The VH4 is notable for its rare four-channel tube amp design, offering extensive tonal versatility.

The Blue Face Diezel is darker than the Silver Face version, with slightly less gain, enhancing low-end and mid frequencies.

The "Depth" knob on the Diezel adds a sense of depth to the low end rather than just increasing bass, offering a unique tonal control feature.

Channel 3 of the VH4 is particularly revered for its distinctive tone, often sought after by gear enthusiasts.

The VH4 has been a staple for heavy music, used by notable bands like Tool, Metallica, and Smashing Pumpkins, contributing to its iconic status.

Adam Jones uses the VH4’s channel 3 exclusively in live performances, suggesting it's crucial for maintaining his signature tone.

Adam Jones' setup often involves using different amps for specific tonal ranges: Marshall for lows, Diezel for mids and lows.

Owners often look to Europe for purchasing the BlueFace due to its rarity and possibly better availability compared to the US market.

The Diezel VH4 is compared to the Mesa Boogie Mark IIC+ in terms of iconic status, with both models commanding high prices due to their reputations.

The Blue Face Diezel fills in low-end frequencies and mids differently from a Marshall, which focuses on high-end and bite.

The reissue BlueFace is essentially a Silver with a blue front plate, offering no tonal difference but commanding a higher price.

Made in Germany, the VH4 is more expensive in the US, similar to how Mesa amps are priced higher in Europe due to import costs.

Original BlueFace models are considered distinct from reissues, with notable tonal differences, making them more desirable despite their higher cost.

Owners appreciate the VH4 for live use, noting its substantial output at 100 watts, often running it at around 60% power for performances.

It's been observed that some Diezel amps can get very hot during use, which may affect their performance if not properly managed.

Some owners retube their Diezel VH4 annually due to regular use, highlighting the need for consistent maintenance to ensure reliability.