![]() ![]() As short as possible.ĪKAI is an good example, just a-b switch tape/source (tape-monitor on deck is 2nd) on your preamp and compare! So folks, get an buffered amp or -as Lucky said - a linedriver, ideally with short wiring to the deck or: Exceptionally good and low impedance/capacity cables. And surprisingly this one is acclaimed to be quite good. The only Tapedeck, I remember at the moment having an output buffer is the Cambridge CT-50. And even very expensive ones without Dolby-bypass use the complex de/encoder IC as a line driver. (Or believe of the engineers in such needs.) Most tape outputs like this AKAI are fed directly from a Dolby-IC (or to be precise EQ-preamp without Dolby). The AKAI is same as almost all consumer-ware tapedecks, there was no budget for buffer input and output stages. I think this is much more common as a problem with the tape out, but only with a switch as on this AKAI you can hear the effect. Symphonic line line-amps and CD-output stages can, plug out or at least turn your volume to 5-o clock when not listening to tape and whenever possible by level, use the cd-in for recording on this tape. So this tape is sensitive for source impedance, and if you don’t use one of the very amps with an buffered tape out for source, or have a line-source, able to handle even a real speaker, like e.g. My Sugden-preamp as most preamps is passive at the tape output (for British Hi-Fi, I only recognize Exposure Preamps having a tape-out buffer stage) so if a source is fed into the tape (and preamp), the angle of potentiometer on the AKAI unfortunately effect the sound both of the tape recording and the listening by the complexe impedance of all cables etc., the first a bit more, the second a bit less. This leads to the alternative: It’s even not of a problem of the deck but of the recording-source including all the cable sound. Even a M5238S is able to handle 11dB properly with it’s open-loop gain of 100dB. IMO and experience this is not mainly a effect done by the buffer-gain. As soon you plug the cables to the other input and take the „cd“ with lower gain and a potentiometer almost on the 5-o clock-side, the sound is much much more crisp and dynamic. I really wondered about the flat, undynamic sound both listening to „tape“ and „source“, when using „line“. So with a line source you have 2 opportunities: higher poti-resistance and higher gain or almost 0 resistance and low gain around 1 for the op. Here in addition a gain of 3,6 / 11dB is switched, depending on „line“ or „cd“. There are both line and CD-inputs, switchable some cm away from the input, leading via PCB to the rec-potentiometer in the front and to an quasi-buffer-op-IC M5238S. So slow down for the moment before telling me, how bad this all is and which of my decisions were futile. For a “what is possible” at the moment I have no comparison with one of the top-class decks. ![]() Tonality is good but not finalized, the 105°-caps need some months for getting their final level of tonality. The sound is not perfect, but really surprisingly good for a deck, the deck is able to see all 3 dimensions in soundstage as given, most certainly a lack of all the brutal attack, I’m used to on my listening system. The modded supply will let this vanish and cleans almost all of the unmodded „clamp on the head“-distortion sound completely, which you can hear on the original deck and which I‘m not able to take from any kind of Hi-Fi. (All the amp-stages of AKAI GX75 Mk2 are by the way fed by unclean hefty supply ripple from 50Hz to 3kHz(!!), mostly of it from the supply board around the “dirty”-switching rectifier-diodes. But even if one disagrees, we still can learn from each other, me and you.īut there are some interesting results to tell after finishing and fully modding a AKAI 75 Mk2 with hints most of it from forum, and yes, Lucky, I agree in OPA2604, which I also used for modding. Also I feel this forum sometimes reads like personal property of old -and of course well served- members *boxing*. ![]()
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