The damper on your 20g eff mass 750D allows you to use carts that wouldn't ordinarily be recommended. Changing to a lighter or heavier headshell will effect mass, but not quite as a direct addition or subtraction. Only the change at, or further forward of the cart will directly change mass. So a change of 5g might change eff mass by 4.
I suspect you'll get best results with a 103(D) that has low cu and is often paired with the 750D. With the damping, I've read about people using relatively high cu carts like the AT-OC9II and 150MLX. These both have 100HZ cu of 10 which is equal to about 18cu at standard 10Hz. Denon also uses 100Hz cu and the conversion isn't straightforward. A 100Hz cu of 6.5 = 15 @ 10Hz. The DL-110 is the next lowest cu, it's 8 @ 100Hz. With some damping you could probably use this with no problem. Although the rest of the line has much higher cu, they seem to do best in med mass arms. You could probably get pretty good results with any of them. You might want to get a lighter headshell and use the damping for some, but the 750D and the 103 is a marriage made in heaven, if you believe what you read.
Regards,
I suspect you'll get best results with a 103(D) that has low cu and is often paired with the 750D. With the damping, I've read about people using relatively high cu carts like the AT-OC9II and 150MLX. These both have 100HZ cu of 10 which is equal to about 18cu at standard 10Hz. Denon also uses 100Hz cu and the conversion isn't straightforward. A 100Hz cu of 6.5 = 15 @ 10Hz. The DL-110 is the next lowest cu, it's 8 @ 100Hz. With some damping you could probably use this with no problem. Although the rest of the line has much higher cu, they seem to do best in med mass arms. You could probably get pretty good results with any of them. You might want to get a lighter headshell and use the damping for some, but the 750D and the 103 is a marriage made in heaven, if you believe what you read.
Regards,