Diamond Alter bow review and tuning tips:
I like this bow so much that I actually bought two of them (RH, 70 lbs max only, 330 fps IBO, 31.5" ATA, 7" BH, 4.1 lbs, 10 limb bolt turns max, limb stop only, binary cams). The Alter is actually 4 bows in one because it has Comfort/Performance swap disc technology AND an "grow-with-you" A vs. B cable routing mode. A mode lets you reach the top end of the draw length adjustment (31") and B mode lets you reach the bottom end of the adjustment (21"). But it also lets you convert the 70 lbs max bow into a 60 lbs max bow, or there abouts. The first one I set up in B mode for a 60 lbs max draw, but then out grew it a bit so switched from the stock Comfort mode to Performance mode (swapping the stock modules top and bottom) for a draw cycle that increases in the last third and increases speed (approximately 10 fps reported). Holds and shoots fantastic.
So I bought another one to set up in A mode Comfort mode to work my way up to a full 70 lbs bow. This one is also a fantastic shooter with more resistance in the first third of the pull that smoothes out in the last half of the pull. I am almost there at just one turn out. If I outgrow it at the full 70 lbs, I can then swap the modules to Peformance mode.
However, both required lots of tuning. Both had severe nock right tears (bare shaft into foam) and needed a lot of cam shimming to the right. One needed a 0.032 shim at the bottom draw weight limb pocket locking screw to shift the lower limb tips more square to the left and to help correct the nock right tear, and the other needed left lower limb fulcrum shimming for what I think was a slightly weak left lower limb to help correct the nock right tear.
Both shot nock high which didn't respond to arrow rest changes, but DID respond to 1/4 turn out on the top limb bolts (tiller tuning). Although the Alter has equal binary cams (with two equal length cables), the bowstring center lines up with the arrow shelf, 2 cm below the nocking point/arrow rest. I believe this is why the Alter holds so well compared to my PSE Evolve 31 which has its nocking point in the center of the bowstring and arrow rest, well above the grip. Maybe the tiller adjustment corrects for the Alter's above bowstring center nocking point? The advantage of the equal length cables is that once adjusted to be in time, the cams never go out of time.
The Alter has one limb stop and no cable stops for a solid repeatable back wall. The cams are marked for precise cam timing at brace for both A and B modes.
So both of my Diamond Alter bows in different modes shoot great with excellent hold/aim/accuracy with different draw cycles on the same familiar platform. At the midrange price I can own two Alters for the price of one flagship bow and have the perfect back up bow always ready to go. I am an archery hobbyist who likes to tinker and tune bows to perfection, so I actually found the tuning process gratifying and worthwhile. However, if you want a bow that will shoot bullet holes right out of the box without any tuning or cam shimming, this may not be the right bow for you.
I like this bow so much that I actually bought two of them (RH, 70 lbs max only, 330 fps IBO, 31.5" ATA, 7" BH, 4.1 lbs, 10 limb bolt turns max, limb stop only, binary cams). The Alter is actually 4 bows in one because it has Comfort/Performance swap disc technology AND an "grow-with-you" A vs. B cable routing mode. A mode lets you reach the top end of the draw length adjustment (31") and B mode lets you reach the bottom end of the adjustment (21"). But it also lets you convert the 70 lbs max bow into a 60 lbs max bow, or there abouts. The first one I set up in B mode for a 60 lbs max draw, but then out grew it a bit so switched from the stock Comfort mode to Performance mode (swapping the stock modules top and bottom) for a draw cycle that increases in the last third and increases speed (approximately 10 fps reported). Holds and shoots fantastic.
So I bought another one to set up in A mode Comfort mode to work my way up to a full 70 lbs bow. This one is also a fantastic shooter with more resistance in the first third of the pull that smoothes out in the last half of the pull. I am almost there at just one turn out. If I outgrow it at the full 70 lbs, I can then swap the modules to Peformance mode.
However, both required lots of tuning. Both had severe nock right tears (bare shaft into foam) and needed a lot of cam shimming to the right. One needed a 0.032 shim at the bottom draw weight limb pocket locking screw to shift the lower limb tips more square to the left and to help correct the nock right tear, and the other needed left lower limb fulcrum shimming for what I think was a slightly weak left lower limb to help correct the nock right tear.
Both shot nock high which didn't respond to arrow rest changes, but DID respond to 1/4 turn out on the top limb bolts (tiller tuning). Although the Alter has equal binary cams (with two equal length cables), the bowstring center lines up with the arrow shelf, 2 cm below the nocking point/arrow rest. I believe this is why the Alter holds so well compared to my PSE Evolve 31 which has its nocking point in the center of the bowstring and arrow rest, well above the grip. Maybe the tiller adjustment corrects for the Alter's above bowstring center nocking point? The advantage of the equal length cables is that once adjusted to be in time, the cams never go out of time.
The Alter has one limb stop and no cable stops for a solid repeatable back wall. The cams are marked for precise cam timing at brace for both A and B modes.
So both of my Diamond Alter bows in different modes shoot great with excellent hold/aim/accuracy with different draw cycles on the same familiar platform. At the midrange price I can own two Alters for the price of one flagship bow and have the perfect back up bow always ready to go. I am an archery hobbyist who likes to tinker and tune bows to perfection, so I actually found the tuning process gratifying and worthwhile. However, if you want a bow that will shoot bullet holes right out of the box without any tuning or cam shimming, this may not be the right bow for you.
