In this review, we will be comparing S20 and TSi100, two Passive Bookshelf speakers  by Polk Audio
                
            Let's have a brief look at the main features
            of Polk S20 and Polk TSi100 first before getting into our more
            detailed comparison.
        
     
    
        
            Polk S20 Key Specs
            
							
                                - 2-way Design
- 1" Soft-Dome Tweeter
- 6.5" Mica-reinforced polypropylene Woofer
- 39-40k Hz Frequency Response
- 88 dB Sensitivity
- Impedance: 8ohms
- Power Range:20-125watts
- Weight:7.73kg
- Dimensions (H x W x D): 376.0" x 8.5" x 13.7"( 376.0 x 216.0 x 350.0mm )
 
        
            Polk TSi100 Key Specs
            
							
							- 2-way Design
-  1" Dome Tweeter
- 5.25" Organic Fiber Woofer
- 61-24k Hz Frequency Response
- 89 dB Sensitivity
- Impedance: 8ohms
- Power Range:20-100watts
- Weight:4.53kg
- Dimensions (H x W x D): 279.4" x 7.0" x 10.1"( 279.4 x 177.8 x 259.0mm )
 
     
    
                    
        
             What size room are the Polk S20                and Polk TSi100 speakers good for?
            
                The size of the room in which you are planning to use these loudspeakers is an important decision
                factor. Here we have compared their suitability to various sizes of environments considering their size
                and max power parameters:
            
         
        
            
                
                    
                    
                        | Listening Environment* | Polk S20 | Polk TSi100 | 
                    
                    
                    
                        | Near-field | Poor | Average | 
                    
                        | Small Room | Average | Good | 
                    
                        | Mid-size Room | Good | Average | 
                    
                        | Large Room | Average | Poor | 
                    
                        | Very Large Room | Poor | Bad | 
                    
                
             
         
        
             (* Approximate Room sizes: Small < 100sq. ft / 9 m2,
                Mid-size: 100-220 sq. ft / 9-20 m2, Large 220-400 sq. ft / 20-36 m2, Very Large: >
                400 sq. ft / 36 m2.
                Average Floor Height: 9" / 2.7m. Typical room sizes differ from country to country, and the actual
                listening experience changes depending on floor height, room shape, surface materials, listening
                position, speaker locations, etc.)
        
    
    
        In the following sections, we will get into more detail in order to better understand how the Polk S20 and Polk TSi100 compare and hopefully end up with enough arguments to decide which one of these loudspeakers 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
        
             Both S20 and TSi100 are 2-way speakers.         
        
            
                
                    
                    
                        | Driver | Polk S20 | Polk TSi100 | 
                    
                    
                    
                        | Driver Setup | 2-way | 2-way | 
                                        
                        | Tweeter | 1-inch | 1-inch | 
                    
                        | Midrange | - | - | 
                    
                        | Woofer | 1 x 6.5-inch | 1 x 5.25-inch | 
                    
                
             
         
         S20 features a 1" Terylene Soft-Dome Tweeter  and 1 x 6.5" Mica-reinforced polypropylene Woofer  with a Crossover frequency at  2500Hz.  On the other hand, the TSi100 features a 1"  Dome Tweeter  and 1 x 5.25" Organic Fiber Woofer  with a Crossover frequency at  2500Hz. 
     
    
         Frequency Response
        
            S20 has a frequency range of   39-40k Hz whereas TSi100 has a frequency range of 61-24k Hz.  With a minimum frequency of 39Hz, the S20 can go significantly deeper on the low side and provide stronger bass compared to the TSi100's min frequency of 61Hz. 
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 Bookshelf class in our database.         
     
    
        
            Low Frequency
            Bookshelf Speakers
            
            
            
            
            
         
        
            High Frequency
            Bookshelf Speakers
            
            
            
            
            
         
     
     None of these speakers achieves full range experience which is commonly agreed as 20Hz-20kHz. In order to achieve lower lows / deeper bass, we recommend you pair these with a subwoofer. Visit our Powered Subwoofers section to find out more about the available options.
    
         Impedance and Sensitivity
        
            S20 and  TSi100 have the same Impedance of 8 ohms  but where they differ is the sensitivity levels. S20 sensitivity is rated at  88 dB and the TSi100's is at 89 dB.  This 1 dB difference makes the Polk TSi100 a more sensitive speaker compared to Polk S20, hence will play louder  with the same amount of watts.         
        
        
            
                Sensitivity
                Bookshelf Speakers
                
                
                
                
                
             
         
    
            
            
            
 Power Range
            Power
                range is the range of input power in watts RMS that a loudspeaker is designed to handle. While using
            an amplifier within this range ensures the nominal performance , inputting a power that is higher than the
            max wattage can result in a damaged speaker.
            
S20 can handle a max power of   125 watts RMS from the amp the whereas TSi100 has a max power handling value of 100 watts RMS, 25 watts less than the S20.             
            Keep in mind that a higher max power handling value doesn't necessarily make that a louder speaker
                compared to a lower max handling speaker. Loudness or the sound level is also impacted by parameters
                such as Impedance, sensitivity and system efficiencies.
            
         
    
            
        
 Input Type and Bi-Amping / Bi-Wiring
        S20 features Pair of 5-way Binding Posts - Gold-Plated type posts and TSi100 has a Pair of 5-way Binding Posts - Gold-Plated type posts. None of these speakers feature bi-amping/bi-wiring.         
                        
        
    
             Cabinet Type and Port Position
        
            Both S20 and  TSi100 have rear firing ports. Rear ported speakers generally need more room between the backside of the speaker and the wall compared to sealed and  front/bottom ported speakers. Placing the speakers too close to the walls may cause the bass to sound boomy.
 If you are limited in space and can't get the speakers away from the backwall, check our  Speakers with Front Firing Ports page.
        
            
    
 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 Polk S20's and Polk TSi100's external dimensions. Polk S20 has external dimensions of 376.0 x 216.0 x 350.0mm ( 14.8 x 8.5 x 13.7inch)  whereas Polk TSi100 has external dimensions of 279.4 x 177.8 x 259.0mm ( 11.0 x 7.0 x 10.1inch) .
 Polk S20 is clearly the larger of the two speakers. Its body is 38.2mm wider, 96.6mm taller and 91mm deeper than Polk TSi100. 
		
			Below you can see the front view size comparison of Polk S20 and Polk TSi100 in scale.        
    
                 Comparison image of Polk S20 and Polk TSi100 Size and External Dimensions
    
        Comparison image of Polk S20 and Polk TSi100 Size and External Dimensions    
    
    
        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 Polk S20 is approximately 756.0cm2 / 117.2inch2 and          base area of the Polk TSi100 is approximately 460.5cm2 / 71.4inch2.         The S20 requires 64% more surface area than the TSi100 which gives it a small disadvantage on placement in tight spaces.      
 
        
        
        
        
            
        Here is an another comparison that shows both speakers on a BDI Octave Media Cabinet, next to a standard size amplifier and turntable in scale:    
    
         Size Comparison image of Polk S20 and Polk TSi100 on a Media Console
        
            Size Comparison image of Polk S20 and Polk TSi100 on a Media Console        
    
Weight Comparison The weight of a loudspeaker can become an important factor if you need to move and reposition the unit often. Weight of a speaker can also "sometimes" be an indicator of the rigidity of the enclosure and the quality of the internal components used. The Polk S20 weighs 7.73kg / 17lbs and the Polk TSi100 weighs 4.53kg / 10lbs. This makes the S20 71% heavier than the TSi100. 
Here is a comparison of how S20 and TSi100's weights compare with the average, max and min weights in Passive Bookshelf class.
    
        Weight
        All Bookshelf Speakers
        
        
        
        
        
     
     
            
        
 What's in the Box of Polk S20? 
        Here are the items that are included inside the box of S20:
        
2 Bookshelf loudspeakers2 Grilles (attached)8 Self-adhesive rubber feetOwners ManualOnline Product Registration        
                
        
 What's in the Box of Polk TSi100? 
        Here are the items that come with the TSi100:
        
2 Black bookshelf speakers Detachable cloth grille (installed) 8 Self-adhesive rubber feet Owner's Manual Wall-Mount template Online registration sheet Polk Audio product brochure        
    
                    
                    
                    
                    
                        
                        
                            
                                                            
                                    |  Max Input Power | 125 watts
                                        vs
                                         100 watts | Handle more power  from your amplifier | 
                                                            
                                    |  Woofer Size | 6.5 inches
                                        vs
                                         5.25 inches | Larger woofer | 
                                                            
                                    |  Low Frequency Response | 39 Hz
                                        vs
                                         61 Hz | Generates deeper bass | 
                                                            
                                    |  High Frequency Response | 40k Hz
                                        vs
                                         24k Hz | Generates higher frequency | 
                                                        
                        
                    
                    
                        
                        
                            
                                                            
                                    |  Sensitivity | 89 dB
                                        vs
                                         88 dB | Play louder with same amount of amplification power | 
                                                            
                                    |  Mounting Bracket | Yes
                                        vs
                                         No | Allows mounting on walls | 
                                                            
                                    |  Height | 279mm
                                        vs
                                         376mm | Easier to fit in smaller spaces | 
                                                            
                                    |  Base Surface Area | 460cm2
                                        vs
                                         756cm2 | Takes less floor space | 
                                                        
                        
                    
                    
                        
			
			
				
					| General | Polk Audio Signature S20 | Polk Audio TSi100 | 
						| Brand | Polk Audio | Polk Audio | 
					
						| Speaker Type | Bookshelf speakers | Bookshelf speakers | 
                                        
                        | Power Range | 20-125 watts | 20-100 watts | 
                    
                    
                                            
                            | Sensitivity | 88 dB | 89 dB | 
                                                                
                            | Impedance | 8 ohms | 8 ohms | 
                    
                    
                    
                        | Frequency Response | 39-40k Hz | 61-24k Hz | 
                    
					
					
					Drivers |  |  | 
                        | Woofer Quantity | 1 | 1 | 
                
                    | Woofer Size | 6.5" | 5.25" | 
                    
                        | Woofer Composition | Mica-reinforced polypropylene | Organic Fiber | 
                                    
                        | Woofer Surround Material | Butyl rubber | Butyl Rubber | 
                
					
                        | Tweeter Size | 1" | 1" | 
                                    
                        | Tweeter Type | Soft-Dome | Dome | 
                
					
					
                    
                        | Aimable Tweeter | No | No | 
					
					
                        | Midrange Driver | No | No | 
                                    
                        | Crossover Frequency | 2500Hz | 2500Hz | 
                
                                    
                        | Firing Direction | rear | rear | 
                
                
					
					Physical Specs |  |  | 
                        | Height | 376.0mm (14.8") | 279.4mm (11") | 
                
                    | Width | 216.0mm (8.5") | 177.8mm (7") | 
                
                    | Depth | 350.0mm (13.8") | 259.0mm (10.2") | 
					
                					
                        | Weight | 7.73kg (17lbs) | 4.53kg (10lbs) | 
                					
                    | Enclosure | Bass Reflex | Bass Reflex | 
                                    
                        | Finish | Meddite MDF | Wood-grain vinyl | 
                
                                    
                        | Available Colors | Black, Walnut, Brown Walnut | Black, Cherry | 
                
                					
                    | Mounting Bracket | No | Keyhole | 
                
                                    
                        | Recommended Stand Height | 24-28" | 16-30" | 
                                                    
                        | Grille | Yes | Yes | 
                					
                        | Moisture Resistancy | No | No | 
                
					Connections |  |  | 
                        | Biamp Inputs | No | No | 
                
                                                                                                                                
                
				Other |  |  | 
                    | Parts Warranty | 5 Years | 5 Years | 
					
					
                    | Labor Warranty | 5 Years | 5 Years |