You can always change fans ... however... both those coolers... and just about every CLC use very low flow pumps and aluminum radiators which have a very low heat transfer coefficient. In order to make up for those deficiencies, they need to compensate with very high (noisy) fans. Using a lower rpm fan will reduce noise, but it also impacts thermal performance. So taking a $110 cooler and adding $50 worth of slower fans to reduce noise, will inevitably lead to lower thermal performance. Mixed metals (aluminim rad and copper block) also causes galvanic corrosion
Best to save money and buy a unit with copper rads, no mixed metals and expandability to add water blocks for GFX cards and you solve your problem and get a significant...