On December 1, 2014, when asked about VOCALOID4 updates, Noboru responded that Internet Co., Ltd. wished to update all of their VOCALOID3s to the new engine but had no specific schedule at the time.
On March 31, 2015, Gackpo was announced to receive a VOCALOID4 update. This update contained his 3 voicebanks from the VOCALOID3 engine, but with added growl samples. It was confirmed that he would be released on April 30, 2015.
Gackpoid V4 software is an update of the VOCALOID3Gackpoid with added growl samples. It includes the following voicebanks: "Native", "Whisper" and "Power". Vocals can be purchased separately or as a complete package.
The package also contains demo song data and illustrations.
Vocal traits as noted:
More triphones added.
Quality overall improved.
The complete product is one of two vocal package recommended to go with Fukase, the other being Sachiko.
Software issues as noted:
Aside from GWL and a slight improvement in quality, this package offers nothing the previous V3 Gackpoid package didn't already offer. The reason for this is because no new recordings were done and the package was created by improving the old VOCALOID3 samples.
Cross-Synthesis as noted:
VOCALOID4's parameter XSY can be used on all 3 voicebanks within this package, as well as GWL.
In total the package offers the equivalent of 6 additional voicebanks achievable via XSY. The total tone variation offered by the package comes to a theoretical 9 voicebanks in total.
All XSY vocals work as explained on the V3 Gackpoid page, the main difference is the ability to use GWL with XSY and that the Gackpoid V4 package is overall better for XSY then the V3 Gackpoid package.
From Ver.4.3.0 of the Vocaloid engine, a XSY group "Internet" was added to Vocaloid. All vocals within the "Internet" group can XSY with each other. This vocal release is part of this group. If a User owns one or more vocals within the "Internet" group, XSY between them will open up as a result of owning this release.
The "Internet" group is currently the largest XSY group at 29 voicebanks. If old versions that have since been re-released are removed, there are currently 21 unique voicebanks. These are; "Gackpoid Native", "Gackpoid Whisper", "Gackpoid Power", "Lily Native", "Lily", "Cul", "Kokone", "Gachapoid", "Chika", "Otomachi Una Sugar", "Otomachi Una Spicy", "Megpoid Native", "Megpoid Sweet", "Megpoid Adult", "Megpoid Power", "Megpoid Whisper", "Megpoid Nativefat", "Megpoid Mellowadult", "Megpoid Powerfat", "Megpoid Naturalsweet" and "Megpoid Softwhisper".
In total if user was to own every VOCALOID3 and VOCALOID4 XSY capable INTERNET co., LTD vocal, this offers the equivalent of 812 additional voicebanks achievable via XSY. The total tone variation offered by the combined packages comes to a theoretical 841 voicebanks in total.
Note that Users of the updated XSY list have to understand that as confirmed by Internet co., Ltd themselves, depending on the combination of the two vocals a level of extra unwanted noise may be generated.
Another note worthy detail on V4 and later vocals compared to V3 vocals within this group is that Internet Co., Ltd. increased the number of triphones from Chika onwards. Thus, many newer vocals do not match sound-for-sound with the older pre-Chika released vocals.
Post VOCALOID4 releases were also developed with XSY in mind, so are better for XSY then the older VOCALOID3 releases.
In addition to not being built with XSY in mind, VOCALOID3 packages with only 1 vocal in their contents that were released may be even more problematic for XSY. Internet co often made multi-pack releases have a quality that made switching mid-song less noticeable between voicebanks, making them slightly better for XSY then single vocal releases.
Note that also "GWL" does not become viable for use with any V3 vocals used as the primarily vocal. This should be considered when using any vocal for XSY within the "Internet" group from V3.
The Gackpoid vocal is the only example of a true masculine result within the Internet group. It works best for the other vocalists in the secondary position and can help give more authentic masculine result from the other voicebanks in the group.
Due to the improvements over V3 Gackpoid, this is the better option for newer users then the V3 product.