Buying an Amplifier

 I asked Gemini Deep Research to create a report based on the following prompt:

I’m interested in buying an amplifier for my acoustic guitar. It’s not an electric guitar but it does have the necessary input (it’s a CORT guitar). The amplifier doesn’t need to need to be powerful, it’s only for use in a small room. I’d like a Bluetooth option so that I can listen with earphones if needed. It should  be chargeable via USB C cable but power from the mains is optional. My budget is limited as well so nothing too expensive need be considered.  Can you come up with some options and also consider what cables I need to connect the guitar to the amp. I live in Jakarta so only options available on domestic sites like Tokopedia or Shoppe need be considered.

Here was its response:

\( \textbf{Acoustic Guitar Amplifier Options for Small Room Use in Jakarta}\)

1. \( \textbf{Introduction} \)

This report aims to provide recommendations for acoustic guitar amplifiers suitable for use in a small room in Jakarta, based on the user's specific requirements. The user is interested in purchasing an amplifier for their CORT acoustic guitar, which is equipped with the necessary input jack. The key criteria for the amplifier include suitability for low-volume practice in a small room, Bluetooth connectivity for headphone use, USB-C charging capability (with optional mains power), and affordability, with availability on Indonesian domestic online platforms such as Tokopedia or Shopee being essential.

2. \( \textbf{Understanding Your Requirements} \)

The user has outlined several key requirements for their acoustic guitar amplifier. Firstly, the amplifier should be well-suited for use in a small room. This implies that the power output should be appropriate for intimate settings, allowing for practice and enjoyment without overwhelming the space or causing excessive noise. Amplifiers designed for large venues or high-volume performances are likely unnecessary and may not perform optimally at lower volumes [User Query].

Secondly, Bluetooth connectivity is desired to allow for private practice through earphones. This feature would provide the convenience of silent practice, which can be particularly important in shared living environments or at times when minimizing noise is necessary [User Query]. The ability to connect headphones wirelessly via Bluetooth offers flexibility and ease of use.

Thirdly, the user prefers the amplifier to be chargeable via a USB-C cable, although power from the mains is also acceptable. The preference for USB-C charging suggests a desire for modern connectivity and potentially the convenience of using existing USB-C chargers for various devices. The optional mains power provides flexibility, ensuring that amplifiers without USB-C charging are still considered [User Query].

Fourthly, budget is a significant consideration, and the user is looking for options that are not too expensive. This necessitates focusing on amplifiers that offer a good balance of features and performance within an accessible price range, avoiding high-end or professional-grade equipment [User Query].

Finally, all potential amplifier options must be available for purchase on domestic Indonesian online platforms like Tokopedia or Shopee. This requirement ensures that the user can easily acquire the recommended amplifier without encountering issues related to international shipping, import duties, or availability in the local market [User Query].

3. \( \textbf{Exploring Potential Amplifier Options} \)

Several amplifier models available on Indonesian online marketplaces appear to align with the user's stated needs.

The \( \textbf{Yamaha THR5A} \) is presented as a portable acoustic guitar combo amplifier, optimized for acoustic-electric and silent guitars. It boasts simulations of dynamic and classic tube condenser microphones, along with studio-grade effects, aiming to deliver polished, professional tones in any setting. The amplifier features stereo speakers for external playback from devices like iPods or computers and includes USB connectivity, which facilitates its integration into a studio environment. Furthermore, it can be battery-powered, enhancing its portability. While the THR5A offers features beneficial for acoustic guitarists, the provided information does not explicitly mention Bluetooth connectivity for headphones or USB-C charging. The USB connection seems primarily intended for recording purposes. This amplifier is available on Tokopedia from various sellers, including Sincere Music in Jakarta Pusat, with prices starting around Rp3.010.000. The THR5A is recognized for its suitability for practice, songwriting, and recording, along with its high-quality tone. However, the absence of direct Bluetooth headphone support and USB-C charging might not fully meet the user's specific requirements.

The \( \textbf{Positive Grid Spark Mini}\) is highlighted as a battery-powered portable practice amplifier and Bluetooth speaker with smart app integration. It is designed to produce a "big, beautiful multi-dimensional sound" and is highly portable. Key features include Bluetooth 5.0 wireless connectivity and a USB audio interface that is compatible with most mobile USB-C chargers. The Spark Mini is equipped with a built-in 3,000 mAh rechargeable Lithium battery, offering up to 8 hours of playtime on a single charge with a 3-hour charging time. This amplifier seems to directly address the user's need for Bluetooth headphone use and USB-C charging. It is available on Tokopedia from Nafiri Music Store in North Jakarta with a promotional price of Rp3.608.000 (originally Rp4.100.000). It is also listed on Swee Lee Indonesia for Rp2.750.000. The Spark Mini's strengths lie in its portability, dual functionality as a Bluetooth speaker, and integration with a smart app that provides access to over 100,000 tones, including features like Smart Jam Live and Auto Chords. While Positive Grid markets it for electric, bass, and acoustic guitars , some user feedback suggests that achieving optimal acoustic tones might require adjustments, with opinions on its acoustic performance being mixed.

The \(\textbf{Aroma AG-15A}\) is listed on Tokopedia as a 15W rechargeable acoustic-electric guitar amplifier with USB Type-C charging. It features Bluetooth for playing music from phones or tablets and has two input channels for guitar and microphone. The amplifier is equipped with a 2-band equalizer for the guitar channel and echo control for the microphone input. It also contains a high-quality rechargeable battery. This model directly meets the user's requirements for USB-C charging and Bluetooth connectivity. It is widely available on Tokopedia from various sellers like Brandos (Rp1.159.000) , elevenmusic (Rp1.038.000) , and others. Information from other platforms like eBay and AliExpress  corroborates its 15W power, 5" speaker, Bluetooth, USB charging, and microphone input, often emphasizing its portability and suitability for practice. User reviews suggest positive experiences with its sound quality and portability. 

The \( \textbf{NUX Mighty Lite BT MKII} \) is a 3-watt desktop modeling amplifier that includes Bluetooth connectivity. It features a USB-C port for software communication, audio streaming, and firmware updates. This amplifier offers modeling for electric, bass, and acoustic guitars, along with cabinet IRs and a variety of effects. It can be powered by 6 x AA batteries or a 9V adapter. The Mighty Lite BT MKII is available on Tokopedia from sellers like 3rdaudio (Rp1.350.000)  and tokoaudioprocom (Rp1.392.000). User reviews are generally very positive, highlighting its versatility, sound quality, and affordability.

The \( \textbf{Caline SCURU S8A}\) is a 20W portable mini acoustic guitar amplifier with Bluetooth. It features a Type-C rechargeable built-in battery , an anti-feedback circuit, a microphone input, and a headphone connection. This amplifier appears to meet all the user's requirements. It was available on Shopee from MICKEY MOUSE SHOP in Jakarta Pusat , but is currently sold out. Availability on Tokopedia needs to be checked. User feedback on platforms like YouTube praises it as a "game changer" for acoustic guitar practice, highlighting its portability and sound quality.

 

The \( \textbf{Caline CA200A The Woodsman} \) is a 20W portable mini amplifier for acoustic guitars with Bluetooth connectivity and a Type-C rechargeable built-in battery. It includes multiple effects such as Clean, Reverb, Chorus, and Anti-Feedback. This model also meets all the user's stated requirements. It is available on Shopee from MICKEY MOUSE SHOP in Jakarta Pusat for Rp995.000. User reviews and demos praise its features and suitability for acoustic guitar, with a YouTube demo in Thai also highlighting its Reverb, Chorus, Anti-Feedback, and Bluetooth capabilities.

\( \textbf{Summary: Comparison of Potential Amplifier Options} \)

Parameters: Model | Bluetooth | USB-C Charging | Power Output | Acoustic Guitar Suitability | Estimated Price (Tokopedia/Shopee) | Key Pros | Key Cons |

Yamaha THR5A | No | No | ~10W | Good | ~Rp3.010.000 (Tokopedia) | Portable, good tone, built-in effects | No direct Bluetooth headphone support, no USB-C charging |

Positive Grid Spark Mini | Yes | Yes | 10W | Mixed | ~Rp3.608.000 (Tokopedia), Rp2.750.000 (Swee Lee) | Portable, Bluetooth speaker, smart app integration, USB-C charging | Acoustic tone quality might require tweaking, potentially higher price |

Aroma AG-15A | Yes | Yes | 15W | Good | ~Rp1.034.000 - Rp1.159.000 (Tokopedia) | Affordable, portable, Bluetooth, USB-C charging, mic input | Limited advanced features compared to modeling amps |

NUX Mighty Lite BT MKII | Yes | Yes | 3W | Very Good | ~Rp1.350.000 - Rp1.392.000 (Tokopedia) | Versatile modeling amp, Bluetooth, USB-C audio, portable, positive reviews | Lower power output (3W), might require app for full control |

Caline SCURU S8A | Yes | Yes (Type C) | 20W | Good | Sold out on Shopee (previously available) | Portable, Bluetooth, Type-C charging, anti-feedback, mic input, headphone jack | Currently sold out on Shopee, Tokopedia availability needs to be checked |

Caline CA200A The Woodsman | Yes | Yes (Type C) | 20W | Very Good | Rp995.000 (Shopee) | Very affordable, portable, Bluetooth, Type-C charging, built-in effects | Limited advanced features compared to modeling amps |

4. \( \textbf{Considerations for Small Room Use} \)

The power outputs of the identified amplifiers range from 3W (NUX Mighty Lite BT MKII) to 20W (Caline SCURU S8A and Caline CA200A). These lower wattage amplifiers are generally well-suited for practice in a small room. They can provide sufficient volume for personal enjoyment and practice without becoming excessively loud or causing unwanted distortion that can occur when higher wattage amplifiers are used at very low volumes. As noted in user experiences, even Yamaha THR practice amplifiers, which are in a similar power range, tend to sound better in smaller spaces.

Furthermore, the inclusion of a headphone output, especially when coupled with Bluetooth connectivity, is a significant advantage for small room use. This allows the user to practice silently, which is ideal for avoiding disturbances to others in the vicinity. The Bluetooth feature enhances convenience by eliminating the need for wired headphones [User Query].

5. \( \textbf{Connecting Your Guitar: Cable Recommendations} \)

To connect the user's CORT acoustic guitar (which has an input jack) to any of the recommended amplifiers, a standard 1/4 inch (6.35mm) mono (TS - Tip-Sleeve) instrument cable is required. This type of cable is the standard for connecting guitars to amplifiers and effects pedals.

For home use in a small room, a cable length of around 3 meters (10 feet) is generally recommended. This length should provide sufficient flexibility for movement without being excessively long and potentially causing signal degradation.

Instrument cables are widely available on Indonesian online marketplaces like Tokopedia and Shopee. The user can search using terms such as "kabel gitar" , "kabel instrument" , or "jack gitar." Various brands, including Ernie Ball, Fender, Vox, and Klotz, offer instrument cables. While factors like shielding quality and connector type (straight or right-angle) can influence the cable's performance and durability, a standard, reasonably priced instrument cable should be adequate for the user's needs in a home practice setting. The choice between a straight or right-angle connector might depend on the location and orientation of the input jack on the user's CORT guitar.

6. \( \textbf{Budgetary Awareness} \)

Considering the user's limited budget, the Aroma AG-15A and the Caline CA200A The Woodsman appear to be the most budget-friendly options identified on Tokopedia and Shopee in Jakarta, with prices around or below Rp1.160.000 and Rp995.000 respectively. The NUX Mighty Lite BT MKII, priced around Rp1.350.000 on Tokopedia , is also a strong contender within a potentially limited budget.

The Positive Grid Spark Mini, while offering a comprehensive set of features, might be slightly more expensive, with listings around Rp3.608.000 on Tokopedia, although a lower price of Rp2.750.000 was found on Swee Lee Indonesia. The Yamaha THR5A seems to be the most expensive among the considered options, priced around Rp3.010.000 on Tokopedia.

It is advisable for the user to compare the current prices and availability of these models across different sellers on Tokopedia and Shopee to secure the best possible deal that fits their budget.

7. \( \textbf{Conclusion and Recommendations} \)

Based on the analysis of the user's requirements and the available amplifier options on Indonesian domestic online platforms, several models stand out as potential choices. The Aroma AG-15A and the Caline CA200A The Woodsman are particularly compelling due to their affordability, direct fulfillment of the key requirements (small room suitability, Bluetooth for headphones, USB-C charging), and local availability on Tokopedia and Shopee.

The NUX Mighty Lite BT MKII also presents a very strong option with its versatile amp modeling, including acoustic simulations, Bluetooth, USB-C connectivity, and positive user feedback, all within a reasonable price range.

While the Positive Grid Spark Mini meets the Bluetooth and USB-C charging criteria and offers numerous features, it might be slightly more expensive, and user opinions on its acoustic tone quality are somewhat varied. The Yamaha THR5A, although a well-regarded amplifier for acoustic guitars, lacks direct Bluetooth headphone support and USB-C charging, making it a less ideal fit for the user's specific needs.

Therefore, it is recommended that the user prioritize checking the current prices and availability of the Aroma AG-15A, Caline CA200A The Woodsman, and NUX Mighty Lite BT MKII on Tokopedia and Shopee. Purchasing a standard 1/4 inch TS instrument cable with a length of approximately 3 meters from either of these platforms will be necessary to connect the guitar to the chosen amplifier. The Caline CA200A The Woodsman, with its very attractive price point on Shopee, appears to be a particularly strong recommendation for a budget-conscious user seeking all the required features.

My Ailing Laptop

Lately, my late 2013 MacBook Pro is refusing to stay connected to the household WiFi which is a source of irritation. It had been flaky for a while and one might suspect the laptop's WiFI but it connects just fine to the WiFi from my iPhone when I use the latter as a hotspot. I'm currently running a ten metre cable from the household router to it so all is well. I don't move about much with it anyway so it's not really an issue.

It's back to the old pre-WiFi days
for me as my laptop lapses into senility

Ever since I installed Linux Mint on my laptop to replace the Mac OS, the Bluetooth has not worked but that didn't bother me. I replaced the ten year old battery with a new one when I was in Australia earlier this year and that has really given the old laptop a new lease on life. There's no doubt however, that the device, like its owner, is showing its age. Last night, I discovered that closing the lid placed the laptop in permanent suspension from which it would not awake. Once the lid closed, I needed to restart it. However, by changing preferences so that closing the lid had no effect, I was able to remedy that little glitch.

I've lately found my misplaced USB cooling pad and so I now rest the laptop on that to keep it cool as it can often overheat if placed under even minimal stress. Overall, despite its current quirks, the machine is quite sufficient for my needs and I've grown quite attached to it after using it regularly for over nine years now. It may even see me out. Who knows? In the meantime I still have my Raspberry Pi 400 keyboard computer as a back up in case my primary device has a heart attack. 

My backup device
Raspberry Pi 400

There is a Raspberry 5 out now but no sign of a Raspberry Pi 500 as yet. Regardless, such a device would be superfluous to my needs at the moment. As the year draws to a close, I must note that my output this year of 26 posts falls far short of my output for 2022 when I made 47 posts. However, it's consistent with my output in other years since my output for earlier years was:

►  2021 (27)

►  2020 (22)

►  2019 (17)

►  2018 (16)

►  2017 (24)

►  2016 (16)

The average number of posts for the years 2016 to 2023 is a little over 24 posts or almost exactly two per month.

Chromium Problems on Raspberry Pi OS After Update

After updating my Raspberry Pi OS on my Raspberry Pi 4, I now find that YouTube and YouTubeMusic on Chromium both cause the browser to crash. The Chromium browser is a far cry from the Chrome browser. The former has multiple deficiencies and this latest disaster is further proof of this. Firefox has no such problems so I have been using that browser to launch both programs.

The solution however, proved simple enough following a recommendation from an online forum. Simply reinstall Chromium! A logical enough first step in troubleshooting software problems. Overall the Raspberry Pi 4 that I bought earlier in the year is working well enough for what I need to do. I recently purchases an M1 MacBook Pro 14" for my granddaughter who needed a computer for her University studies. I'd much prefer to be using that of course.

Such a computer does not come cheap however, and in terms of value for money, the Pi wins hands down. The Bluetooth still doesn't work but I have my wired earbuds working despite the inexplicable lack of a direct earphone jack (see earlier post).

Sound Problems Solved for Raspberry Pi 4000

After some hours trying a variety of suggested solutions to the Raspberry Pi 400's Bluetooth woes, I finally managed to achieve audio output from the device. Unlike the traditional Raspberry Pi, the 400 does not have an audio jack for reasons known only to the manufacturer of the device. This presented a problem for me because my monitor had no speakers so the HDMI cable had nowhere to send the audio output. 

I had a hub with a variety of ports, including a headphone jack. It could only be connected to a computer or other device via USB C. My 2013 MacBook Pro did not have a USB C port but I recently bought a USB 3 to USB C converter. My Mac had a headphone jack and so I had been using that. However, I tested out the jack on the hub and it worked fine. I then plugged the hub into the 400 via the USB C port but there was no audio out. However, using the USB 3 to USB C converter and plugging to hub into that (as I'd done on my laptop), I finally had audio out.

The Bluetooth problem was never solved and probably never will be but I'm happy to finally have sound on my Raspberry Pi 400, even if it require a converter and hub which I fortunately had at hand. 

Testing Out The Raspberry Pi 400

 

Figure 1

Figure 1 shows the ports on my newly acquired Raspberry Pi 400 with the following specifications:

• Broadcom BCM2711 quad-core Cortex-A72 (ARM v8) 64-bit SoC @ 1.8GHz
• 4GB LPDDR4-3200
• Dual-band (2.4GHz and 5.0GHz) IEEE 802.11b/g/n/ac wireless LAN
• Bluetooth 5.0, BLE
• Gigabit Ethernet
• 2 × USB 3.0 and 1 × USB 2.0 ports
• Horizontal 40-pin GPIO header
• 2 × micro HDMI ports (supports up to 4Kp60)
• H.265 (4Kp60 decode); H.264 (1080p60 decode, 1080p30 encode); OpenGL ES 3.1, Vulkan 1.0
• MicroSD card slot for operating system and data storage
• 78- or 79-key compact keyboard (depending on regional variant)
• 5V DC via USB connector
• Operating temperature: 0°C to +50°C ambient
• Maximum dimensions 286 mm × 122 mm × 23 mm

Figure 2 shows its actual appearance.

Figure 2

I bought it on a whim for my 73rd birthday and it only arrived today. The operating system was already installed on the 16GB memory card and, after connecting the power and the monitor, I was up and running in no time. The first hardware issue that I encountered was with Bluetooth. My ancient monitor has no inbuilt speakers and so I assumed that I would be able to listen to sound using my Bluetooth earbuds. Not so. The Raspberry Pi's Bluetooth 5.0 did not detect them.

I've only ever used the earbuds with my iPhone and they work flawlessly on that device. I succeeded in connecting to them from my Ubuntu laptop and the connection was terrible but it was still, technically, a connection. With a second set of Bluetooth earbuds, I encountered the same problem. I'll come up with a solution to this Bluetooth "invisibility" sooner or later probably, after all it's only Day 1. I know what I'm letting myself in for. If I didn't want any problems, I'd simply go out and buy a Mac of some description. I still may do so but for the moment I'll enjoy tinkering and troubleshooting with my new toy.

Software-wise, it becomes clear that the Chromium browser and the Chrome browser as two different beasts as the following extract from this site explains:

Google Chrome is one of the most popular browsers all over the world. And Raspberry Pi is the most popular mini-PC device. But unfortunately, they can’t meet together –  there is no Chrome build for Raspberry Pi (and for any other ARM-based PC except Chromebook). You can use a number of other browsers (such as Epiphany, IceWeasel or even Lynx), but will face a lack of functionality.  Many Pi-world enthusiasts use the open source version of Chrome – Chromium browser. But this isn’t a full replacement.

Chrome includes a number of proprietary libraries and in some cases, you need to use authentic Google software. For example, you can watch videos on Netflix or Amazon Prime with Chrome and can’t with Chromium. Good news that there is a simple solution to override this issue. Using Exagear Desktop allows you to get full x86 Linux environment. And this means that you can launch any application available in x86 Linux world, including Google Chrome!

Maybe I'll try Exagear out at some point but at the moment I have 4GB of RAM and a 16GB memory card as permanent storage. I need to be careful not to overtax these limitations. If possible, I'd like to upgrade to 8GB RAM and swap the memory  card for a fast SSD. I need to watch some tutorials on the subject to determine if this is possible.

ADDENDUM:

I'll quote from the article on this website:

Updating the firmware is as important as keeping your operating system and software up to date, though there might be less frequent stable updates. The main importance of this is security patches. If vulnerability in the code has been found, your Raspberry Pi firmware needs to be updated to reduce the risk of it being exploited.

The other reason is performance enhancement. Though updates usually only bring minor changes, some offer major benefits. For example, the Raspberry Pi Foundation’s November 2021 update increased the turbo-mode clock from 1.5 GHz to the 1.8 GHz for recent Raspberry Pi 4s.

If you’re running Raspberry Pi OS, your firmware options are limited to what’s offered by the Raspberry Pi Foundation. We’ll mention some alternative Raspberry Pi-compatible operating systems later.

The Raspberry Pi Foundation has put a lot of work into making the initial setup and update process for Raspberry Pi OS extremely easy. It’s detailed on their website, but the basic steps are to check for updates with sudo apt update followed by running a full upgrade (if there’s anything new) with sudo apt full-upgrade. Using this process, you’ll be updating the operating system as well as the firmware to the latest stable releases.

My hope of course was that this update would solve my Bluetooth problems. As if it would be that easy! The update made no difference whatever in that department. 

USB Tethering: Mac and Android

I long ago discovered that my Macbook Pro doesn't play well with repeaters. It will connect without problem to the main router but, if it needs to connect via a repeater, then IP address conflicts arise and connectivity is lost. This was the problem in my bedroom but I overcame it by making use of the Ethernet port on my repeater. Once I connected the laptop to the repeater via an Ethernet cable, there was no problem. 

Recently however, my granddaughter was having buffering problems when watching Netflix over WiFi on her iPad Pro. I gave the repeater to her, connected her to an Ethernet cable via a hub and all was well. For her, that is, not for me. I was very quickly confronted with my old problem again. However, I had my Android phone and thought that the solution would be to tether the laptop to my phone via Bluetooth. The Macbook was having none of that. No problem I thought. I have a USB cable so I'll tether via that. No luck.

A little investigation led me to a site run by Joshua White and an app called HoRNDIS-9.2.pkg (46919 bytes) that I downloaded to my laptop and installed. I restarted my laptop and connected to my phone via USB and I'm typing happily away creating this post. 

No help of course from Apple popped up at the top of the search results but at least I'm connected now. I haven't tried watching Netflix or similar yet, in order to test the speed of the connection. I'll do that later and add to this post if there any problems. On his website, Joshua explains the technicalities of how the app works.

I still don't know why the bluetooth tethering didn't work. Perhaps there's a similar program that needs to be downloaded for that to work as well. For the moment, I'm just happy that I'm connected. Perhaps the motto of all this is indeed that CABLE IS STABLE.