--- product_id: 94770582 title: "B4-X Portable Dual-Mono Vacuum Tube Headphone Amplifier; Mini Balanced Audio Headphone Amp B4 Upgrade Version" brand: "little bear" price: "543505CFA" currency: XOF in_stock: true reviews_count: 4 url: https://www.desertcart.sn/products/94770582-b4-x-portable-dual-mono-vacuum-tube-headphone-amplifier-mini store_origin: SN region: Senegal --- # 300Ξ© headphone support Dual-mono balanced Rechargeable battery B4-X Portable Dual-Mono Vacuum Tube Headphone Amplifier; Mini Balanced Audio Headphone Amp B4 Upgrade Version **Brand:** little bear **Price:** 543505CFA **Availability:** βœ… In Stock ## Summary > 🎢 Elevate Your Sound Game with the Little Bear B4-X! ## Quick Answers - **What is this?** B4-X Portable Dual-Mono Vacuum Tube Headphone Amplifier; Mini Balanced Audio Headphone Amp B4 Upgrade Version by little bear - **How much does it cost?** 543505CFA with free shipping - **Is it available?** Yes, in stock and ready to ship - **Where can I buy it?** [www.desertcart.sn](https://www.desertcart.sn/products/94770582-b4-x-portable-dual-mono-vacuum-tube-headphone-amplifier-mini) ## Best For - little bear enthusiasts ## Why This Product - Trusted little bear brand quality - Free international shipping included - Worldwide delivery with tracking - 15-day hassle-free returns ## Key Features - β€’ **Premium Build Quality:** Crafted with gold-plated sockets and high-end components for superior durability. - β€’ **Versatile Connectivity:** Compatible with both 3.5mm and 2.5mm outputs for all your headphone needs. - β€’ **Portable HiFi Experience:** Take your music anywhere with a compact design that fits in your hand. - β€’ **Smart Battery Management:** Enjoy uninterrupted listening with built-in battery protection and automatic shut-off. - β€’ **Unmatched Sound Separation:** Experience audio like never before with independent amplification for each channel. ## Overview The Little Bear B4-X Portable Dual-Mono Vacuum Tube Headphone Amplifier is a high-performance audio device designed for audiophiles on the go. Featuring independent amplification for enhanced sound separation, a compact design for portability, and compatibility with various headphone outputs, this amplifier ensures a premium listening experience. With its high-quality materials and smart battery management, the B4-X is perfect for those who demand both quality and convenience in their audio gear. ## Description ## Technical Specifications | Specification | Value | |---------------|-------| | Material | Gold-plated | | Lithium Battery Weight | 32.6 Grams | | Item Dimensions L x W | 4.5"L x 2.7"W | | Color | Upgrade Version Black | | Includes Rechargeable Battery | Yes | | Lithium Battery Voltage | 12 Volts | | Battery Cell Composition | Lithium | | Battery Description | Lithium | | Power Source | Battery Powered | | Special Features | Portable | ## Product Details - **Brand:** Little Bear - **Color:** Black - **Material:** Gold-plated - **Model Name:** Little Bear B4-X - **Power Source:** Battery Powered ## Images ![B4-X Portable Dual-Mono Vacuum Tube Headphone Amplifier; Mini Balanced Audio Headphone Amp B4 Upgrade Version - Image 1](https://m.media-amazon.com/images/I/71NgP4S28HL.jpg) ## Questions & Answers **Q: Why mine which is brand new stopped working and makes a loud hissing/banging noise?** A: Charge it. It’s just outta power **Q: Does this B4-X works while charging? without any limiter like "for safety reason"** A: Hello. Sorry B4-X still has the limitation. **Q: best place to buy op amps** A: Amazon. **Q: Mine stopped holding a charge, can the batteries be replaced?** A: Yes you can, easy todo ## Customer Reviews ### ⭐⭐⭐⭐⭐ A portable tube headphone amp.....Little Bear B4-X is quite good. *by A***E on April 22, 2020* I bought this amp 4 months ago more because It was a unique idea. Portable tube headphone amps are something that I didn't think existed and if they did they would be at least much more monetarily.I have not upgraded the opamp yet to the Burson Audio which was suggested by another buyer but it really stands by itself as it is as a great audio product.The fit of the audio cable is important from the source to the amp but they provided a pretty nice beefy short cable with the amp.So far using a Pioneer Hires player, Sony AW55, and even my LG V40 thinq in Airplane mode with its 4 DACS and very good audio section the B4-X was solid amp quiet and works well with offboard DACS as well.Having been a musician for many years and also a Progressive Trance DJ I have put it through its paces with my BeyerDynamic Dt1350s, Tesla T1, Focals, and IEMS from my Westone 4Rs to 5 Driver IEMs. It provides solid power to drive up to 300 ohm over the ears without an issue. Pair it with a good outboard DAC and it is really a great unit.For 99$ it punches WAY ABOVE its class. It was so good I bought a second one and sent it to my Brother so he could use it with his Audeze and Hifiman Planers.I look forward to swapping out the OPAMP to see the levels that I can drive it to.In a world of expensive electronics that don't deliver the Little Bear B4-X is really a steal.What started out as a "OKAY was looking at a Schitt Valhalla to listen at home but a Portable tube headphone amp!!!????? I gotta give it a whirl" turned into a great little tubeamp which is much better than the price or printing on the case shows. ### ⭐⭐⭐⭐⭐ Great... until it didn't work after only 11 uses... but the company made it right. *by J***F on January 4, 2019* I received the Little Bear B4-X and was extremely satisfied... for the first 16 days. During that time I used it a total of 11 times, adding up to 30 hours of listening time. I was keeping careful track of the number of hours and paying attention to how the unit's sound would change after a "burn-in" of 100 hours. The shortest listening session was 1 hour and the longest 5 hours. As I said, I was extremely satisfied and the sound was great. The fact it wouldn't run with passive power/while charging was only a minor annoyance and I was more than happy to just use it when charged... until yesterday, when after a listening session it simply wouldn't charge at all. After using it and plugging it in to charge the charger is no longer showing a continuous red light while charging, but instead blinking red/yellow. I thought maybe it was normal because it had been the longest listening session I did, totaling 5 hours so I left it charging overnight and the behavior never changed. When I tried to use it today it won't power up at all and when plugged in again it is still blinking red/yellow. As it also doesn't work while plugged in I am now left with a useless paperweight and major disappointment. If the company, seller, or Amazon makes it right I will update this review accordingly....and so I am. I was contacted by the company, who stated they believed it was an issue with the charger & not the LittleBear, asking if I could test it with a different power supply; I didn't have a suitable one at home, so went to a battery store and attempted to charge with a demo unit of a multi-voltage charger, set to the right settings. Still no charging. As soon as I relayed this info they informed me they were sending me a new unit, which arrived in record time and was again working flawlessly - but I was hesitant to immediately update this review, as the issue with the first unit showed up during "stress testing" as I was "burning in" the unit. Proceeded to burn-in the unit for a full 100h and have listened for another hundred or so since. The new Little Bear is performing admirably and sounds even better after the burn-in. Completely satisfied with the product and their customer service. ### ⭐⭐⭐ Fun, noisy little amp. *by N***E on February 19, 2023* The noise floor is terrible, let's just get that out of the way. Can't notice it when a song is playing, but it is prominent during pauses.Despite that, it colors audio in a pleasant way. I really enjoy it when I'm in the mood for it. Lots of high-end sparkle.It travels fairly well, but I dislike the proprietary charger.I tried the band stack thing, don't recommend it. It gets warm, and looks like something that would get you flagged and tackled by tsa agents. Oh, and it's heavy when you stack it with a dap.It's nice to have the portable tube amp option, I enjoy it for the novelty. ## Frequently Bought Together - Little Bear B4-X Portable Dual-Mono Vacuum Tube Headphone Amplifier; Mini Balanced Audio Headphone Amp B4 Upgrade Version - Sennheiser HD 600 - Audiophile Hi-Res Open Back Dynamic Headphone - Qudelix-5K Bluetooth USB DAC AMP with LDAC, aptX Adaptive, aptX HD, AAC (Dual ES9219 3.5mm Unbalanced & 2.5mm Balanced Output) --- ## Why Shop on Desertcart? - πŸ›’ **Trusted by 1.3+ Million Shoppers** β€” Serving international shoppers since 2016 - 🌍 **Shop Globally** β€” Access 737+ million products across 21 categories - πŸ’° **No Hidden Fees** β€” All customs, duties, and taxes included in the price - πŸ”„ **15-Day Free Returns** β€” Hassle-free returns (30 days for PRO members) - πŸ”’ **Secure Payments** β€” Trusted payment options with buyer protection - ⭐ **TrustPilot Rated 4.5/5** β€” Based on 8,000+ happy customer reviews **Shop now:** [https://www.desertcart.sn/products/94770582-b4-x-portable-dual-mono-vacuum-tube-headphone-amplifier-mini](https://www.desertcart.sn/products/94770582-b4-x-portable-dual-mono-vacuum-tube-headphone-amplifier-mini) --- *Product available on Desertcart Senegal* *Store origin: SN* *Last updated: 2026-07-17*