During the early 80s when the Apt line was actually new gear. It was prominently displayed in our showroom.
I do remember some folks using the tone controls on the Apt Preamp. But for the most part, most all of them would return them to thier neutral position or use the tone control defeat switch to get them out of the circuit.
Most who did use them, liked then when listening to contemporary rock n roll of that era. But jazz and classical users never did use the tone controls.
The Apt, if memory serves me correct was the only preamp we sold that had tone controls. As far as graphic equalizers go we never sold them. At the time we found that equalizers injected more noise into a system, than the overall benefit provided and
most of our customers agreed, during the audition. We kept one equalizer for demo use, I think it was a Technics 5 band, though I could be wrong there.
The Apt line was great, and sold a lot of it and many of my customers still have that gear, although I closed the store some years ago. Still keep in touch with some of them.
As far as this thread goes, in regards to tone controls, I prefer a preamp with the least amount circuitry needed to reproduce the musical signal and with Class A operation throughout.
Whether tone controls are a useful feature is in the hands of the end user. As for me I have never found them useful.
A LP or CD that was off recorded and needs tonal embellishment to listen to, does not have a place in my library.
I do remember some folks using the tone controls on the Apt Preamp. But for the most part, most all of them would return them to thier neutral position or use the tone control defeat switch to get them out of the circuit.
Most who did use them, liked then when listening to contemporary rock n roll of that era. But jazz and classical users never did use the tone controls.
The Apt, if memory serves me correct was the only preamp we sold that had tone controls. As far as graphic equalizers go we never sold them. At the time we found that equalizers injected more noise into a system, than the overall benefit provided and
most of our customers agreed, during the audition. We kept one equalizer for demo use, I think it was a Technics 5 band, though I could be wrong there.
The Apt line was great, and sold a lot of it and many of my customers still have that gear, although I closed the store some years ago. Still keep in touch with some of them.
As far as this thread goes, in regards to tone controls, I prefer a preamp with the least amount circuitry needed to reproduce the musical signal and with Class A operation throughout.
Whether tone controls are a useful feature is in the hands of the end user. As for me I have never found them useful.
A LP or CD that was off recorded and needs tonal embellishment to listen to, does not have a place in my library.
On many equipments, tone controls can usually be bypassed but they are not easily retrofittable in equipement lacking them. I only remember DB Systems as having a dedicated tone control in the collection of their nice little boxes.
I own a parametric equalizer where frequencies, levels and Qs can be adjuted, I rarely use it. However I have simple bass and treble controls in some of my integrated amplifiers and in my two cars. Full control (button seven or five o'clock) could give about 10 dB cut or boost. I spent quite a lot of time to adjust them to slighlty correct the overall room or car volume rendition for the best pleasure of my ears. They were never left at more than 10 or 2 o'clock. Once set, I do not touch them often.
For very long, I did not have tone controls, amplification was straight. I think this was an error. Since the publication of Holman's article (which has been translated in french in 1978) , I have always found it was a major piece for audio thinking. Thanks to the internet, I got the Holman tone controls schematics last year. Having learned a bit how to simulate, I could see what were the obtainable curves and I designed a Baxandall version with the same bass turnover frequency, but with less maximum cut/boost, 10 dB being largely sufficient.
~~~~~~~~ Forr
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I own a parametric equalizer where frequencies, levels and Qs can be adjuted, I rarely use it. However I have simple bass and treble controls in some of my integrated amplifiers and in my two cars. Full control (button seven or five o'clock) could give about 10 dB cut or boost. I spent quite a lot of time to adjust them to slighlty correct the overall room or car volume rendition for the best pleasure of my ears. They were never left at more than 10 or 2 o'clock. Once set, I do not touch them often.
For very long, I did not have tone controls, amplification was straight. I think this was an error. Since the publication of Holman's article (which has been translated in french in 1978) , I have always found it was a major piece for audio thinking. Thanks to the internet, I got the Holman tone controls schematics last year. Having learned a bit how to simulate, I could see what were the obtainable curves and I designed a Baxandall version with the same bass turnover frequency, but with less maximum cut/boost, 10 dB being largely sufficient.
~~~~~~~~ Forr
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Perreaux of New Zealand did make a separate tone control component.
Link Below.
http://www.perreaux.com/files/039-TC2.pdf
Had one of those once we got in on trade, but never got around to using it. At least this is a separate component and can be totally switched out or turned off ,if so desired.
So if someone wants to add tone controls to a preamp without them, here is an alternative.
Link Below.
http://www.perreaux.com/files/039-TC2.pdf
Had one of those once we got in on trade, but never got around to using it. At least this is a separate component and can be totally switched out or turned off ,if so desired.
So if someone wants to add tone controls to a preamp without them, here is an alternative.
burnedfingers said:
The power amp is better than the preamp. The pre-amp sucks sonically (in its day it was OK) -- i've always wondered where it would go with a real power supply and replacement of the TL072s.
I've owned multiples of both.
I have the pre-amp manual -- all schem & board layouts included. I'm surprised i don't have at least a power amp schema (it comes attached to the bottom of the amp)
dave
planet10 said:
IS there a drop in replacement for TL072 (or a near drop in)? I have a apt pre that I've been wanting to tweak for awhile now.
rif said:
I'm not all that familiar with SS. I have a lot of OPA2134 which seems compatible (i'd double check with the experts 1st) so that is likely what i'd try.
The existing ICs are best replaced with sockets 1st... there are quite a few
dave
Hi Rif, Planet10,
The same curves than those of the Holman tone control can be replicated with a simple Baxandall virtual earth circuit. Keeping the same circuit and only changing the op-amps is not a serious upgrade.
Hi Yeoldestereo.
Nice box, this Perreaux tone control. I think it was never sold in Europe.
Any specs and/or schematics ?
~~~~~~~~~ Forr
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The same curves than those of the Holman tone control can be replicated with a simple Baxandall virtual earth circuit. Keeping the same circuit and only changing the op-amps is not a serious upgrade.
Hi Yeoldestereo.
Nice box, this Perreaux tone control. I think it was never sold in Europe.
Any specs and/or schematics ?
~~~~~~~~~ Forr
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Dont' have specifications on the Perreaux Tone Control unit.
However from time to time they come up on eBay and Audiogon and usually sell for $150.00 to $200.00 USD sometimes less.
Not sure of European distribution. Just would depend if Perreaux had a distributor in Europe in the early 80s.
However from time to time they come up on eBay and Audiogon and usually sell for $150.00 to $200.00 USD sometimes less.
Not sure of European distribution. Just would depend if Perreaux had a distributor in Europe in the early 80s.
yeoldestereo said:
You mean a distributor in every European country.
Perreaux still offered a preamp with tone control in the late 80s, the $2k SA33 model. The TC2 was not sold here, tone control was not considered audio grade then either.
Thanks for the info.
Was not aware of the SA 33, in fact never have seen the unit.
Perreaux having a tough time in U.S. in keeping a distributor,right now I think the U.S. distribution is suspended once again.
Link to SA 33 Below
http://www.perreaux.com/files/055-SA33.pdf
Once again many thanks for the update.
Was not aware of the SA 33, in fact never have seen the unit.
Perreaux having a tough time in U.S. in keeping a distributor,right now I think the U.S. distribution is suspended once again.
Link to SA 33 Below
http://www.perreaux.com/files/055-SA33.pdf
Once again many thanks for the update.
preamp manual
Note that it is 7.6 MB. Worth the download just to see what a really well done manual looks like.
dave
Note that it is 7.6 MB. Worth the download just to see what a really well done manual looks like.
dave
Thanks Dimitri,
With the preamp manual yesterday, it's a real good start for 2006.
What else tomorow ? I am looking for Jon Iverson amplifiers and Robertson (not Mikeks's) amplifiers...
~~~~~~ Forr
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With the preamp manual yesterday, it's a real good start for 2006.
What else tomorow ? I am looking for Jon Iverson amplifiers and Robertson (not Mikeks's) amplifiers...
~~~~~~ Forr
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planet10 and dimtri:
thanks for posting the manuals! i especially enjoyed the preamp manual - that one appears to be more recent than my paper version i got from apt so many years ago. my version didn't include the test setups and other items in the last several pages.
yep, they definately don't make manuals like this anymore.
too bad ...
mlloyd1
thanks for posting the manuals! i especially enjoyed the preamp manual - that one appears to be more recent than my paper version i got from apt so many years ago. my version didn't include the test setups and other items in the last several pages.
yep, they definately don't make manuals like this anymore.
too bad ...
mlloyd1
Re: Re: Re: APT 1 power amp – undeservedly forgotten
Not moi...!!
Thank Planet10 & dimitri..! 🙂
Correct... 🙂
bremen nacht said:
Not moi...!!
Thank Planet10 & dimitri..! 🙂
forr said:
Correct... 🙂
Mlloyd1
"thanks for posting the manuals! i especially enjoyed the preamp manual - that one appears to be more recent than my paper version i got from apt so many years ago. my version didn't include the test setups and other items in the last several pages.
yep, they definately don't make manuals like this anymore.
too bad ..."
I think you are the person who sent me a short version last year. Thanks again. I've been interested by the Holman preamp schematics since twenty five years because it was a preamp with tone control designed with a lot of thinking behind, not just of copy of other products.
Dave
"It is more like they never made manuals like that very often anytime."
An old idea of mine would be to create a new job : manuals writer, who could work for many companies. He/she could even make the companies to modify the command interface of their product to make them more user-friendly.
~~~~~ Forr
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"thanks for posting the manuals! i especially enjoyed the preamp manual - that one appears to be more recent than my paper version i got from apt so many years ago. my version didn't include the test setups and other items in the last several pages.
yep, they definately don't make manuals like this anymore.
too bad ..."
I think you are the person who sent me a short version last year. Thanks again. I've been interested by the Holman preamp schematics since twenty five years because it was a preamp with tone control designed with a lot of thinking behind, not just of copy of other products.
Dave
"It is more like they never made manuals like that very often anytime."
An old idea of mine would be to create a new job : manuals writer, who could work for many companies. He/she could even make the companies to modify the command interface of their product to make them more user-friendly.
~~~~~ Forr
§§§