In this review, we will be comparing BalancedForce 210 and KUBE 10b, two Powered Subwoofer speakers  from MartinLogan and KEF. Being Powered subwoofers, they both have built-in amplifiers so you don't need an external power amp or an integrated amp to power them.         Let's have a brief look at the main features of MartinLogan BalancedForce 210 and KEF KUBE 10b first before getting into our more detailed comparison.
        
     
    
        
            In the following sections, we will get into details in order to better understand how the MartinLogan BalancedForce 210 and KEF KUBE 10b compare and hopefully end up with enough arguments to decide which one of these subwoofers is the better choice for you.
        
        
            
            
            **This post contains affiliate links, and I will be compensated if you make a purchase after clicking through my links. As an Amazon Associate I earn from qualifying purchases.
            
            
         
         Drivers
        
            The efficiency of a subwoofer  is directly proportional to the total radiating are squared hence the woofer quantity and diameter.MartinLogan BalancedForce 210 and KEF KUBE 10b have a totally different setup: the MartinLogan BalancedForce 210 features 2 x 10-inch drivers whereas the KUBE 10b features 1 x 10-inch drivers.         
         Frequency Response
        
            BalancedForce 210 has a frequency range of   20-120 Hz whereas KUBE 10b has a frequency range of 24-140 Hz.  With a minimum frequency of 20Hz, the BalancedForce 210 can go slightly deeper then the KUBE 10b's min frequency of 24Hz. 
Below graphs depict how these two speakers compare with the max, min and average values of the Min and Max Frequencies of other speakers in the Subwoofer class in our database.         
        
            
                Low Frequency
                Subwoofer Speakers
                
                    
                        MartinLogan BalancedForce 210
                    
                 
                
                
                
                
             
            
                High Frequency
                Subwoofer Speakers
                
                    
                        MartinLogan BalancedForce 210
                    
                 
                
                
                
                
             
         
        
        
        
        
             Cabinet Type
            
                 Both MartinLogan BalancedForce 210 and KEF KUBE 10b have Acoustic Suspension type cabinets. Acoustic Suspension aka Sealed type subwoofers have enclosures that are sealed hence no ports or holes exists on the cabinet. Sealed designs helps to provide more accurate and tight bass responses compared to ported designs.             
        
                
        
 Physical Specs 
		 Size of a speaker can sometimes become an important decision factor due to space constraints or in some cases purely for esthetic reasons. In this section, we are going to compare MartinLogan BalancedForce 210's and KEF KUBE 10b's external dimensions. MartinLogan BalancedForce 210 has external dimensions of 485.0 x 486.0 x 543.0mm ( 19-1/16inch x 19-1/8inch x 21-3/8inch )  whereas KEF KUBE 10b has external dimensions of 372.0 x 356.0 x 397.0mm ( 14-5/8 x 14 x 15-5/8inch) .
 MartinLogan BalancedForce 210 is clearly the larger of the two speakers. Its body is 130mm wider, 113mm taller and 146mm deeper than KEF KUBE 10b. 
    
        Base Surface Area Comparison
        Base surface area of a loudspeaker may become a  determining factor when the space in your room or desk is limited.
        The base surface area of the MartinLogan BalancedForce 210 is approximately 2639.0cm2 / 409.0inch2 and          base area of the KEF KUBE 10b is approximately 1413.3cm2 / 219.1inch2.         The BalancedForce 210 requires 87% more surface area than the KUBE 10b which gives it a small disadvantage on placement in tight spaces.      
 
        
        
        
        
        
Weight Comparison The weight of a subwoofer may become an important factor if you need to move and reposition the unit often to find the optimal positioning, also known as 'Subwoofer Crawling'. The MartinLogan BalancedForce 210 weighs 43.64kg / 96lbs and the KEF KUBE 10b weighs 17.50kg / 38.5lbs. This makes the BalancedForce 210 149% heavier than the KUBE 10b. 
Here is a comparison of how BalancedForce 210 and KUBE 10b's weights compare with the average, max and min weights in Powered Subwoofer class.
    
        Weight
        All Subwoofer Speakers
        
            
                MartinLogan BalancedForce 210
            
         
        
        
        
        
     
     
                    
            
 What's in the Box of MartinLogan BalancedForce 210? 
            Here are the items that are included inside the box of BalancedForce 210:
            
Powered subwooferTop-glass cover2 Grilles8-feet AC power cord4 Spike feet4 CollarsUSB thumbdriveUser-feets ManualOnline Registration Card            
            
            
 What's in the Box of KEF KUBE 10b? 
            Here are the items that come with the KUBE 10b:
            
Powered subwoofer6.5-feet AC power cordSpeaker-level input blockUser ManualImportant Safety InformationWarranty Information            
        
     
                    
                                        
                    
                        
                        
                            
                                                            
                                    |  Number of Woofers | 2
                                        vs
                                         1 | More woofers | 
                                                            
                                    |  Low Frequency Response | 20 Hz
                                        vs
                                         24 Hz | Generates deeper bass | 
                                                        
                        
                    
                    
                        
                        
                            
                                                            
                                    |  Driver Setup | 1-way
                                        vs
                                         -way | Have a dedicated mid-range driver | 
                                                            
                                    |  High Frequency Response | 140k Hz
                                        vs
                                         120k Hz | Generates higher frequency | 
                                                            
                                    |  Height | 372mm
                                        vs
                                         485mm | Easier to fit in smaller spaces | 
                                                            
                                    |  Base Surface Area | 1413cm2
                                        vs
                                         2639cm2 | Takes less floor space | 
                                                            
                                    |  Price per pair* | 750USD
                                        vs
                                         3499USD | costs less (*prices may change depending on the seller, location and time) | 
                                                            
                                    |  Wireless Operation | Optional
                                        vs
                                         No | Connect your subwoofer to your system wireless | 
                                                        
                        
                    
                    
                        
			
			
				
					| General | MartinLogan BalancedForce 210 | KEF KUBE 10b | 
						| Brand | MartinLogan | KEF | 
					
						| Speaker Type | Powered Subwoofer | Powered Subwoofer | 
                    
                                            
                            | Max Amplifier Output | 850 watts | 300 watts | 
                    
                                        
                    
                    
                        | Frequency Response | 20-120 Hz | 24-140 Hz | 
                                        Amplifier |  |  | 
                        | Watts RMS (Continuous) | 850-watt RMS | 300-watt RMS | 
                
                                    
                        | Watts Peak (Max) | 1700-watt RMS | n/a | 
                
                
                
                
					
					
					Drivers |  |  | 
                        | Woofer Quantity | 2 | 1 | 
                
                    | Woofer Size | 10" | 10" | 
                    
                        | Woofer Composition | Aluminum | Not given | 
                
					
                        | Tweeter Size | - | - | 
                
					
					
                    
                        | Aimable Tweeter | No | No | 
					
					
                        | Midrange Driver | No | No | 
                                    
                        | Crossover Frequency | n/a | 40-140 Hz | 
                
                                    
                        | Firing Direction | front | front | 
                
                
					
					Physical Specs |  |  | 
                        | Height | 485.0mm (19.1") | 372.0mm (14.6") | 
                
                    | Width | 486.0mm (19.1") | 356.0mm (14") | 
                
                    | Depth | 543.0mm (21.4") | 397.0mm (15.6") | 
					
                					
                        | Weight | 43.64kg (96lbs) | 17.50kg (38.5lbs) | 
                					
                    | Enclosure | Acoustic Suspension | Acoustic Suspension | 
                
                                    
                        | Available Colors | Gloss Black, Black Ash | n/a | 
                
                
                                                    
                        | Grille | Yes | n/a | 
                					
                        | Moisture Resistancy | No | No | 
                
					Connections |  |  | Other |  |  | 
                    | Parts Warranty | 3 Years w/ Registration | 2 Years | 
					
					
                    | Labor Warranty | 3 Years w/ Registration | 2 Years |