True and Fake Dual Mono Amplifiers

 Dual Mono Amplifiers: TRUE and FAKE

True "Dual-Mono Amplifier" should be designed as a two "Mono Blocks" in on enclosure and if possible provide the galvanic separation of channels, which is hard to archive because of the mechanical concerns (sockets) and the fact that typical built-in pre-amp usually has a single PSU.
There is a lot of so called "Dual-Mono" amplifiers, which just have two transformers instead of one, but the electronic design is exactly the same as in any common stereo amplifier.
The easiest way to tell if the amplifier is true of fake "Dual-Mono" is to count how many the biggest, but the same in size and parameters capacitors it has: if 4, 8, 12, ... (4 multiplied by any positive natural number), most probably it is designed as a "Dual-Mono", but if there are only 2, or 2 big + 2 also big, but with a different size - it's just an ordinary stereo amplifier.

The list of TRUE "Dual-Mono" amplifiers

TRUE "Dual-Mono" designed as two mono-blocks in one enclosure:

• Balanced Audio Technology VK-500

TRUE "Dual-Mono" with two transformers, 4 power sections:

• Audio-gd A1 
• Harman Kardon A-402
• Music Fidelity A300
• Pioneer A-77X
• Rotel RB-850
• Sansui AU-717
• Technics SU-8080

TRUE "Dual-Mono" with one transformer, but also 4 power sections:

• Adcom GFA-585
• Hafler XL600 
• Harman Kardon HK870
• Harman Kardon HK6850
• Harman Kardon PA2400
• Sherwood AM-8500G
• Grundig V5000

The list of  FAKE "Dual-Mono" amplifiers

FAKE "Dual-Mono", with two, but single power section transformers instead of just one:

• Denon PMA-A100
• Denon PMA-925R
• Kenwood KA-80
• Kenwood KA-7010
• Kenwood KA-7020
• Pioneer A-91D
• Pioneer A-717 
• Pioneer A-757
• Sherwood AX-7R
• Sherwood AX-9030R
• Sony TA-F570ES