows the output signal into my laptop for recording. A MP3, WAV files are generated as well as a SpectraPlus Pro spectral analysis chart. By leaving the XLR termination in the MIC line, I can remove the mic and easily insert the sweep test setup without having to take the audio rack cabinet apart. The Sony MiniDisk (MZ55) recorder previously recorded all of the needed "stimulus" signals such as a sinewave sweep (20hz to 6Khz), white and pink noise (20hz to 20Khz) sweep signals. Shown is a WHITE noise sweep underway. The connection is made as shown through a 40dB PAD into the 'MIC' input of the Behringer MIC2200 Preamp. From there, by activating the appropriate 'bypass' buttons on each processor, it's possible to see the individual contribution from each studio processor (MIC2200, DEQ2496 and dBx DDP) as reflected in the spectral analysis. Then by adding each processor back 'inline', you can see the contribution from each stage into the final EQ response. This is a very staightforward way to use a MD as an accurate "signal generator". The MD is flat from 20hz to 20hz so it serves as an accurate "signal generator". Spectraplus Pro is also flat using the laptops (Dell D630) audio amplifier.