Comparison Sony Extra Bass SRS-XB31 vs Sony SRS-X33

— Bluetooth. Wireless technology for transmitting sound from mobile phones, tablets, etc. Allows you to connect a device wirelessly at a short distance from the signal source. The quality and overall capabilities of Bluetooth vary depending on the version:

Bluetooth 4. Each version brings improvements relative to the previous one. So in version 4.0, three standards were actually combined: traditional Bluetooth, a high-speed channel and an energy-saving mode for small amounts of data. This allowed us to optimize channel usage and battery consumption. In version 4.1. Noise immunity has been enhanced when working next to 4G LTE modules. And version 4.2 introduced mainly general improvements in speed and security.

Bluetooth 5.0. One of the most important innovations of the Bluetooth 5.0 standard is the expansion of the capabilities of the BLE (Bluetooth Low Energy) mode: if necessary, the device can increase the range by reducing the speed, or speed up transmission by reducing the range. In addition, a number of improvements have been introduced regarding simultaneous work with multiple connected devices.

- Bluetooth 5.1. A significant upgrade in version 5.1 was the ability to accurately position the signal transmitter (receiver). If previous versions could only determine distance, then version 5.1 can also determin...e direction. Thus, navigation began to function better and more accurately, which improved work with the smart home system, searching for connected devices, etc. In addition to this, the improvements again concerned saving energy consumption and simultaneous work with several connected devices.

- Bluetooth 5.2. The next update, after 5.1, is Bluetooth 5th generation. The main innovations in this version are a number of security improvements, additional optimization of power consumption in LE mode and a new audio signal format for synchronizing parallel playback on multiple devices.

— Bluetooth 5.3 The Bluetooth v 5.3 wireless communication protocol was introduced at the dawn of 2022. Among the innovations in it, they accelerated the process of negotiating a communication channel between the controller and the device, implemented the function of quickly switching between the operating state in a low duty cycle and a high-speed mode, and improved the throughput and stability of the connection by reducing susceptibility to interference. When unexpected interference occurs in Low Energy mode, the procedure for selecting a communication channel to switch from now on has been accelerated. There are no fundamental innovations in protocol 5.3, but a number of qualitative improvements are evident in it.

- Bluetooth 5.4. The version was presented at the beginning of 2023, the range and data exchange speed were increased. Also in Bluetooth v 5.4, the energy-saving BLE mode has been improved. This protocol uses new security features to protect data from unauthorized access, has increased connection reliability by selecting the best channel for communication, and prevents connection losses due to interference.

—Mini-Jack (3.5 mm). Standard Aux audio input for connecting speakers to an audio source, such as a laptop or smartphone.

- USB. The presence of a USB connector allows you to connect a flash drive, mobile phones, MP3 players and other similar peripherals to the portable speakers. Accordingly, such models have a built-in player and allow you to use connected gadgets exclusively as a drive.

- Card reader. Like the USB described above, this item implies the presence of a built-in player in the acoustics. And the card reader allows you to use memory cards as a drive on which songs will be recorded.

— FM receiver. A built-in tuner allows the speaker system to work as a full-fledged FM radio receiver - this is the range that is popular among music radio stations (in particular, due to the ability to broadcast sound in stereo format).

The total power of all channels of the speaker system. The higher the power, the larger the size of the room in which the audio system can be used, however, more powerful portable speakers usually have larger dimensions and weight.

The model supports the ability to synchronize the operation of several speakers connected to one signal source. This solution allows you to realize truly stereo sound, improve the quality and power of sound reproduction, and also expand the stereo panorama. The only thing is that both speakers must support the appropriate connection type. Different brands may have their own technologies for combining speakers (JBL Connect, JBL PartyBoost, Sony Party Chain), or maybe a universal TWS.

Initially, sound transmission via Bluetooth involves quite strong signal compression, which can greatly spoil the experience when listening to music. To eliminate this drawback, various technologies are used (the most popular of which is the aptX codec). Of course, to use any of the technologies, it must be supported not only by the sound system, but also by the Bluetooth device with which it is used.

- aptX. A Bluetooth codec designed to significantly improve the quality of audio transmitted over Bluetooth. According to the creators, it allows you to achieve quality comparable to Audio CD (16-bit/44.1kHz). The benefits of aptX are most noticeable when listening to high-quality content, but even on regular MP3 it can provide a noticeable sound improvement.

- aptX HD. This codec is a further development and improvement of the original aptX technology, allowing you to transmit sound in even higher quality - Hi-Res (24-bit/48kHz). According to the creators, this standard allows you to achieve signal quality superior to AudioCD and sound purity comparable to wired communication. The latter is often questionable, but it can be argued that overall aptX HD provides very high sound quality. On the other hand, all the advantages of this technology become noticeable only on Hi-Res audio - with quality 24-bit/48kHz or higher; otherwise, the quality is limited not so much by the characteristics of the connection as by the propertie...s of the source files.

- aptX Low Latency. A specific version of aptX described above, designed not so much to improve sound quality, but to reduce delays in signal transmission. Such delays inevitably occur when working via Bluetooth; They are not critical for listening to music, but when watching videos or playing games, there may be a noticeable desynchronization between the image and sound. The aptX LL codec eliminates this phenomenon, reducing latency to 32 ms - such a difference is imperceptible to human perception (although for serious tasks like studio audio work it is still too high).

- A.A.C. A codec used primarily in Apple portable devices to improve sound transmitted via Bluetooth. In this sense, it is similar to aptX (see the corresponding paragraphs), but is noticeably inferior to it in terms of capabilities: if the sound of aptX is compared with Audio CD, then AAC is at the level of an average quality MP3 file. However, for listening to the same MP3s, this is quite enough; the difference becomes noticeable only on more advanced formats.

-LDAC. Sony's proprietary Bluetooth codec. It surpasses even aptX HD in terms of bandwidth and potential sound quality, providing performance at the Hi-Res level of 24-bit/96kHz audio; there is even an opinion that this is the maximum quality that it makes sense to provide in wireless headphones - further improvement will be simply imperceptible to the human ear.

— Microphone for speakerphone. The ability to use portable speakers as a speakerphone system for conversations on a paired mobile phone. In this mode, the speakers connect to the device via Bluetooth, and the speech is transmitted to the interlocutor using the built-in microphone. The voice of the subscriber on the other end of the line is output not to the speaker of the phone, but directly through the speakers of the speaker system. This is often much more convenient than holding the phone close to the ear, or in situations when your hands are busy. In addition, speakerphone can be very useful if several people need to participate in the conversation.

— NFC chip. NFC is a short-range wireless communication technology (about 10 cm). It allows for many different uses, but in portable speakers it is usually used as an addition to Bluetooth, making it easier to set up a communication. For example, a smartphone with an NFC module can simply be brought to a speaker with the same function — and both devices will automatically recognize each other, and the user will only need to confirm the communication.

— Multipoint. The technology used in Bluetooth models allows the speaker to connect to several devices simultaneously. Thanks to this, you can, for example, listen to music from a laptop, and when a call comes in on your mobile phone, switch the speakers to a c...onversation. Different manufacturers have their own features of this technology, and therefore, if the multipoint function is critical for you, you should separately clarify the details of its operation in the selected model.

— Bass Boost. A function that provides amplification of low frequencies — for powerful and rich bass. Often implemented as a single button, with which you can actually "turn the bass on and off." Bass Boost is more convenient than adjusting low frequencies using an equalizer; in addition, various special technologies can be used to enhance bass.

— Mobile application. The ability to operate the functions and settings of portable sound system through a mobile application for a smartphone or tablet. The device usually communicates with gadgets via the Bluetooth wireless protocol. The proprietary software may include tools for flexible sound adjustment (equalizer, bass boost, etc.), wireless communication management, sound source selection, etc. Also, the ability to update the firmware of portable sound system is often implemented through a mobile application.

— Light effects. Such effects can be different — from the simplest set of lights flashing at a constant frequency to advanced color music systems that produce multi-colored patterns in time with the music being played. In any case, this function has more of an entertaining meaning and does not affect the sound of the device in any way.

Operating time of a portable audio system without connecting to an external power source (network or USB port, depending on the capabilities). Note that manufacturers tend to indicate battery life in their specifications under optimal conditions for energy saving: at low volume, without using additional functions, etc. Therefore, in fact, this indicator may be noticeably lower than the claimed one, and speakers with a long operating time will not sound at full volume for the specified hours.

Ability to work portable acoustics in power bank mode. This mode is only found in models with their own batteries (see "Power type"): it allows you to use this battery to power a smartphone or other external gadget. Thus, acoustics can play the role of an additional external battery, which is important in situations where it is not possible to charge a portable device in time.

Note that Power Bank speakers may only be compatible with certain phone models; this point should be clarified before buying.

The presence in the design of the acoustics of a protected housing that prevents dust and moisture from entering the sensitive electronic filling. The specific degree of such protection in different models may be different — some speakers are able to endure even complete immersion under water ( waterproof), others are designed only for exposure to moderate rain. Therefore, the specifics of the protected case should be clarified separately according to the manufacturer's official data. However, anyway, such speakers will be more resistant to bad weather and better suited for outdoor use than those that do not have dust and water protection; therefore, if you are choosing acoustics for outdoor trips, it makes sense to pay attention to models with this function.

Some models with this feature are officially IP certified. The IP index includes two digits — for example, IP54. The first digit indicates the degree of protection against dust, the second — from moisture; the higher the number, the higher the corresponding degree of protection, detailed data can be found in special sources.