Combos

A quick note on power:
Don’t be blinded by the wattage numbers: these are often highlighted without specifying the type of watt (Watt RMS, Watt AES, musical Watt, max Watt, clean Watt…). Additionally, it's essential to understand that the acoustic power / sound pressure produced by a combo depends not only on the electrical power (Watt RMS) delivered by its amp head, but also, and very significantly, on the efficiency (sensitivity) of the speaker(s) used. For example, if we compare two combos from Guitar Sound Systems: GSS' 05G200 50W rms mini combo using a small 5" (13cm) speaker with an efficiency rated 90-91dB for 1W at 1m, it will provide a maximum sound pressure 6dB lower than GSS' Vintage Clean Master combo, which has 45W RMS output power and is loaded with a 12" (31cm) speaker with an efficiency of 97dB. As a result, despite having very similar electrical power (50W and 45W), GSS' Vintage Clean Master will produce 4x the acoustic power of GSS' 05G200 (Every 3dB increase in speaker efficiency represents a doubling in acoustic power).

GSS “Nomadic” mini amps:
They are all equipped with small 5" (13cm) speakers and amp heads that provide two 50W RMS outputs. But what are the differences between the different GSS 05G200xxx models?

The 05G200 is the "base" model with a Celestion 5" (13cm) speaker that has a very flat response, neutral, and high definition sound. It has two channels: a clean channel and a channel where one can adjust the gain for saturated sounds.

The 05G200SJC Jazz Cat only has a single channel for clean sounds but includes bass/mid/treble controls and a line-out. These are its only differences from the 05G200, with which it shares the same amplification electronics and the same Celestion speaker. Its “Jazz Cat” name comes from its popularity with hollow-body guitar players, for which the speaker's limited bass response - due to its small size - is not necessarily a disadvantage, especially when used for jazz with Archtop guitars, but also with any electro-acoustic guitar.

The “colored” versions —05G200SM, 05G200SW, 05G200SG, and 05G200SB— are identical to the 05G200 base model except for the color of their aluminium grid and control knobs, and the use of a 5" (13cm) Sica-Jensen speaker instead of Celestion. This speaker has a slightly less neutral sound, with a more scooped midrange and slightly “bluesier” tones.

For applications requiring more acoustic power, especially when using a mini combo in a brass band or any street band with many brass instruments, a 100W model equipped with two 5" (13cm) speakers is recommended: either the 25G200 , which has two completely separate cabinets, or the 25G200SLP model, where the two cabinets are joined and mounted one above the other, making it easy to carry the unit with a simple guitar strap.

The special case of the GSS Krazy Cat mini combo:
This model is designed as a “Jazz Cat” supercharged with steroids. The main difference from the Jazz Cat is the use of a high-efficiency 5" (13cm) Sica-Jensen speaker with a neodymium magnet, housed in a slightly larger cabinet. The increased efficiency of this speaker compared to the Jazz Cat provides it with an additional 3dB maximum sound pressure, effectively doubling its acoustic power. The frequency response of this speaker is still very limited in the low end (you can’t work miracles with a 13cm speaker, especially when it’s highly efficient), and its overall response is slightly less neutral than the Jazz Cat's, with a tone closer to what you’d expect from a classic 10" or 12" guitar speaker, including very clear and slightly forward highs. The GSS Krazy Cat mini combo is thus suited for a wider range of musical styles than the Jazz Cat.

The GSS Master LB combo:
This model is designed as a "Swiss Army knife" in a "lunchbox" format. Larger than the GSS 05G200 / Jazz Cat / Krazy Cat, but more compact than a classic 10-12" combo, it integrates a wide range of features: two channels (clean and distorted), built-in reverb, tone control, headphone jack, and DI output.

The GSS 08GA70 Acoustic Dog compact acoustic combo:
This is an ultra-compact amplification solution for electro-acoustic guitars, equipped with the same 8" (20cm) dual-cone speaker used in previous revision AER Compact60 combos (which used two per amp in a larger, heavier box). This combo is designed for extreme simplicity with excellent sound quality.

Finally, GSS offers two guitar combo products with 12" (31cm) speakers and hybrid amp heads (tube preamp and transistor power stage) producing a very warm and crystal clear sound in a compact and lightweight format:
Both models share the same amp head electronics in 45W and 80W RMS versions. The use of tubes for preamplification and transistors for power stage allows for significant weight and size reduction compared to a full-tube amp head. Maintenance and reliability are also greatly improved, as the small preamp tubes last about 10 times longer than power tubes, which need to be replaced regularly and can cause expensive breakdowns when they reach the end of their life.

The GSS 45W Vintage Clean Master combo is built with a handmade poplar cabinet in our Toulouse workshop and it is loaded with a Celestion Creamback neodymium speaker, resulting in very low weight and a very compact size.

Its big brother, the GSS 80W Heavy Blues Master, is built with a reinforced 3-ply spruce cabinet, entirely handmade in our workshop, and it features a speaker with a very large ferrite magnet, achieving a 100dB efficiency. It is characterized by a very dynamic and detailed rich response, enhancing the articulation of the low and high frequencies compared to the Vintage Clean Master.