I came across this strange idea yesterday.
What if you take digital audio material and inside Audacity expanded it to twice the duration.
That would give half speed playback.
Then I record that onto my B77 in half speed (3,75") as well and finally playing it on full speed (7½").
My first attemp gave a higher output in the treble area. It sounded more juicy.
The thoughts behind this is, that with half speed, the tapes when recording, doesn't have to deal with frequenzies over 8-10 KHz and that should give a cleaner and leave room for higher output.
Is this a result from different treatment that the B77 gives the tape in regard to bias/EQ with the different speeds ?
Or what exactly happens here ?
I need to do more tests.
Don't say it. It's probably a complete waste of time
But I like crazy ideas 😀
What if you take digital audio material and inside Audacity expanded it to twice the duration.
That would give half speed playback.
Then I record that onto my B77 in half speed (3,75") as well and finally playing it on full speed (7½").
My first attemp gave a higher output in the treble area. It sounded more juicy.
The thoughts behind this is, that with half speed, the tapes when recording, doesn't have to deal with frequenzies over 8-10 KHz and that should give a cleaner and leave room for higher output.
Is this a result from different treatment that the B77 gives the tape in regard to bias/EQ with the different speeds ?
Or what exactly happens here ?
I need to do more tests.
Don't say it. It's probably a complete waste of time
But I like crazy ideas 😀
Hi,
There is nothing wrong (or new) with half speed mastering, except
if your recording organ music or electronic subsonics which may suffer
slightly due to the bass overload characteristics of tape.
You are effectively making the recording head gap half width.
Given the frequency response at 3.75"/sec is not twice as bad
as at 7"/sec, you are effectively improving the 7" bandwidth
though the improvement wil be limited by the reply head gap.
🙂/sreten.
There is nothing wrong (or new) with half speed mastering, except
if your recording organ music or electronic subsonics which may suffer
slightly due to the bass overload characteristics of tape.
You are effectively making the recording head gap half width.
Given the frequency response at 3.75"/sec is not twice as bad
as at 7"/sec, you are effectively improving the 7" bandwidth
though the improvement wil be limited by the reply head gap.
🙂/sreten.
Hi Sreten.
Thank you.
I was aware, that the frequency response in both ends, would be different at the lower speed.
Therefore I was careful of not exceeding 0dB in any way.
In the lower end, there's more energy, given the halfspeed input.
That's why it was important not to hit the ceiling, so to speak or to saturate the magnetic layer.
The behavoir of the tape in the upper end, should also be different at 3,75".
The point where 3.rd harmonic reaches 1 or 3 % is lower, than with 7½", but not twice as low.
On top of that, input is never recorded, or "seen", by the tape with more than 8-9-10 KHz, so the limitations of tape in the high end is never present.
I did a recording full and halfspeed of Jean Michel Jarre "Oxygene Part 6".
The halfspeed recording clearly sounded as if a curtain was taken away.
I thank you once again for responding.
It was very useful and I appreciate it.
Thank you.
I was aware, that the frequency response in both ends, would be different at the lower speed.
Therefore I was careful of not exceeding 0dB in any way.
In the lower end, there's more energy, given the halfspeed input.
That's why it was important not to hit the ceiling, so to speak or to saturate the magnetic layer.
The behavoir of the tape in the upper end, should also be different at 3,75".
The point where 3.rd harmonic reaches 1 or 3 % is lower, than with 7½", but not twice as low.
On top of that, input is never recorded, or "seen", by the tape with more than 8-9-10 KHz, so the limitations of tape in the high end is never present.
I did a recording full and halfspeed of Jean Michel Jarre "Oxygene Part 6".
The halfspeed recording clearly sounded as if a curtain was taken away.
I thank you once again for responding.
It was very useful and I appreciate it.
Hi,
It would be very interesting if you do the same with a frequency sweep and report the B77 playback graph.
It would be very interesting if you do the same with a frequency sweep and report the B77 playback graph.
I agree. That would reveal some things.
I'm told, that the lift in the high area is caused by differences in EQ at 3,75" versus 7½".
Using a R2R taperecorder is a new thing for me.
In Spring 2007 I bought my first, which is now replaced with the Revox B77-mkII.
There are great discoveries and great disappointments still do be made for me.
Regarding a frequency sweep, I don't have equipment to do so.
Can you point me to some better freeware, than Audacity, which's capable of doing so, I'd appreciate it very much.
I'm told, that the lift in the high area is caused by differences in EQ at 3,75" versus 7½".
Using a R2R taperecorder is a new thing for me.
In Spring 2007 I bought my first, which is now replaced with the Revox B77-mkII.
There are great discoveries and great disappointments still do be made for me.
Regarding a frequency sweep, I don't have equipment to do so.
Can you point me to some better freeware, than Audacity, which's capable of doing so, I'd appreciate it very much.
DK6400Brian said:
Using this technique I would expect there to be a significantly rising response above a couple of kHz as the HF boost at 3 3/4ips is considerably greater than at 7 1/2 ips IIRC about twice the boost at a given frequency. (? Please correct me if I am wrong. ) I haven't thought this out, but I bet the mismatch is a whole lot of dB by 10kHz. 😀 Doing have speed mastering on tape I suspect the correct record EQ is probably not very different than that required for recording at 7 1/2 ips..
Using this technique I think you are overcoming to a small degree limitations in the record head performance, however I am not sure you are buying much else, and ultimately the bandwidth is limited by the playback head gap. (Another thought is that the high frequency energy on the tape may even start to saturate the head magnetics under some extreme conditions - measure thd..)
Try this technique with none electronic music (horns, quitar, etc) and I bet you will a tonal balance that sounds completely wrong.. 😀
Try the demo version of arta, or get the good and inexpensive audiotester software.
Well, the rise isn't that significant, as you indicate.
It's there, yes, but at the same time, I've been very careful not to exceed 0dB or peeking +3dB.
I've listened to my recordings of Jean Michel Jarre [MFSL] of Oxygene, Equinoxe and the Polydor 1981 edition of Le Chants Magnetiques and frankly my dear...On my pair of Sennheiser HD600, I really can't hear any outrageous tendensies. And they're not defect !
I understand so much this far, that recording to tape is a matter of handling the tape characteristics and doing it in two ways.
First off, is the bias, then comes the electronic compensations with EQ.
EQ is different at 3,75" and 7½", but what about 7½" and 15" ?
I was on the hunt for a little loophole and thought I actually might have found it.
Tape performance in > 10 KHz isn't excactly great with these "domestic" speeds, 3,75" and 7,5".
THD sets in too soon to my taste.
Since tape behaves that way, I had the thought, that I could cheat 😀
Ripping a track from CD, doubling the length, keeping it at 16bit 44KHz [equals a resampling of 88KHz], recording it at 3,75" and thereby eliminate the tape behavior above 10 KHz, seemed obvious from my point of view.
Now everybody tells me, that it's not good enough
[Just kiddin' 😉 ]
Okay. I get that the frequency response is altered in some way.
But turning a little button called "treble" down a few dB, could have the sideeffect, that the noisefloor too, is lowered to some degree
I've been focusing on the higher end of the frequency scale, but there's also the lower end to be considered.
I found this SID Sound In Depth software, which is free.
It should have a build in spectrumanalyzer.
Well. It's December in a matter of hours.
With all of this, in regards to taperecording, I think I have enough to examine in the long winter evenings.
Until everything is tested and so, I will have the purified joy in life of seeing these big 10½" reels turn round and round on this great taperecorder. I love it, man, I love it.
Good for Beethoven and good for Black Sabbath
It's there, yes, but at the same time, I've been very careful not to exceed 0dB or peeking +3dB.
I've listened to my recordings of Jean Michel Jarre [MFSL] of Oxygene, Equinoxe and the Polydor 1981 edition of Le Chants Magnetiques and frankly my dear...On my pair of Sennheiser HD600, I really can't hear any outrageous tendensies. And they're not defect !
I understand so much this far, that recording to tape is a matter of handling the tape characteristics and doing it in two ways.
First off, is the bias, then comes the electronic compensations with EQ.
EQ is different at 3,75" and 7½", but what about 7½" and 15" ?
I was on the hunt for a little loophole and thought I actually might have found it.
Tape performance in > 10 KHz isn't excactly great with these "domestic" speeds, 3,75" and 7,5".
THD sets in too soon to my taste.
Since tape behaves that way, I had the thought, that I could cheat 😀
Ripping a track from CD, doubling the length, keeping it at 16bit 44KHz [equals a resampling of 88KHz], recording it at 3,75" and thereby eliminate the tape behavior above 10 KHz, seemed obvious from my point of view.
Now everybody tells me, that it's not good enough
[Just kiddin' 😉 ]
Okay. I get that the frequency response is altered in some way.
But turning a little button called "treble" down a few dB, could have the sideeffect, that the noisefloor too, is lowered to some degree
I've been focusing on the higher end of the frequency scale, but there's also the lower end to be considered.
I found this SID Sound In Depth software, which is free.
It should have a build in spectrumanalyzer.
Well. It's December in a matter of hours.
With all of this, in regards to taperecording, I think I have enough to examine in the long winter evenings.
Until everything is tested and so, I will have the purified joy in life of seeing these big 10½" reels turn round and round on this great taperecorder. I love it, man, I love it.
Good for Beethoven and good for Black Sabbath
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