Gear Review: Glockenklang Blue Soul

THE WORD GLOCKENKLANG MEANS “bell sound” in German, and the company bearing that name seems intent on making sure nothing gets lost in translation.
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THE WORD GLOCKENKLANG MEANS “bell sound” in German, and the company bearing that name seems intent on making sure nothing gets lost in translation. It is rare in this price-point obsessed world to find companies still willing to build an uncompromising product regardless of the cost, but the folks at Glockenklang have been doing it that way for years. Their sonically pure rigs have become a benchmark in the high-end amp market, and while their level of quality does not come cheaply, the old adage “you get what you pay for” applies here. The Blue Soul amp is Glockenklang’s first offering in the digital Class D realm, and they have packed it full of features, but does it perform to the standard set by its vaunted predecessors?

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The Blue Soul has two inputs; Input A is set at 3MΩ and is suitable for passive or active basses, while Input B has an impedance of 4.7MΩ and its own pre-gain trim control that will pad down to -20dB for high-output instruments and piezo pickups. The inputs can be switched via the front panel. The TUNE button mutes the audio signal except to the dedicated tuner out, and can also be footswitch activated. The powerful EQ section can be completely bypassed with the EQ switch. The parallel effects loop is post-EQ and is activated via the front panel switch (or footswitch), and has separate gain and mix controls on the faceplate to tailor the ideal signal level to your pedalboard. The effects loop can also be used as an mp3, or external audio source input for playing along to tracks or drum machines. The master volume control also applies to the ¼" headphone out on the back panel, and is designed to provide full power set at 3 o’clock.

Around back, the Blue Soul has two Speakon connectors as parallel outputs, and while the review unit delivers 650 watts into a 4Ω minimum load (or 350w into 8Ω), a 2.7Ω-rated model (650 watts @ 2.7Ω, 450 @ 4Ω, 240w @ 8Ω) is also available for those who want to run three 8Ω cabs, or combine 8Ω and 4Ω cabinets. The headphone out can be used without a speaker connected to the amp for silent monitoring, and separate footswitch inputs are included for the tuner and loop functions. The effect loop sends a +4dB mono signal to your effects chain with a mono return, and has it’s own gain control, but the LOOP/mp3 switch changes the EFFECTS RETURN jack to a mixable stereo input, controlled from the front panel. The full-featured balanced DI XLR out has ground lift, and pre/ post EQ switches.

The review amp came in with a full accessory package that included rack handles, a carry bag, and Glockenklang instrument, speaker, and power cords. There are various accessory packages available from dealerships. In the process of testing the amp, I A/B’d the sound of the Blue Soul with the different cables, as well as performing similar tests with my own reference amp, a Genz Benz ShuttleMAX 9.2. While I have no equipment to measure the difference, my ears clearly detected improvements in the overall sound with each of the cables. On both amps, the Hi-End power cord gave the lowest notes more clarity, while the speaker and instrument cables opened up the high end. It’s hard to quantify the effect of these improvements on a gig where you compete with the frozen margarita machine, but in the studio, you’ll surely notice the difference.

I plugged the Blue Soul into my Genz Benz Uber 212t cabinet and was struck by the immediacy of the response. Many amp geeks have complained that some Class D designs feel weak for their power rating or lethargic in their low-end response, but the Blue Soul exhibits none of these traits. The basic tone has a purity that could actually be described as “bell-like” (ja, Glockenklang!), and the power behind it seemed limitless. I tried several instruments, both active and passive through the rig and was frankly blown away with the presentation. Then, I realized that I had not yet engaged the EQ section! The EQ scheme is effective, with good control over the full spectrum, though for me, a semi-parametric midrange control would have been ideal. I could easily alter the tone for all the various sounds I need on a gig, but I kept going back to leaving the EQ out of the signal path altogether. If you have a great sounding bass, you will hear exactly that coming through this amp, but are your hands up to the challenge? Bad technique and degrees of slop will not fade into the mix with the Glockenklang—you will hear it all.

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Glockenklang has finally made the jump into the Class D amplification wars, and with the Blue Soul, has brought forth a mighty competitor. Players familiar with the company can rest assured that this “digital amp” can uphold the legacy of their more traditionally designed offerings, and fans of lightweight power will be glad to experience the translucent clout of the Blue Soul.



Street $1,930
Pros True to its name, the Glockenklang delivers bell-like clarity and fidelity to satisfy the most finicky audiophiles.
Cons None


Power rating 650 watts @ 4Ω
Power amp topography Class D
Inputs Two ¼" input (3Ω, 4.7Ω with trim), two ¼" footswitch (tune, effect loop), ¼" stereo MP3 in
Outputs Two Speakon, XLR balanced line out (pre/post eq), ¼" headphone out, ¼" tuner out
Controls GAIN, TRIM INPUT B, BASS (±15dB @ 60Hz), LOW (±12dB @ 130Hz), MID (±8dB @ 550Hz), HIGH (±12dB @ 4.2kHz), TREBLE (±15dB @ 12kHz), EFFECT/MP3 GAIN, EFFECT/ MP3 MIX, VOLUME
Dimensions 12.6" x 3.5" x 10.2"
Weight 11 lbs
Made in Germany


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