What voltage is it at the output of Q4? Is clipping symetrical?bjoneson said:The clipping occurs in the rec preamp stage around Q4, as you stated. That's the bottleneck. When that stage clips, I'm still a good 2-3dB shy of the 1% 3rd harmonic spec on modern tape (using ATR).
At the times it's been designed, many engineers had not made the transition from tubes to SS; maybe they were more comfortable with RF concepts, such as common-grid (that translates into common-base) for HF performance...?I didn't realize just how low the input impedance of the main record amplifier was until I took a closer look after you mentioned it. I'm intrigued, because most of the theory I'm comfortable with is with high impedance inputs.
Well, there's room for improvement here; that would not impact the quality of recordings though. Just monitoring and playback.You are also correct in regards to the placement of the VU, it's literally strapped right across the secondary of T2 (which is 1:1), right after the line amp.
I made an abrupt transition from tape to digital, fortunately escaping the whole folly of DAT, BVU editing, 8"-floppy-based automation; that's because I didn't have to make a living on this.As an aside... I'm 31 years old. My first studio experience as a teenager was with blackface ADATs. I missed the entire era of analog tape, but have a tremendous fascination and respect for the great many people who pioneered and cultivated the craft of recording on this medium. It appears to be an era in which recording *engineer* really meant something. I have no misconceptions that tape is magic, and I'm not chasing a particular sound. But I do find modern recording tools make me feel very detached from the engineering side of things. It's too easy I think. Knowing you're working with devices and tools that real people, with real hands, who take real pride in their work, spent countless hours creating (as opposed to an assembly line in china) has an impact on the quality of work you do. At least it does for me.
I'm happy to be free of constantly watching needles, and yet having hiss issues, weird kick-drum sound, pesting about the missing 25th track and the flanging sound of tracks 1 & 24.
OTOH, I'm always in awe when I see a tape machine, equally for a Studer A8xx (the pinnacle of no-compromise design) as well as a 1970's Grundig or Philips (how to build a workhorse at a price).