Is anyone familar with this RIAA amp, published by Hi Fi News and Revord Review in the 80's?
I would like to see the schematics if possible.
I recall he also had a passive amp in this series.
Tom
EE
I would like to see the schematics if possible.
I recall he also had a passive amp in this series.
Tom
EE
This designation is similar to the Analog Devices AMP01.
Did Ben Duncan use these ICs?
Would instrumentation op amps work well for the MM type cartridges?
Tom
EE
Did Ben Duncan use these ICs?
Would instrumentation op amps work well for the MM type cartridges?
Tom
EE
tmblack said:
Hi,
Audio Synthesis, www.audiosynthesis.co.uk supplies bound reprints of the AMP01 and AMP02 series of articles. I bought them a few years back. Don't see them listed on the website but may still be available.
James
I would buy the reprint but its no longer available.
its been a long time and I need to refresh my memory.
How does the amp 02 differ from the amp 01?
What chips do they use?
Thanks
Tom
EE
its been a long time and I need to refresh my memory.
How does the amp 02 differ from the amp 01?
What chips do they use?
Thanks
Tom
EE
Hi,
Ben D. used opamps that seemed to be just reaching the market at that time. All VERY expensive.
By now most of these will be a lot cheaper both in actual cost and in real terms. I suspect a few of them can be replaced with better more modern alternatives.
Have you tried the library archive?
Ben D. used opamps that seemed to be just reaching the market at that time. All VERY expensive.
By now most of these will be a lot cheaper both in actual cost and in real terms. I suspect a few of them can be replaced with better more modern alternatives.
Have you tried the library archive?
No libraries around here carry issues that far back.
But I just need to know the topography used.
Was it a 2 op amp passive design?
Tom
EE
But I just need to know the topography used.
Was it a 2 op amp passive design?
Tom
EE
Hi Tom,
The amp 01 is a 3 ic design with mixed active/passive riaa eq. It has/had switched gain to cater for mc and mm carts as well as an option for balanced/unbalanced input. PM me if you want more info on his amp 02 and passive pre articles.
Cheers,
Steve.
The amp 01 is a 3 ic design with mixed active/passive riaa eq. It has/had switched gain to cater for mc and mm carts as well as an option for balanced/unbalanced input. PM me if you want more info on his amp 02 and passive pre articles.
Cheers,
Steve.
tmblack said:
If you know the issue in question you can order it from the Document Supply Centre in Boston Spa via your local library.
In London, The Science Museum library and the British Library both carry back issues of HFNRR going back to at least the 70's. The IEEE library might also carry it.
BTW, If you want to build the AMP02 phono stage tracking down the SSM2016 might prove tricky.
The SSM2019 should work well in place of the SSM2016, but I'm more interested in his reasoning than actually cloning the circuit.
IC's are much better and cheaper than in those days.
Tom
EE
IC's are much better and cheaper than in those days.
Tom
EE
I doubt this helps but here's some info about Ben Duncan's riaa-equalisation module.
http://mail.google.com/mail/?view=att&disp=inline&attid=0.1&th=10265c6d0caedd8d
PS I have a little more information,if only I could find it !
http://mail.google.com/mail/?view=att&disp=inline&attid=0.1&th=10265c6d0caedd8d
PS I have a little more information,if only I could find it !
I don't know about the AMP01 but I built the AMP02 many years ago.
It had an error on the pcb whiich caused dc offset at the o/p of the SSM2016, although even when this was corrected the sound was not great.
The SSM2017 actually sounds better than the 2016 and is much easier to apply.
I have full set of AMP02 articles but would not recommend expending any effort on this project - there are many better sounding and much simpler RIAA stages around.
Dave
It had an error on the pcb whiich caused dc offset at the o/p of the SSM2016, although even when this was corrected the sound was not great.
The SSM2017 actually sounds better than the 2016 and is much easier to apply.
I have full set of AMP02 articles but would not recommend expending any effort on this project - there are many better sounding and much simpler RIAA stages around.
Dave
Hello Dave,
I was intrigued by the balanced input which might help with hum.
Which circuits do you like better?
Tom
EE
I was intrigued by the balanced input which might help with hum.
Which circuits do you like better?
Tom
EE
Hi Tom,
The AMP02 sounded better when the 2016 was replaced by a 2017. AD845 is also not one of my favourite opamps.
Unfortunately I used silver plated ptfe wire (before I knew better)for the balanced tonearm cable with my Amp02 - this gave a rather bright and spitty sound quality. Reverting to a "normal" arm cable in unbalanced mode gave much better results and hum was never an issue anyway (why try to solve a problem that does not exist?).
A JLH discrete RIAA stage sounded better that the AMP02 (and very similar to a Linn Kairn phono stage). In fact any competently designed 2 or 3 stage phono amp using decent opamps (e.g. AD797, OP27/37 or even NE5534 ) sounds better that the AMP02 IMHO.
What to build instead?
I'm not sure - I rarely listen to records nowadays. Maybe best to look for recommendations from somebody like Werner.
Cheers,
Dave
The AMP02 sounded better when the 2016 was replaced by a 2017. AD845 is also not one of my favourite opamps.
Unfortunately I used silver plated ptfe wire (before I knew better)for the balanced tonearm cable with my Amp02 - this gave a rather bright and spitty sound quality. Reverting to a "normal" arm cable in unbalanced mode gave much better results and hum was never an issue anyway (why try to solve a problem that does not exist?).
A JLH discrete RIAA stage sounded better that the AMP02 (and very similar to a Linn Kairn phono stage). In fact any competently designed 2 or 3 stage phono amp using decent opamps (e.g. AD797, OP27/37 or even NE5534 ) sounds better that the AMP02 IMHO.
What to build instead?
I'm not sure - I rarely listen to records nowadays. Maybe best to look for recommendations from somebody like Werner.
Cheers,
Dave
Is it understood why silver plated ptfe wire gives this sound quality?
How do you ground your tonearm?
Several players I have savaged have horrible hum, like an old Thoren.
Tom
EE
How do you ground your tonearm?
Several players I have savaged have horrible hum, like an old Thoren.
Tom
EE
In case it can help, I still havef many of Duncan's articles published in Hifi-News.
~~~~~~~~ Forr
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~~~~~~~~ Forr
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Revisiting the Amp-02 ADEQ......
I've had my ADEQ having built it at the time of the original issue, and have enjoyed it greatly. Ive had to revisit setting it up due to a cartridge change, and am interested to read Dave S's comments of a PCB error of which i was not aware - If you are still about here can you let me know of the error details?. While its apart I would d like to correct it while setting the gain for the the new cart.
I've aways been happy with mine, using it as the phono stage for a pair of Leak TL25's with a simple volume control pot on the output as detailed in the construction notes.
Chris C
I've had my ADEQ having built it at the time of the original issue, and have enjoyed it greatly. Ive had to revisit setting it up due to a cartridge change, and am interested to read Dave S's comments of a PCB error of which i was not aware - If you are still about here can you let me know of the error details?. While its apart I would d like to correct it while setting the gain for the the new cart.
I've aways been happy with mine, using it as the phono stage for a pair of Leak TL25's with a simple volume control pot on the output as detailed in the construction notes.
Chris C
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