about this recording, the mic amp had been upgraded , I add 16 caps more to the amp in by pass position each position not only one cap is carry two more smaller value cap for more signal go through , tubes are 1950's we 300b and we 437a. if you have chance to compare the analogue version (tape)...
I did a all tube amp direct from head, EQ by a simple passive LCR filter no calibrate (A80's section is silicon feed back type) transformer coupling and out put ( not silver copper only) very simple just like a phono RIAA amp, sound good tube use 5687 or 7119 or 6900 of cause best sounding is...
Hi Victor
I am Tony who built the amp . the construction of A80 playback amp is in 3 parts is EQ calibrate and out put stage. the amp's in put is from calibrate part's out put before A80's volume control to a silver inter stage transformer 1:2 then 300B and a out put transformer 600 ohm output...
Out broad amp is a kind of up grade of tape recorder but how to connect to the head is a question. closer is better too far away (too long cable or weirs) will create problems. here what I did with A80RC A810 and PR99
In A80RC very simple use two extra card (pictures) to replace repro card...
I have a box set (3 vinyls) of Audio Technical Records by DENON, this testing vinyl produced by professor Takeshi Itow doctor of engineering Waseda University, Tokyo Japan. the recording is for people to check their play back system, it contain sweep frequency, band noise, phasing, musical...
For a general R2R consumer to enjoy pure analogue sound of music in play back, the most important things for them to do is often clearing heads' surface and tape path too and demagnetize heads . a demagnetizer will not cost too much money than a set of test tape but can give a great help in...
After we placed a battery power to the repro amp of A80 to replace the stock voltage regulated power supply and found improvement but in the first try same to record amp was disappointed , there was some radio broadcasting mixed into the recording too, we found long wire and bad routing caused...
I don't know how to measure difference of transparency, emotion,sound stage, sound density, etc, all I know comparison will tell about, of cause basic tuning we did every time before recording by qualify person still came out so different in each modification of transparency, emotion, sound...
Hi Tang
That switch is for you when in fast winding for tape will not touch heads, you no need pair of UV meter fix to amp unless you want to watch when playing. to buy a HP AC volt meter in old analogue type (from Ebay) for adjusting out put level , also you can buy two of them for both...
Is Studer the best in the world ? yes maybe in their golden age but by no mean it can't be improved today ! once people put their hand into the machine of modification will losing resell value but you can ask Ed will he sell his two Studer A80 in what ever of money will offer, the changed after...
I am sure that is the reason, although I don't know the detail of A820 but I know A820 has same looking transport of A80 and circuitry same as A810, then I think it may also has a pre amp behind the head too and the guy modify the deck for you is place the switch selector before the repro amp...
Doshi in Mike's A820 and Steve's A810 both working OK for Ed's tape, I checked with the Studer A810 service instructions the transport is no change but different year made in different electronic circuit design some with transformer but some is transformerless because of different impedance head...
It is hard to say worth $ or not, I just brought two pair of Hejiri inter connect cables back from Japan for my friend's request paid $6k but today you can only just pay under $2k for a 65" TV, tube amp came back after they completely disappeared and most Hi End market of today is tube amp...
Yes he said when he play Ed's he connected A820's out put to his pre amp (line stage ) not Doshi, and he has a switch selector for head to Doshi or back to A820, and I don't know what type head in his A820, in A80 RC and A80VU has different impedance head, RC type's head has higher impedance...
One more thing, you said a tiny adjustment will have a big change in loudness that means even a low out put tape still has a too much gain in the amp's out put so that is why even the lowest the gain still over load for Ed's tape. I guest that is the head has higher out put for Doshi's gian...
Yes your connection is correct , Ed's tape has a 1k Hz signal test tone recorded in the beginning of each tape what you can do is to have a level tester or a VU meter connect to the Doshi out put and play the test tone to see if you can adjust to the out put in 0db, if you can make this happen...
Can you tell me how you connect the Doshi to your A820? if direct from the head and how you play Ed's tape by the stock A820 itself ? as I know that Doshi is a Hybrid design most of it is tubes but it needs more gain for those low out put tape in low level recorded (250nw) so he put one more in...
I have no knowledge of cutting vinyl but I do know that direct cut vinyl is the best than others as you said a digital time delay circuit in between signal and cutter then a digital sound will be added to the vinyl sound, in my knowledge even a analogue power supply for a analogue amp...
Copies from master tape can't be quality 100% same as the master especially transparency must down for some %, people who using out broad play back amp instead stock amp in their deck will understand what happen . for vinyl cutting sound quality is depend the in put quality too, most of today's...
I do believe that changed in big different. better or worse will depend to the listener himself , even just change some caps of the original in the circuit will change the sound quality too, measurement can't tell the difference
tony ma
Not bad I started with the pr99 too,one tweak you can try is to use the monitor out instead of the regular out can sound better if your line stage has enough gain
enjoy
tony ma
what factors will be more important for a good recording ? in my experience those can't be measured factors like transparency, emotion, sound stage, are more important than those measurable like frequency respond or distortion because those measured numbers can be changed by adding heavy NFB in...
CCIR & NAB curve are the kind of frequency respond and that is only related for the tape head and tapes in recording and play back, if they are working right then there is no different between or which one is better than other. reason is more other frequency responds like mic amp speaker room...
Thank for the appreciation key point of this time is the pure DC (battery) power supply, if you can compare the last time Beethoven violin sonata no.9 same Tatsuki & YY, WE 300B is the same but not battery power you will know the difference , in this point I would like people can understand...
Hi Mike
I hope you will find out the difference as I did from this new recording with battery powered when they release, that is the sound of silence , that is the dark silence period between two music signals and you still feel live there not dead. compare to the silence sound from a no...
I will not listen music which I don't like (heavy metal rock etc.) too no matter how good they are but I will only pick the music of I like with better performed and recorded
tony ma
Do audiophile really need recording by themselves today ?
Audiophiles in today looking for tape because some thing vinyl does not have, but quality of recording is the first issue , if copy by themselves from digital or vinyl or other tape will not be the point , should be to make your own...
I have B62 and A80 both machine and know them quite well, for recording calibrate you need calibrate the play back with a test tape first and set level meet to the test tape, also need a VU meter for B62 for the job. and then use a signal generator for recording signal to set the level and bias...