Sir Trefor and DBX
Sir T,
Pls email me when you can at cmk59@yahoo.com, and include your 'name' in the subject so I don't delete it. Would enjoy conversing off-forum with you and can answer/ask regarding DBX, trades, etc - so we don't gunk up the forum. Thanks!
Sir T,
Pls email me when you can at cmk59@yahoo.com, and include your 'name' in the subject so I don't delete it. Would enjoy conversing off-forum with you and can answer/ask regarding DBX, trades, etc - so we don't gunk up the forum. Thanks!
too bad...
All tape develpment stopped in the early '80s...crushed by the CD introduction.
But I still enjoy my Naka! Just wish they had a few more years, to implement Dolby S in those machines.
BTW, I have a pair of Dolby S modules fom a Sony, laying in my parts-box...it would have been fun making an external Dolby S unit!
Arne K
All tape develpment stopped in the early '80s...crushed by the CD introduction.
But I still enjoy my Naka! Just wish they had a few more years, to implement Dolby S in those machines.
BTW, I have a pair of Dolby S modules fom a Sony, laying in my parts-box...it would have been fun making an external Dolby S unit!
Arne K
Sir Trefor,
I had a look at the MF-P01. Much to my dismay, this box is even less than I imagined (I grew up on the first portastudio, the 144, in the 80s). One should not expect ANY level of quality from this thing, I'm sorry.
Adding external noise reduction to it won't help, as either Dolby or dbx rely on the proper matching of levels going onto and off the tape, and over the full frequency range (i.e. no treble saturation allowed). This is unattainable with the MF-P01.
If you want to stay analogue, I recommend you hunt down a 4-track reel-to-reel in decent shape, and then add a small mixer. That way you won't even need noise reduction.
A valid alternative is a laptop with a decent external sound box, using your R2R for mastering and adding the analogue feel.
I had a look at the MF-P01. Much to my dismay, this box is even less than I imagined (I grew up on the first portastudio, the 144, in the 80s). One should not expect ANY level of quality from this thing, I'm sorry.
Adding external noise reduction to it won't help, as either Dolby or dbx rely on the proper matching of levels going onto and off the tape, and over the full frequency range (i.e. no treble saturation allowed). This is unattainable with the MF-P01.
If you want to stay analogue, I recommend you hunt down a 4-track reel-to-reel in decent shape, and then add a small mixer. That way you won't even need noise reduction.
A valid alternative is a laptop with a decent external sound box, using your R2R for mastering and adding the analogue feel.
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Gentlemen,
I just got a Teac RX-98 dbx unit. Does anyone know what modifications shall be made in order to operate this one as a stand alone unit? Cause of legal considerations (TEAC could not sell DBX stand alone units) this is controlled by a cable remote through TEAC or TASCAM (122b cassette tape recorder). Therefore I would be tempted to believe the modifications are not so important.
Thanks you for your time in reading this!
Gabriel
I just got a Teac RX-98 dbx unit. Does anyone know what modifications shall be made in order to operate this one as a stand alone unit? Cause of legal considerations (TEAC could not sell DBX stand alone units) this is controlled by a cable remote through TEAC or TASCAM (122b cassette tape recorder). Therefore I would be tempted to believe the modifications are not so important.
Thanks you for your time in reading this!
Gabriel
One more example of blameless noise reducer
There are two main requirements a nearly ideal noise reducer should meet.
The first is its universality and ability to cope equally well with noise of
any nature, whether it is a tape hiss, vinyl disc surface noise or noise of
the electronic components (transistors, resistors).
The second requirement is minimum intrusion to the signal to be processed,
its dynamics, distortion and other important characteristics remaining the
same as before the noise reduction.
Subjectively, the tone balance of the reproduced sound has to be unchanged too, the only perceived by the ear difference between the original
and processed sound should be the disappeared hiss which is particularly
annoying in cassette tape recordings.
Fifteen years ago I built just such a noise reducer and since then I haven't
anymore neglected listening to my cassette tape collection created in the
eighties.
Information about this device can be found at the site Only Live Audio , there are also the downloadable clean and noisy versions of the same soundtrack for using them in listening comparisons.
Vladimir.
There are two main requirements a nearly ideal noise reducer should meet.
The first is its universality and ability to cope equally well with noise of
any nature, whether it is a tape hiss, vinyl disc surface noise or noise of
the electronic components (transistors, resistors).
The second requirement is minimum intrusion to the signal to be processed,
its dynamics, distortion and other important characteristics remaining the
same as before the noise reduction.
Subjectively, the tone balance of the reproduced sound has to be unchanged too, the only perceived by the ear difference between the original
and processed sound should be the disappeared hiss which is particularly
annoying in cassette tape recordings.
Fifteen years ago I built just such a noise reducer and since then I haven't
anymore neglected listening to my cassette tape collection created in the
eighties.
Information about this device can be found at the site Only Live Audio , there are also the downloadable clean and noisy versions of the same soundtrack for using them in listening comparisons.
Vladimir.
Hi guys maybe i can get some help, i just got a hold of a teac A-4010 sl, and the only thing that works is the sourse section, i want to know if there is an easy way to detach the lower section from the tape section and add power to it to rack mount it. Would like to know how to ad power to the lower section once detached. Thanks
Hi Sir Trefor,
this may well be a bit (or way) off topic as I am not familiar with all the dbx model numbers that you refer to but if you wish to DIY your own wideband "compander" there was a very helpful article (and subsequent addendum where they corrected some graph scales as I recall) in the JAES some maybe 35 yrs ago, not exactly sure when. It was the product of some sensible experiments that gave good material to build your own compandor. They addressed "pumping" and looked at various averaging systems (RMS, peak etc) and came up with recommended time constants for a multiband system............I think they looked at treble pre-emphasis too.
(I don't know what things are like State Side but down here many engineering libraries hold the JAES in their "stacks" but you seem to know what your doing so that will not be a big issue)
It strikes me that if you wanted to you could use the NE570/571/572 series of ic's to knock up something interesting. The NE572 is a stereo IC with provision for variable attack/decay times and THD null.
Anyway hope this is not too off track.....
On the other hand given that the original poster has not been active on the forum for over 7 yrs we may well all be wasting our time too..............
Cheers, Jonathan
this may well be a bit (or way) off topic as I am not familiar with all the dbx model numbers that you refer to but if you wish to DIY your own wideband "compander" there was a very helpful article (and subsequent addendum where they corrected some graph scales as I recall) in the JAES some maybe 35 yrs ago, not exactly sure when. It was the product of some sensible experiments that gave good material to build your own compandor. They addressed "pumping" and looked at various averaging systems (RMS, peak etc) and came up with recommended time constants for a multiband system............I think they looked at treble pre-emphasis too.
(I don't know what things are like State Side but down here many engineering libraries hold the JAES in their "stacks" but you seem to know what your doing so that will not be a big issue)
It strikes me that if you wanted to you could use the NE570/571/572 series of ic's to knock up something interesting. The NE572 is a stereo IC with provision for variable attack/decay times and THD null.
Anyway hope this is not too off track.....
On the other hand given that the original poster has not been active on the forum for over 7 yrs we may well all be wasting our time too..............
Cheers, Jonathan
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I don't know which tape speeds you use on your master recorder, but full-track 38 cm/s (15') with correct recording calibration on a high quality tape may eliminate all necessity for noise suppression, while also extending the dynamic range and keeping the signal paths clean. Eventually, modernisation of eletronics and replacing older components, particularly transistors for quieter ones, may improve overall S/N ratio of a tape recorder.
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Hi
Sourcing the DBX 150x using the NEC chips will save you wasting many years
of trying to replicate how good a compander can be. The 150x IMO was the
best followed by the 180a then 155, with the 150 after that.
A schematic for the 150x and many other models is here
dbx Professional Audio
Whilst it will be interesting building a compander using other
discrete devices, you need to consider the many years of
development DBX made. Source a 150x and be happy
Cheers / Chris
Sourcing the DBX 150x using the NEC chips will save you wasting many years
of trying to replicate how good a compander can be. The 150x IMO was the
best followed by the 180a then 155, with the 150 after that.
A schematic for the 150x and many other models is here
dbx Professional Audio
Whilst it will be interesting building a compander using other
discrete devices, you need to consider the many years of
development DBX made. Source a 150x and be happy
Cheers / Chris
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