Category Archives: Amplifiers

Articles about amplifiers, including power amplifiers, integrated amplifiers, big and small amplifiers, solid-state and tube amplifiers!

Marantz 1152DC Integrated Amplifier Repair & Restoration

How’s this for a beautiful amplifier. I recently repaired and restored this absolutely stunning Marantz 1152DC integrated amplifier, let’s take a look.

The Marantz 1152DC is an integrated amplifier from the upper middle of Marantz’s range in the late 1970’s. The 1152DC and others from this series are very collectible now, thanks to their unique looks, great sound and Marantz’s famous build quality. … Read more

Transistor Matching for an Accuphase E-202 Amplifier Repair

I’m repairing a gorgeous Accuphase E-202 integrated amplifier and there’s a need for careful transistor matching in audio gear like this.

Choosing and matching transistors correctly is critically important when repairing or restoring audio electronics. I’ve learned this over the years, through experience and from people who’ve been doing this for much longer than I have.… Read more

Accuphase P-600 Monster Stereo Power Amplifier Voltage Conversion

Holy balls, the Accuphase P-600 Stereo Power Amplifier is one B-I-G mother of an amplifier. It actually gets physically tiring moving these beasts around the workshop!

Anyway, I’m not complaining, I LOVE working on equipment like this, even if it is heavy and the work slow. The Accuphase P-600 was, as far as I recall, Accuphase’s best class A/B stereo power amplifier back around the early 80’s.… Read more

Shocking Latest Krell & H/K Hall of Shame Additions

These latest additions to the Hall of Shame are two of the worst cases of hi-fi electronics bodgery I’ve ever seen. The destruction of this Krell KRC preamp by a so-called expert must be seen to be believed.

What follows are snippits from my latest Hall of Shame cases. Visit my Hall of Shame for all the horrifying details, more photos and more detailed descriptions, plus even more cases.… Read more

Sony TA-4650 VFET Amplifier Service & Reliability Enhancement

I’m reluctant to use the word ‘sexy’ when it comes to hi-fi gear because, well – it just feels weird. If I were to use it though, it would be about this baby Sony TA-4650 VFET amplifier.

What can one say after working one of these stunning Sony TA-4650 VFET integrated amplifiers? I really fell for this little beauty and came to understand why so many people treasure these amps.… Read more

Luxman SQ-202 Integrated Amplifier Repair & Service

I get to work on some beautiful gear at Liquid Audio. A great example is this stunning Luxman SQ-202 integrated amplifier that I’ve just repaired and serviced.

The Luxman SQ-202 integrated amplifier is a model dating right back to the early 70’s. In fact it was released 1970, and produced until 1973.

Lots more great information and specifications are located at the Vintage Knob page for the SQ-202.… Read more

Krell KAV-300i Integrated Amplifier Repair & Restoration

I’ve just repaired and restored this lovely Krell KAV-300i integrated amplifier. Read on to find out how I did all that, and why the KAV-300i is such a superbly engineered amplifier.

Krell still proudly builds amplifiers and other high-end gear, from their base in Orange, Connecticut, USA. Established in 1980, they set about manufacturing a range of really different hi-fi equipment, aimed squarely at the top end of town.… Read more