I connected my old Technics SL-D202 turntable via the RCA audio output to an RCA to mini-stereo splitter, and into my sound card's Input mini- stereo hole.
I slid the Input sliders all the way up (in both recording and playback mode), but the sound coming through my computer speakers is pretty low, as is the recorded wav file (using Audacity and VinylStudio).
I know I can boost the sound on the audio in Audacity (or any audio software) but there is a lot of hiss so I'm not sure this will produce a nice recording. I guess to ask the question is to answer it, but should I be connecting the turntable into a stereo amplifier and then the amplifier into the computer? Or is there another solution?
On 24 Feb 2008, Thumper <thumperstra...@gmail.com> wrote in rec.audio.pro:
> I connected my old Technics SL-D202 turntable via the RCA audio > output to an RCA to mini-stereo splitter, and into my sound card's > Input mini- stereo hole.
> I slid the Input sliders all the way up (in both recording and > playback mode), but the sound coming through my computer speakers > is pretty low, as is the recorded wav file (using Audacity and > VinylStudio).
Phonograph cartridge output must be pre-amped and EQed to specifications written by the RIAA in the 1950s. You need to run your turntable into such a preamp, then into your sound card.
The preamps are available at just about any price point. Radio Shack has a cheap one:
> I know I can boost the sound on the audio in Audacity (or any audio > software) but there is a lot of hiss so I'm not sure this will produce > a nice recording. I guess to ask the question is to answer it, but > should I be connecting the turntable into a stereo amplifier and then > the amplifier into the computer?
Yes. Use a dual-RCA > mini-stereo cable, and connect the RCAs to the tape outputs of your stereo amplifier, and the mini-stereo to the LINE input of your computer. Connect the turntable to the phono input of the amplifier, and don't forget to hook up the ground wire.
> > I slid the Input sliders all the way up (in both recording and > > playback mode), but the sound coming through my computer speakers > > is pretty low, as is the recorded wav file (using Audacity and > > VinylStudio).
> Phonograph cartridge output must be pre-amped and EQed to > specifications written by the RIAA in the 1950s. You need to run your > turntable into such a preamp, then into your sound card.
> The preamps are available at just about any price point. Radio Shack > has a cheap one:
Which is unfortunately awful. The OP's suggestion of an older stereo amplifier is a better idea.
Thumper <thumperstra...@gmail.com> wrote: >I connected my old Technics SL-D202 turntable via the RCA audio output >to an RCA to mini-stereo splitter, and into my sound card's Input mini- >stereo hole.
And you have very low levels and no bass at all. You need a phono preamplifier. --scott
-- "C'est un Nagra. C'est suisse, et tres, tres precis."
On 25 Feb 2008, "Paul Stamler" <pstamlerh...@pobox.com> wrote in rec.audio.pro:
> Which is unfortunately awful. The OP's suggestion of an older > stereo amplifier is a better idea.
I'm sure it's not great, but is it any worse than the preamps built into the typicaly inexpensive stereo receiver? Or are you saying that just because it's Radio Shack branded?
<rednoise+n...@REMOVETHIScomcast.net> wrote: >> Which is unfortunately awful. The OP's suggestion of an older >> stereo amplifier is a better idea.
>I'm sure it's not great, but is it any worse than the preamps built >into the typicaly inexpensive stereo receiver? Or are you saying that >just because it's Radio Shack branded?
I imagine it's the cheap USB a>d interface that's crap. The RIAA eq circuit on those old hi-fi amps was never particularly clever as I recall. Nor did it need to be.
> On 25 Feb 2008, "Paul Stamler" <pstamlerh...@pobox.com> > wrote in rec.audio.pro: >> Which is unfortunately awful. The OP's suggestion of an >> older stereo amplifier is a better idea. > I'm sure it's not great, but is it any worse than the > preamps built into the typicaly inexpensive stereo > receiver?
Probably. In the day of, receiver manufacturers actually put some money and care into RIAA preamps.
One indicator of potential quality might be the power supply that the preamp stages ran off of. More voltage and balanced power supplies generally meant more dynamic range, and resistance to overload. Other considerations include whether or not low-noise transistors or ICs and high-precision resistors are used where it matters.
> Or are you saying that just because it's Radio > Shack branded?
Not any real audio-related specs, just dimensions.
I'm saying that its likely that this product runs off a 12 volt or less wall-wart. That does not bode well for dynamic range. Often the transistors or IC in devices like this are pretty marginal. There are some great parts for building a low-cost RIAA preamp, but for the price, they are probably not being used.
I checked to see if this device is in a nearby RS store, but their web site found none at all, let alone near.
BTW, its analog-in, analog out which is good for your application, but not USB for those who desire a more direct connection.
> On 25 Feb 2008, "Paul Stamler" <pstamlerh...@pobox.com> wrote in > rec.audio.pro:
> > Which is unfortunately awful. The OP's suggestion of an older > > stereo amplifier is a better idea.
> I'm sure it's not great, but is it any worse than the preamps built > into the typicaly inexpensive stereo receiver? Or are you saying that > just because it's Radio Shack branded?
I'm saying it because a few years ago audioXpress published a review of several cheap preamps, and the Radio Shack unit didn't come out well. It wasn't as bad as some (several preamps had nothing close to correct RIAA response, which is inexcusable), but it wasn't that good either, and most receivers probably would do better.
Probably the most cost-effective solution would be a Hagerman preamp; they make one which is a naked PC board powered by 9V batteries that actually blew away everything else in the audioXpress tests, and it's $139, assembled. It's called the Bugle.
I have no connection with Hagerman other than having exchanged e-mails with Jim Hagerman once, about something else.
Paul Stamler <pstamlerh...@pobox.com> wrote: >"Nil" <rednoise+n...@REMOVETHIScomcast.net> wrote in message >> On 25 Feb 2008, "Paul Stamler" <pstamlerh...@pobox.com> wrote in >> rec.audio.pro:
>> > Which is unfortunately awful. The OP's suggestion of an older >> > stereo amplifier is a better idea.
>> I'm sure it's not great, but is it any worse than the preamps built >> into the typicaly inexpensive stereo receiver? Or are you saying that >> just because it's Radio Shack branded?
>I'm saying it because a few years ago audioXpress published a review of >several cheap preamps, and the Radio Shack unit didn't come out well. It >wasn't as bad as some (several preamps had nothing close to correct RIAA >response, which is inexcusable), but it wasn't that good either, and most >receivers probably would do better.
It can't be as bad as the noxious Calrad preamp, can it? The top end on that thing was so bad I though there was a tracking problem.
>Probably the most cost-effective solution would be a Hagerman preamp; they >make one which is a naked PC board powered by 9V batteries that actually >blew away everything else in the audioXpress tests, and it's $139, >assembled. It's called the Bugle.
>I have no connection with Hagerman other than having exchanged e-mails with >Jim Hagerman once, about something else.
Agreed. Or find one of the Shure standalone preamps from the seventies, which sell pretty cheaply and can drive a 600 ohm load. --scott
-- "C'est un Nagra. C'est suisse, et tres, tres precis."
>On Mon, 25 Feb 2008 09:49:03 -0600, Nil ><rednoise+n...@REMOVETHIScomcast.net> wrote:
>>> Which is unfortunately awful. The OP's suggestion of an older >>> stereo amplifier is a better idea.
>>I'm sure it's not great, but is it any worse than the preamps built >>into the typicaly inexpensive stereo receiver? Or are you saying that >>just because it's Radio Shack branded?
>I imagine it's the cheap USB a>d interface that's crap. The RIAA eq >circuit on those old hi-fi amps was never particularly clever as I >recall. Nor did it need to be.
Actually, you'd be surprised how poor the filter accuracy is on some of those preamps. A lot of that stuff is built with 10% components in the filter networks and they wind up WAY off.
In addition, there are some impulse response issues with some of the preamps that try and put both RIAA poles into the feedback loop of a single op-amp but don't have the bandwidth or open-loop gain to pull it off. I was really shocked at how much better a passive network sounded when compared with an active network in the feedback loop of a 5532. --scott -- "C'est un Nagra. C'est suisse, et tres, tres precis."
>>>> Which is unfortunately awful. The OP's suggestion of an older >>>> stereo amplifier is a better idea.
>>>I'm sure it's not great, but is it any worse than the preamps built >>>into the typicaly inexpensive stereo receiver? Or are you saying that >>>just because it's Radio Shack branded?
>>I imagine it's the cheap USB a>d interface that's crap. The RIAA eq >>circuit on those old hi-fi amps was never particularly clever as I >>recall. Nor did it need to be.
> Actually, you'd be surprised how poor the filter accuracy is on some of > those preamps. A lot of that stuff is built with 10% components in the > filter networks and they wind up WAY off.
> In addition, there are some impulse response issues with some of the > preamps that try and put both RIAA poles into the feedback loop of a > single op-amp but don't have the bandwidth or open-loop gain to pull > it off. I was really shocked at how much better a passive network > sounded when compared with an active network in the feedback loop of > a 5532.
I don't even know - do current soundcards have stereo mic-level inputs? If so, then the RIAA can be done in SW, no? -- % Randy Yates % "Watching all the days go by... %% Fuquay-Varina, NC % Who are you and who am I?" %%% 919-577-9882 % 'Mission (A World Record)', %%%% <ya...@ieee.org> % *A New World Record*, ELO http://www.digitalsignallabs.com
On 25 Feb 2008, Laurence Payne <NOSPAMlpayne1ATdsl.pipex.com> wrote in rec.audio.pro:
> I imagine it's the cheap USB a>d interface that's crap. The RIAA > eq circuit on those old hi-fi amps was never particularly clever > as I recall. Nor did it need to be.
This one has no USB interface - it's a pair of RCA connectors in, and another pair out.
> I don't even know - do current soundcards have stereo > mic-level inputs?
Very rare (if at all?) I've never seen one. (Im talking about consumer stuff like Soundblaster, etc.)
> If so, then the RIAA can be done in SW, no?
It was observed when this question was discussed last time that it is difficult-to-impossible because of the clean dynamic range that would be required in the analog end of the chain.
> "Randy Yates" wrote ... > > I don't even know - do current soundcards have stereo > > mic-level inputs?
> Very rare (if at all?) I've never seen one. > (Im talking about consumer stuff like Soundblaster, etc.)
> > If so, then the RIAA can be done in SW, no?
> It was observed when this question was discussed last > time that it is difficult-to-impossible because of the clean > dynamic range that would be required in the analog end > of the chain.
It's actually not that hard; a flat gain of 34dB, in a preamp with +/-15Vdc supplies, should do it. That'll give you a worst-case peak output of about 5V with a typical cartridge. Nominal output level will be about 0.25V for a 1kHz signal.
5V is about +16dBu; run that into a line input with nominal sensitivity of +4dBu, and you should be okay; if it clips, lower the gain on the phono preamp.
A couple of 5532s should work fine. Give each amp in the package a gain of 17db to keep the loop gain reasonable, add a coupling cap to keep out subsonics, and you should have a reasonable design.
I used to think this was a bass-ackwards way of recording. But the filters in Audition seem to be minimum-phase, the right kind for RIAA compensation, and I've heard some good results done this way. On t'other hand, you could also put an RIAA network between those opamp stages and have a perfectly fine RIAA preamp that way too.
In article <m3wsoslwgm....@ieee.org>, Randy Yates <ya...@ieee.org> wrote:
>I don't even know - do current soundcards have stereo mic-level inputs? >If so, then the RIAA can be done in SW, no?
IF you could guarantee the cartridge loading was accurate, yes. And note also that it takes a hell of a lot of gain on the front end of a mike preamp. Much more than on a typical soundcard mike input. --scott -- "C'est un Nagra. C'est suisse, et tres, tres precis."
> On t'other > hand, you could also put an RIAA network between those > opamp stages and have a perfectly fine RIAA preamp that > way too.
On the other hand, if you watch the midband gain, and don't want to drive some long lines, a half of a 5532 can get 'er done for each channel.
The open-loop gain of the 5532 (or unity-compensated 5534) is about 70 dB at 10 KHz, so as long as you make the closed loop gain less than 30 dB at 10 KHz or 24 dB at 20 KHz, there's over 40 dB feedback.
"Paul Stamler" <pstamlerh...@pobox.com> writes: > On t'other hand, you could also put an RIAA network between those > opamp stages and have a perfectly fine RIAA preamp that way too.
Yeah, if you need a preamp for gain and/or proper input loading, you might as well do the RIAA while you're at it. -- % Randy Yates % "With time with what you've learned, %% Fuquay-Varina, NC % they'll kiss the ground you walk %%% 919-577-9882 % upon." %%%% <ya...@ieee.org> % '21st Century Man', *Time*, ELO http://www.digitalsignallabs.com
> On 25 Feb 2008, "Paul Stamler" <pstamlerh...@pobox.com> wrote in > rec.audio.pro:
> > Which is unfortunately awful. The OP's suggestion of an older > > stereo amplifier is a better idea.
> I'm sure it's not great, but is it any worse than the preamps built > into the typicaly inexpensive stereo receiver? Or are you saying that > just because it's Radio Shack branded?
> The last one of these I saw the turntable was a POS.
> JAM
Compared to what and was it 's turntable or another company's?
I just finished reviewing their Tape2PC cassette deck. Not the deck isn't a Nak Dragon, but it did a nice job of letting even my wife transfer her cassettes to CD. There's a set of RCA jack on the back of the cassette deck you can use to plug in other consumer devices like a turntable preamp output.
Paul: Is this ground wire a safety issue or a sound issue? I see the ground connection on the back of the amp, but I don't have the wire. Can I get one at Radio Shack or can I fashion something some paperclips, etc?
TS
On Feb 25, 3:15 am, "Paul Stamler" <pstamlerh...@pobox.com> wrote:
> > I know I can boost the sound on the audio in Audacity (or any audio > > software) but there is a lot of hiss so I'm not sure this will produce > > a nice recording. I guess to ask the question is to answer it, but > > should I be connecting the turntable into a stereo amplifier and then > > the amplifier into the computer?
> Yes. Use a dual-RCA > mini-stereo cable, and connect the RCAs to the tape > outputs of your stereo amplifier, and the mini-stereo to the LINE input of > your computer. Connect the turntable to the phono input of the amplifier, > and don't forget to hook up the ground wire.
>On Feb 25, 3:15 am, "Paul Stamler" <pstamlerh...@pobox.com> wrote: >> Yes. Use a dual-RCA > mini-stereo cable, and connect the RCAs to the tape >> outputs of your stereo amplifier, and the mini-stereo to the LINE input of >> your computer. Connect the turntable to the phono input of the amplifier, >> and don't forget to hook up the ground wire.On Sat, 1 Mar 2008 16:17:41 -0800 (PST), Thumper <thumperstra...@gmail.com> wrote: >Paul: Is this ground wire a safety issue or a sound issue? I see the >ground connection on the back of the amp, but I don't have the wire. >Can I get one at Radio Shack or can I fashion something some >paperclips, etc?
I'm certainly not Paul, but assuming that he has a life on Saturday night, and knowing that I'm home listening to Garrison on PHC instead of accepting the invitation to the tight-200-seat production of an uplifting, politically conscious, this- weekend-only show, probably post-feminist but not post-modern, please allow me to comment....
But seriously, the ground wire Paul mentioned is for signal and not for safety. The best possible grounding is to have everything separate - signal grounds all run around by themselves and never touch any others, until the last possible opportunity.
At phono signal levels, this can become a *possible* issue, but isn't a deal-killer. So, if your turntable doesn't have a separate ground wire, the chassis ground is being carried on one of the signal grounds. If it *does* have a wire, connect it; otherwise, no prob.
All good fortune,
Chris Hornbeck "It's 90% boilerplate, 1% real work, 9% WTF?" -Les Cargill
> Paul: Is this ground wire a safety issue or a sound issue? I see the > ground connection on the back of the amp, but I don't have the wire. > Can I get one at Radio Shack or can I fashion something some > paperclips, etc?
Mostly sound; the amp will buzz if the ground wire's not connected. But there may be safety issues too.
Usually a turntable will come with a ground wire attached, in addition to the stereo signal cable. (Sometimes the signal and ground wires are a single unit; look for a loose wire with maybe a spade lug on it in the signal-cable bundle.) It's typically connected to something on the tonearm, but it might be on the turntable frame. If necessary, rig something with a length of wire and a clip-lead: connect the wire to the ground terminal on the amp. On the other end, attach a clip-lead, connect the audio cables, plug in both the turntable and the amp to the walls, turn the amp on and set it to phono. You'll hear a hashy buzz; start clipping the clip-lead to the turntable frame until you find a place that stops the buzzing without interfering with the arm's movement.
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