I've got an ARC LS3 preamp paired with a P5Pro Dartzeel 108B clone power amp. It is an amazing combo. I bought the Cary SLP90 clone tube preamp (as per Hifi Zone's recommendation on Youtube) with the Dartzeel.
Can someone knowledgeable in these things explain why this 30 yo ARC preamp performs so well and dominates this tube amp which is famous for 3D soundstage?
Furthermore, how hard would it be to overhaul the ARC LS3? I've been quoted silly prices. Can a newbie do it himself?
Lastly, are there any sub $1k preamps that perform like an ARC line stage? Chifi clone or otherwise? It may not be economical to recap the LS3 and I need a plan B...
Many thanks!
Can someone knowledgeable in these things explain why this 30 yo ARC preamp performs so well and dominates this tube amp which is famous for 3D soundstage?
Furthermore, how hard would it be to overhaul the ARC LS3? I've been quoted silly prices. Can a newbie do it himself?
Lastly, are there any sub $1k preamps that perform like an ARC line stage? Chifi clone or otherwise? It may not be economical to recap the LS3 and I need a plan B...
Many thanks!
Why would you want to do any work on the preamp if it sounds so good?
And what if it does not sound as good (or function at all) after working on it? This happens rather frequently.
And what if it does not sound as good (or function at all) after working on it? This happens rather frequently.
The tracks on the board are corroded and it has lived a rough life. At 30 years of age I was under the impression these things need overhauling. At least to do some preemptive work to reduce the likelihood of a catastrophic failure
You ask how hard it would be to do an overhaul.
You say it's to expensive for a skilled person to do this.
Then that it has corroded tracks..
Pardon me for being blunt but.
Before you do anything to it that will make some of us cry.
Sell it, and buy a new something else under your $1,000.00 search.
I've seen and repaired the damage of the 'well intentioned and unskilled'.
It makes the labour costs skyrocket because I have to undo the carnage before I can put it together, Then fix whatever issues it has inherited.
You say it's to expensive for a skilled person to do this.
Then that it has corroded tracks..
Pardon me for being blunt but.
Before you do anything to it that will make some of us cry.
Sell it, and buy a new something else under your $1,000.00 search.
I've seen and repaired the damage of the 'well intentioned and unskilled'.
It makes the labour costs skyrocket because I have to undo the carnage before I can put it together, Then fix whatever issues it has inherited.
Thanks, I value the blunt feedback. Still curious why this 30 year solid state tech performs so well. Maybe it's the ARC touch
Well, this is kinda what this forum's all about, this thread is worth going through to get the principals of what we've all been working with for the last century of recorded sound. There are some robust perspectives regarding the concepts, the circuit topologies, their implementation, all intertwined with perception of numerous audible characteristics and how we reference these and how we communicate them:-
(https://www.diyaudio.com/community/threads/antique-gear.419911/)
" how hard would it be to overhaul the ARC LS3? I've been quoted silly prices. Can a newbie do it himself?"
I would suggest that the Audio Research Line Stage 3 preamp is definitely not for the beginner to overhaul.
That said if it is one of these-
it appears that there are only three electrolytic capacitors in the power supply that should probably be replaced, fairly straight forward,
IF you have good mechanics dismantling and reassembly skills, good soldering skills and methodical patience.
There are good film caps in there, they tend not to deteriorate and remain stable. Looks like a minimalist layout too, that's always good for audio.
I would check if there are functional errors present, If it ain't broke dont fix it!
Were it my machine to service:
The front panel would be removed sequentially, dismantled, servicing all potentiometers, switches replacing anything thats not functioning to specification. Cleaning the entire PCB and do careful track re-soldering.
Replacing all electrolytics caps, like for like or for e.g.: Panasoninc FM's/ FR's
Check/ replace regulators and any components that run hot by design, along with any semiconductors/ components that look heat stressed.
This is the part that you would need to find some one that is either capable of calibratiing the machine, as it is often whether or not you can obtain a service manual and whether or not it has the calibration settings procedure or if Audio Research will offer such data. Or find a specialist familiar with that type of pre amp, as all audio electronics have their own particular characteristics of degradation. A seasoned pro will know where to go and what to look for quickly, and thats what your paying for.
Do Audio Research still service their own legacy products? Find out, send it to them, get an equivalent Carnet to pass customs.
I would suggest that the Audio Research Line Stage 3 preamp is definitely not for the beginner to overhaul.
That said if it is one of these-
it appears that there are only three electrolytic capacitors in the power supply that should probably be replaced, fairly straight forward,
IF you have good mechanics dismantling and reassembly skills, good soldering skills and methodical patience.
There are good film caps in there, they tend not to deteriorate and remain stable. Looks like a minimalist layout too, that's always good for audio.
I would check if there are functional errors present, If it ain't broke dont fix it!
Were it my machine to service:
The front panel would be removed sequentially, dismantled, servicing all potentiometers, switches replacing anything thats not functioning to specification. Cleaning the entire PCB and do careful track re-soldering.
Replacing all electrolytics caps, like for like or for e.g.: Panasoninc FM's/ FR's
Check/ replace regulators and any components that run hot by design, along with any semiconductors/ components that look heat stressed.
This is the part that you would need to find some one that is either capable of calibratiing the machine, as it is often whether or not you can obtain a service manual and whether or not it has the calibration settings procedure or if Audio Research will offer such data. Or find a specialist familiar with that type of pre amp, as all audio electronics have their own particular characteristics of degradation. A seasoned pro will know where to go and what to look for quickly, and thats what your paying for.
Do Audio Research still service their own legacy products? Find out, send it to them, get an equivalent Carnet to pass customs.
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Yes, you might say that it's the ARC touch, but it's more correct to say that it's more thanks to ARC's knowledge and legacy in tubes.
LS3 have 270 Volt powersupply and are built pretty much as a single ended tube preamp but with J-fets and Mosfets.
Basically a transistor version of a tube preamp.
Low gain differential input stage with a single ended VAS and Mosfet buffer.
Very good engineering and single ended, non complementary VAS stages will have a very ear pleasing harmonic distortion characteristic where 2nd harmonic is slightly higher that 3rd. I say it's a very clever design that are highly dynamic and musical because of the high voltage power supply and single ended VAS.
There are several other transistor preamps from ARC that are absolutely amazing.
Personally I have a LS12 and I will never part with it.
I know that Conrad-Johnson design some nice transistor preamps with a similar basic concept.
They also take great care about distortion and distortion characteristics as a way to tune their products to their satisfaction.
Have only owned and heard their tube preamps though.
Latest was a LS-17 that was very good.
Back in the day, I bought the Audio Research LS3 preamp after I saw the infamous Stereophile "Class A" rating, which was a decent solid state preamp but nothing extraordinary. Simple shunt resistor volume control "preamp" easily surpassed it in sound quality...
Well, not much that can beat two resistors in the signal path when it comes to sound quality, but when you need the amplification that a active preamp can provide, then LS3 is a very good preamp for the money.
A shunt resistor volume control are more likely to restrict your choices of suitable power amplifier.
A shunt resistor volume control are more likely to restrict your choices of suitable power amplifier.
No, not a hybrid.
Sorry if I pointed in wrong direction with me calling it LS-17.
Looked it up and the correct name is Premier Seventeen LS or Premier 17LS.
There is only one gain stage consisting of 4 pcs of parallelled 6922. No buffers and no cathode followers. Zout=850 ohm.
Power supply is, if I remember right a darlington configuration controlled by a current source loaded zener sting.
So no active regulation in the power supply and only high quality film or metalized film polypropylene capacitors.
Very high quality of all components and a overall a very good sound with outstanding musicality because of the
designers choice to not remove even harmonic distortion.
https://www.stereophile.com/tubepreamps/370/index.html
Sorry if I pointed in wrong direction with me calling it LS-17.
Looked it up and the correct name is Premier Seventeen LS or Premier 17LS.
There is only one gain stage consisting of 4 pcs of parallelled 6922. No buffers and no cathode followers. Zout=850 ohm.
Power supply is, if I remember right a darlington configuration controlled by a current source loaded zener sting.
So no active regulation in the power supply and only high quality film or metalized film polypropylene capacitors.
Very high quality of all components and a overall a very good sound with outstanding musicality because of the
designers choice to not remove even harmonic distortion.
https://www.stereophile.com/tubepreamps/370/index.html
imho the failure of audio research is also because their rich Pres have a low quality/price ratio due to the use of integrated circuits for volume control... if they used relay volume they sounded better.
I'm under the impression the ARC guys did something really right with their tube gears, and have been chasing their qualities with sand since forever.
You've been given some good advise worth repeating: unless you're a seasoned hot-rodder, stand well clear. Desoldering metalized holes PCB takes at less a dozen tries (and destructions) to get right. And that's long before you tackle the black magic of audio circuit design.
With that said, if this were mine, I'd bypass entirely the PCB based input wiring. In stead, I'd use relay switching at the back and good quality wiring to the front. With very careful planning, this could be made reversible.
You've been given some good advise worth repeating: unless you're a seasoned hot-rodder, stand well clear. Desoldering metalized holes PCB takes at less a dozen tries (and destructions) to get right. And that's long before you tackle the black magic of audio circuit design.
With that said, if this were mine, I'd bypass entirely the PCB based input wiring. In stead, I'd use relay switching at the back and good quality wiring to the front. With very careful planning, this could be made reversible.
...an easy mistake to make!
I thought you may be mentioning the Audio Research LS17 Hybrid JFET/tube audio circuit, with the solid-state power supply.
I know of another DIY preamp that behaves like this. It is the Stereo Coffee LDR (Light Dependent Resistor). They get rave reviews on StereoNet.
Forgive my lack of knowledge on how these work - can you tell whether the creator is achieving a similar effect to the Audio Research Pre in his design? It would be a far cheaper way to get similar performance to the ARC.
https://stereocoffee.wixsite.com/ldrpreamp/the-ldr-kit-details
No, I can not tell for sure, because I have no experience from Stereo Coffee LDR.
But don't you think LDR resistors would be more used in many other applications within audio if it was superior to a relay or a potentiometer?
LDR is not a new technology and is mostly common in the D.I.Y. community where some enthusiastic "inventors" claim superiority.
So I have my doubts based on how well this technology have penetrated the audio market, but admittely need to hear one to have a solid opinion.
I have built a few passive preamps over the years with different technologies and they all where different in sound character.
Liked the Sowter transformer attenuator I once built a lot, but in general they lack the energy, soundstage and dynamics a good active preamp have.
Personally I would not go the passive route again.
But don't you think LDR resistors would be more used in many other applications within audio if it was superior to a relay or a potentiometer?
LDR is not a new technology and is mostly common in the D.I.Y. community where some enthusiastic "inventors" claim superiority.
So I have my doubts based on how well this technology have penetrated the audio market, but admittely need to hear one to have a solid opinion.
I have built a few passive preamps over the years with different technologies and they all where different in sound character.
Liked the Sowter transformer attenuator I once built a lot, but in general they lack the energy, soundstage and dynamics a good active preamp have.
Personally I would not go the passive route again.