any of you out there playing 78 rpm's still? if so, what kind of setup are you using?
as of now i feel i have the choice of either buying a secondhand thorens or the like and having an entire second tt dedicated to 78's, or. . .
if i could in any way add a new controller to my existing outboard motor to add adjustable 78rpm to it. . . or something of that variety.
anyhow, just wondered if and what rigs any of you out there are running for 78. thanks
as of now i feel i have the choice of either buying a secondhand thorens or the like and having an entire second tt dedicated to 78's, or. . .
if i could in any way add a new controller to my existing outboard motor to add adjustable 78rpm to it. . . or something of that variety.
anyhow, just wondered if and what rigs any of you out there are running for 78. thanks
You can use a 78 stylus for your cartridge.
Or have interchange headshells, here weighting the headshell
so you don't need to readjust the arm is a possibility.
Some turntables have two arms fitted.
Many turntables can be modded to give 78 rpm, either electronically or a with a custom motor pulley.
Depending on the PS type to your motor it could be easy to mod.
I don't run 78's.
sreten.
Or have interchange headshells, here weighting the headshell
so you don't need to readjust the arm is a possibility.
Some turntables have two arms fitted.
Many turntables can be modded to give 78 rpm, either electronically or a with a custom motor pulley.
Depending on the PS type to your motor it could be easy to mod.
I don't run 78's.
sreten.I recently bought a new DJ turntable for this purpose (JBSystems High Q30D around 250 euro). I don't know why, but a lot of new DJ TT's include 78rpm. And to have a variable speed is also good, as not all 78rpms are 78rpm! Some of those I have around are marked 80rpm. So having 10% variable speed is useful.
As for a cartridge. You can try to find a generic 78rpm one Apparently, the radius can vary quite a lot. 2.8 um to 3 um is some kind of general purpose median value. Stanton for example has 78rpm styluses for their cartridges, and can provide custom ones if you want it.
As for a cartridge. You can try to find a generic 78rpm one Apparently, the radius can vary quite a lot. 2.8 um to 3 um is some kind of general purpose median value. Stanton for example has 78rpm styluses for their cartridges, and can provide custom ones if you want it.
as far as arm & cartridge & phono amp for them go i think i've got a handle on that, i mainly just need either another deck, another motor, or a way of modifying my current outboard motor to rotate at 78 rpm (with of course adjustablility enough to go from around at least 76 to at least 80).
if i can either modify mine, or add another motor to my existing deck i can easily add another tonearm to the setup.
if i can either modify mine, or add another motor to my existing deck i can easily add another tonearm to the setup.
Hi Jesser
I am using a seperate TT for my 78s, in this case it is a Technics SP15 (my main TT is a SP10 MkII). Most important is to get a proper outboard phono-stage for your 78s. They won't sound correct without it. And like Havoc said, it is important to have speed adjustment. Then you just need to enjoy it
Enjoy,
Deon
I am using a seperate TT for my 78s, in this case it is a Technics SP15 (my main TT is a SP10 MkII). Most important is to get a proper outboard phono-stage for your 78s. They won't sound correct without it. And like Havoc said, it is important to have speed adjustment. Then you just need to enjoy it
Enjoy,
Deon
Nothing at the moment, unfortunately. I was going to DIY one 
, but then a lot of the parts needed for the project got lost during a house move, and I've not been able to replace them yet. 
I still want to finish that project, but there are so many projects vying for the little amount of spare cash I have that it will have to wait for a while. One of the projects ironically enough is to build shelving to store my collection of 78s in the place I am staying in now. 
Ah well, I will get to it soon enough. For the moment though I will have to content myself by playing normal LPs.
Enjoy,
Deon
, but then a lot of the parts needed for the project got lost during a house move, and I've not been able to replace them yet. I still want to finish that project, but there are so many projects vying for the little amount of spare cash I have that it will have to wait for a while. One of the projects ironically enough is to build shelving to store my collection of 78s in the place I am staying in now. Ah well, I will get to it soon enough. For the moment though I will have to content myself by playing normal LPs. Enjoy,
Deon
Havoc said:
Eeek! Bear in mind that even 78 equalisation can encompass 30dB of dynamic range from the level at low frequencies compared to extreme HF. In other words, you have just raised the noise floor at LF by 30dB. If you then consider that 78s have lots of pops and clicks, you will have to lower the level fed to the soundcard to ensure that they don't cause digital overload. Another 12dB would probably be advisable. Simply doing arithmetic on numbers and rounding them back to the same number of significant digits causes quantisation errors that must be dithered, knocking off another 3dB.
Applying disc equalisation digitally uses up so much dynamic range that there may not be much left for the music! Inconvenient though it is, analogue will be better than digits.
No, I don't have 78s, but I've looked into the electronic problem for people who do.
It is not that bad.
First of all, I use a 24bit conversion. So low levels are not a problem. Next, with a bit of care you can go up to -3dB at the input without any problem. If the pop is so big to possibly clip the input, you will need to cut it out anyway, so you loose nothing. Finally all subsequent work is done in 32bit floating point, so this introduces no clipping and makes sure rounding is no real issue until final conversion to 16bit for CD.
While analog EQ may be indeed a bit better, the problem is that there are about 10-12 curves. I don't like to put loads of switches in such circuits, and at the same time like to keep them compact. So it would mean 10-12 preamps. It can also be a hit and miss finding the best EQ for a given record. Certainly if some obscure label and you cannot date it for certain. So doing this digitaly is a lot easier.
First of all, I use a 24bit conversion. So low levels are not a problem. Next, with a bit of care you can go up to -3dB at the input without any problem. If the pop is so big to possibly clip the input, you will need to cut it out anyway, so you loose nothing. Finally all subsequent work is done in 32bit floating point, so this introduces no clipping and makes sure rounding is no real issue until final conversion to 16bit for CD.
While analog EQ may be indeed a bit better, the problem is that there are about 10-12 curves. I don't like to put loads of switches in such circuits, and at the same time like to keep them compact. So it would mean 10-12 preamps. It can also be a hit and miss finding the best EQ for a given record. Certainly if some obscure label and you cannot date it for certain. So doing this digitaly is a lot easier.
All good points, especially the 32 bit and rounding issue.
Your point about the lack of problem with large clicks being clipped is interesting. I would expect there to be a buffer between the input sockets and the A/D. If they are well matched, the buffer may not have any significant headroom above the A/D. Clipping the buffer might cause latch-up, prolonging the length of the click. It might be worth investigating.
When looking for curves, I was looking mainly for pre-RIAA LP equalisation. I found that to cover all possibilities, a 12 position switch was needed for bass eq and another for treble. If you reckon you only need 10-12 settings for 78s, you are getting off lightly. Still, it makes digits attractive.
Your point about the lack of problem with large clicks being clipped is interesting. I would expect there to be a buffer between the input sockets and the A/D. If they are well matched, the buffer may not have any significant headroom above the A/D. Clipping the buffer might cause latch-up, prolonging the length of the click. It might be worth investigating.
When looking for curves, I was looking mainly for pre-RIAA LP equalisation. I found that to cover all possibilities, a 12 position switch was needed for bass eq and another for treble. If you reckon you only need 10-12 settings for 78s, you are getting off lightly. Still, it makes digits attractive.
Good point. I do now the preamp can output to +/-12V before coming into trouble. So it would be inside the AD. Could not really find any specs on that. But I haven't yet seen it, but this is no garantee. The Ad has a setting for inputs upto 0dBFS@+19dBV, but as the gain structure is unknown, again it tells you nothing.
Now if you have a click, the application itself looks at the spectrum before and after and fill in according to that. So the click itself is not used for this. If the latch-up would occur, it would simply mean you have a slightly larger click to fill. As clicks can be several ms long, I don't think it would be a problem. But it is certainly something that needs to be checked before you start processing.
The digital route is attractive, but as I have no analog alternative, it is hard to tell if it really is an alternative. I guess it depends on what you want to achieve. For me it is nothing more that being able to listen to those discs. And I don't have enough of them around to justify an analog preamp.
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