Maybe I simply do not know enough about Basses, but many of Dim Pro's basses will not play below B2 Flat. Others will. I thought the 4 string bass was usually tuned to E1 on the open bottom string.
 
Thanks for any advice.

Modify the sfz files, the key setting in the MIDI DPro track and base octave display in Preferences to suit your needs. Did you check the fundamental frequency of the notes played? Using the defaults, the first Bass program 03 - Real Basses > Dull Fingered 1.prog shows E3 playing at ~41Hz which is open E using standard tuning on a 4 string electric bass. The program also plays down to ~29Hz which by default displays B2b.

Thanks for the reply, mate.
 
Ah. Ok. I thought E_1_ was 41Hz. Some of the programmes agree with me and let me play it. Others, like the one you cite, set it lower. I need to delve into sfz's again and see if I can standardise them to what I understand.
 
 

In the analog world E1 is 41Hz. You were asking about DPro in SONAR. Remember sfz works with MIDI note numbers and maps those numbers to samples. How MIDI note numbers relate to pitches displayed in SONAR is set by "Base Octave for Pitches" in Preferences > Customization > Display. You could modify the sfz files, adjust the Key+ slider in the track inspector to make programs appear to play in a certain range, or change the display. I believe the Key+ slider is less work than messing with sfz files and more targeted than the global change in Preferences. Granted changing the sfz files is a one time event.

I obviously have some learning to do, as I am lost. Need to chew through this.

Thanks guys.

Many bass synths transpose the key mapping to sound an octave lower than normal on any given MIDI note number. This faciliates playing bass on compact keyboard controllers with a limited range. Most, if not all, Dim Pro bass patches do this. In addition, there is no universal standard for octave numbering.  SONAR labels Middle C (MIDI Note Number 60), C5. Some software/hardware vendors label it C3 or C4. SONAR's convention eliminates the need to use negative octave numbers to cover the full MIDI note number range.
 
The important thing is that the synth can play a low E at 41Hz, regardless of what MIDI note number or DAW octave that sample is mapped to.
 
As Steve indicated, if you want the bass part to display in the 'normal' octave in the PRV or Staff view, the easy way to do that is to enter +12 in the Key+ (Key Offset) setting in the MIDI/Instrument track for the bass.

Goodness! Thanks for that. I had never struck this before, although I have used DimPro a bit. Most of my historic use of sfz was back in the day...soundblaster etc. Very rusty :(
 
I will have a look at the offset, and try to see if the sfz's that don't give trouble are in a differentg scale, or they are just not limited in note range as much as others. 

brundlefly
In addition, there is no universal standard for octave numbering.  SONAR labels Middle C (MIDI Note Number 60), C5. Some software/hardware vendors label it C3 or C4. SONAR's convention eliminates the need to use negative octave numbers to cover the full MIDI note number range.

Although there is no universal standard that I am aware of, there is an international standard 
 
It's called Scientific Pitch Notation, American Standard Pitch Notation, or International Pitch Notation and it predates midi and goes back to 1926 - frequency tables were adopted by the Acoustical Society of America in 1939, and adopted by the International Organization of Standardization in 1955. According to the standard A4 is 440 Hz and that makes middle C - C4. Unfortunately many musical instrument manufacturers did not follow the standard. FWIW. 
 

rsinger
Although there is no universal standard that I am aware of, there is an international standard 
 
It's called Scientific Pitch Notation, American Standard Pitch Notation, or International Pitch Notation and it predates midi and goes back to 1926 - frequency tables were adopted by the Acoustical Society of America in 1939, and adopted by the International Organization of Standardization in 1955. According to the standard A4 is 440 Hz and that makes middle C - C4. Unfortunately many musical instrument manufacturers did not follow the standard. FWIW. 
 

 
 AHAH! I now see my confusion. Having been used to Piano, guitar and other "real life" :) instruments, as well as my High School Physics, that standard is the one I know.
 
I tried the Transpose ?Key+ setting and my brief efforts say it _seems_ to have solved my trouble in a practical way.