I have to take issue with:
but nowhere near the quality or quantities that expansions do
I find that the V3 provides very high quality sounds and a considerably more programmable and controllable interface than the BK7. It provides a specialist expander for European and Celtic sounds, amongst others, none of which are adequately catered by the BK7. It's a 'horses for courses' situation.
I never said that the V3 is a bad arranger in any manner and I don't take issue with opinions. "Better" really depends on the specific needs, of the user, and I did mention that from the factory the BK does not have the selection for Irish/Scottish music. More properly said, I should have used the term Celtic "styles". In terms of European rhythms, no, the V3 cannot come close to the factory installed ones in the BK. There is a greater selection and the quality is as good if not better. And if the accordion being used is a Roland, there are several more undisputed advantages to choosing the Roland BK over the V3.
However, let's look at a few traits of both models:
Manual PDF size. Now, this might mean little, except that if one manual has a significantly more pages, it means it has greater options or choices.
V3 - 71 pages.
BK - 128 pages.
Ok, perhaps it's not important.
Let's look at the number of instruments available to your right hand that you have from the factory:
V3 - (as per page 65 of the manual) 30.
BK - (as per page 93, 94 and 95 of the manual) a touch over 1,000.
Let's look at the number of drum kits/ sets available from the factory:
V3 - Unspecified.
BK over 90 completely different drum ensembles (pages 96-103)
Can it record your performance?
V3 - No.
BK - Yes.
Wizard connection tp make setup simple?:
V3 - No.
Drum solo and/or variations?
V3 - 4.
BK - 4.
However, on the V3, you have 2 pedals for 4 functions. On the BK you have a switch per variation and function. Where to get from one variation to another on the V3 sometimes takes 2 presses. On the BK you can go anywhere between 1,2,3,4 with a single press. There are also pedal switches for Start/Stop, Intro and End. On the V3, start/stop, but not for Intro nor End. Also, the V3 cannot use for example, Intro variation 4, and automatically move to variation 1. BK does this easily.
Maximum # of foot pedal switches and functions supported:
V2 - 3 pedals with 5 functions.
BK - 2 pedals with 8 functions
On a Roland V-accordion, it uses MIDI channels 1, 2, 3, 4, 5, 6, 7. Can the arranger map to these specifics?
V3 - No.
BK - Yes.
Midi ch: Function:
1 - Treble > UP1
2 - 2 -Bass > MBS + Note to Arranger
3 - Chords - LWR + Note to Arranger
4 - Orchestra > UP2
5 - Orchestra Bass - Note to Arranger
6 - Orchestra Chords - Note to Arranger
7 - Orchestra Free Bass - Note to Arranger
Integrated Music styles:
V3 - 300 (page 14).
BK - Over 400 (pages 88-90) However, there are literally thousands of free styles available off the internet and on ebay one can purchase literally a USB key with over 10,000 styles for the BK for a relatively small sum (under $75US). You cannot fund more styles for the V3 than come with the unit.
V3 - 4
BK - 2
That said, the BK and adjust the setting of ANY sound from full left to full right and anywhere in between in 64 steps per side.
V3 - 0
BK - 2
This means that when playing in a band, you can plug in your BK in to the mixer using only 2 channels and plug your V-accordion in to the BK and not use any additional channels on the mixer. One can adjust the balance between your V-accordion and backing module via rotary dial. In a similar setup, one needs a minimum of 4 mixer inputs for a stereo signal from the V-accordion and arranger.
V3 - Preset or adjustable via buttons
BK - Preset or adjustable via buttons OR rotary dial OR tap button.
V3 - Two SD cards, only one can be used at a time
BK - Internal SSD or external USB key, maximum 128gb.
Now, I am not sure, but what happens if your SD cards drop out in transit or are stolen? No arranger. The BK uses solid state internal storage and cannot be removed. The USB is not mandatory for the functionality of the BK, but I *believe* that the SD cards are for the V3.
Performance List: A Performance List is a list of up to 999 Performance memories. Each Performance memory contains a reference to the desired Music Style or song and all settings you want to load along with that Music Style or song, including
settings like INTRO/ENDING status, selected VARIATION, different instruments, etc.
V3 - No.
BK - Yes.
Can the Arranger record your backing tracks to a USB drive to be later simply inserted into a V-accordion so that the musician can play along without needing the arranger?
V3 - No.
BK - Yes.
As a matter of fact, one has the choice of capturing both the V-accordion AND the arranger at once or just the arranger alone to a USB stick as you play. This means you can literally pre-record your backing tracks, plug them in to your accordion and "stroll" around, using only the V-accordion's internal speakers and file player and not need to plug in to any arranger, yet still play along with the BK's backing tracks.
Can the arranger receive data from a computer via MIDI?
V3 - Well it does have a MIDI in port, however, no mention of it can receive/understand data from a computer/DAW.
BK - Yes, it even comes with SONAR, and indeed, you do not need to purchase a computer MIDI interface, you can use the USB port of the BK to connect to your computer, saving you money.
The V3 refers to it's "processors" as plug-ins. The BK refers to it as MFX parameters.
V3 - 29 parameters, of which only 21 are defined. (page 37)
BK - 83 defined parameters (page 106 - 122)
Ok, my fingers are getting tired, and I am only about 3/4 way through the manuals... lol
There is one last thing that I want to mention, though... and that's the actual user interface that the owner touches. On the V3, it uses old fashioned plastic covered buttons, the kind we know that over time the plastic will harden and crack, exposing the switches. The BK uses large firm buttons and a textured dial, controls that have been proven to last way longer than the plastic covered styles that were used in the 70's on (for example) remote controls.
Now, I am not even experienced with either arranger and just by reading quickly through the manuals, I am finding it hard to see where anyone could find issue with my statement that the BK-7m isn't pretty much more of EVERYTHING that the V3 is except for the existence of one set of Celtic rhythms (though the BK does contain Celtic presets, reference page 48).
If only ONE style is the only place the V3 is superior, then the fact is, it would only be the better choice of arranger if your style depended on these Celtic styles. However, the BK is better in so many other areas, but again, to be fair, if you don't need or use any of those other areas, they aren't important.
Basically... it would be good to look at both before making a choice, if you were looking at backing modules, but in terms of options, features and functionality, the winner is easy to point to by looking no further than the manuals.