What year is the catalog? The Transcendental cataolg MBarney posted on Google I lost many years ago has some different dimensions . You can find it by doing a general search of Dalesford woofers. The 10" vesrions I have are magnet diameter 135mm, voice coil diameter 55mm and it is cloth covered not plastic, and depth around 115+mm. It has been years since I built the enclosures and lost written records of all the specs Fried told me. I know Fried used the D300 motor on his 10" 81 versions before the company closed. There were copies made by Mission Electronics under the Dalesford, Cambridge name. I have corresponded with many U.K. companies over the years that don't know the full story behind the company. Being a history buff it would be nice to know the full story. I was told the Bl is 12 and Vas around 170L it explains why they perform well in t-lines. I think Erfeller has the Fried versions. I was told Fried had a 5" version made in last B2 models with larger motor that were superior to the Kef B110.
