Aiwa AD-F810 Cassette Deck
This deck is a tremendous success on a variety of levels. The transport, for example, is about the most stable of any deck I have encountered in this price range. There wasn't the slightest instability of pitch in sustained piano or woodwind notes. Missing, too, was that subtle hardening of tone that betrays the presence of wow and flutter too rapid to register in any other way. This, plus a lower than expected level of modulation noise, meant clearer, more dynamic recordings.
The various Dolby circuits all worked well, too. The HX Pro circuit's effect was not testable - it can't be switched off - but Dolby B and C were unusually transparent, in part due to good tape alignment. Standard tapes of each type gave an accurate tonal balance without any tweaking of bias levels, and no sensitivity adjustment was needed to ensure proper Dolby tracking, though this won't apply to oddballs like That's Type II metals.
The Aiwa AD-F810 did nevertheless sound more open and lively without Dolby noise reduction. With material that masks the extra tape noise (rock and full-scale orchestral stuff, for example) it is worth investing in a quiet Type II tape like TDK SA-X, or a metal. This will give higher noise, but can also accept higher levels, allowing you to dispense with Dolby altogether. The compromise choice, which works with all types of music, is to use Dolby B which, though less powerful, is a little more transparent than C.
In practice, the Aiwa made its most impressive noises with metal tapes (I used TDK MA-X). These offered better projection, dynamics and solidity -related but subtly different properties. A recording of John Lee Hooker's My Dream (taped from CD using Dolby B) had a surprising fluidity, with the Aiwa adding nothing to the natural noises and background hiss on the disc's master tape.
Another track chosen for its resistance to being captured on tape was Schonherz and Scott's Wishing Well (from Kenwood's Windham Hill sampler). Here the use of opulent- sounding percussion generally sounds squashed and flat off tape, especially if you record in the usual way to slightly above OVU. Not so here - with the three-headed Aiwa, the music escaped its traditional mauling, as did the huge scale and lush sounding choral harmonies of the Brahms German Requiem.
The worst that can be said of the AD-F810 is that there was a faintly inarticulate quality noted with certain subtle musical nuances. This made the Brahms sound a little cold and distant. But these are fine details.