C46 Preamplifier--Help me make the right call...

[c_dk]

I believe elstat's mentor, hero (and sometimes baker) had as a early pronouncement that most exceptional recordings were poor performances, excellent performances were most often poor recordings.......so he would regularly review and publish his list of exceptional recordings with exceptional performances.

I would guess that in that case a passive volume control is all that is needed to control gain.

But how about the vast majority of great music recorded badly.......for the music lover not the golden ear gear junkie, a control center that allows the user to correct the faulty recording is a great asset and the user that McIntosh counted on as a customer.

The mere fact that the Signetics op amps dropped in price from a $4.50 wholesale price in the 70s to the less than a buck price today only shows how their excellent performance has lasted the test of time and created a whole crop of imitators and want to be's.

And those of us with inquiring minds and a diagonal cutter know well what was inside those blocks of plastic that so many esoteric companies used to hide their top secret circuits.

There can be multiple views on these subjective audio subjects.......

 

[kevzep]

In all the McIntosh pre-amplifiers I have heard, or any high end pre for that matter including mixing consoles (which is a lot since its my job), I have not heard any evidence that OP amps with high feedback degrade signals, on the contrary, lower distortion, lower noise floor are some of the benefits in my experience, this allows more resolution in the source.
I guess McIntosh stick with these designs because over the years they have been successful and popular.

The iconic Neve 80 series consoles were not class A, they used high current discrete OP amps which allows more headroom, lower distortion than class A, the magic was in the EQ amp in those 80 series consoles, class A runs too hot, and draws too much current and has poor overload recovery which is incredibly important in the world of professional recording.
Most proper serious recording studios with Neve's have power conditioners to stabilise the AC line as Neve's are very sensitive to the condition of the AC line they are running off of.

Everybody likes different things and that is all good!! But just because you have your own preference, it doesn't make it law, we are just a bunch of guys listening to gear we like, I am lucky enough to make a living from it, but that doesn't make what I say law either, but since I spend a lot of my life listening to gear, I have developed a high level of critical listening ability, so I know what I hear.

 

[E-Stat]

The iconic Neve 80 series consoles were not class A, they used high current discrete OP amps which allows more headroom,...

But is the case with his “culmination” model 5088 to which I previously linked. Just read the first paragraph.

 

[c_dk]

Back in college it drove me crazy when certain professors would use the term "elegant" to describe a certain design or process but I guess when the design deserves it...... the EQ circuit mac started using with the MAC4100 receiver was a "elegant" EQ circuit.......audio does not pass thru 5 ICs but only the 2 that are used as summation devices.....so if your EQ controls are at neutral no altering of the feedback of the summation devices is made.

And lets face it the 5532 and 5534 ICs from Signetics have set a high bar that has spurned on a whole collection of "improved" ICs from all the major semiconductor makers as well as some high flying startups. They still are considered a benchmark device.

 

[kevzep]

But not true of his “culmination” model 5088 to which I previously linked. Just read the first paragraph.

and then the next design was not class A.

Good chat, I'm off to work now, ears are packed, OP amps everywhere, good times.

 

[c_dk]

Just make sure the "talent" sounds class A.

 

[MACKIE1975]

Yamaha M7CL anytime

 

[E-Stat]

Good chat, I'm off to work now...

Yep.

Hmmm. The class A based 5088 is the current one found on his website touted as the “culmination” product. Kindly link to the “next design” for my reference.

Thanks!

Looking at the C1000P schematic, it appears the active circuitry used discrete JFETs. And the current C1100 statement product uses discrete triodes. Go figure...

 

[quartersaw]

Believe me, I'm the last one to obsess over specs as it relates to performance - - I merely thought the comparison was interesting.

FWIW - they are McIntosh's numbers after all...

I think as old preamps are replaced with newer units, the new purchase sounds 'better' because it has fresh components.
My C-35's have 105Db S/N, and .002% distortion.When I refresh the internals this year, I would wager that they will sound as good as a number of 'new' Mcintosh Pre's

 

[62caddy]

I think as old preamps are replaced with newer units, the new purchase sounds 'better' because it has fresh components.
My C-35's have 105Db S/N, and .002% distortion.When I refresh the internals this year, I would wager that they will sound as good as a number of 'new' Mcintosh Pre's

It may well do that already!

 

[PanheadXR290]

I think as old preamps are replaced with newer units, the new purchase sounds 'better' because it has fresh components.
My C-35's have 105Db S/N, and .002% distortion.When I refresh the internals this year, I would wager that they will sound as good as a number of 'new' Mcintosh Pre's

As long as everything is functioning properly I've found that even my super old C-26 I bought strictly for vintage 3 channel recordings sounds very McIntosh house sound and up to date .

Many owners of their "Flagship" pre-amp will be using outboard Room EQ - such as the McIntosh MEN220 - which is the mother of all tone controls.

You'll see that Mac includes the MEN220 in the list of components comprising their "Reference System."

Providing exotic tone controls by way of a separate component fit's with the same groundless high-end notions of "separating everything" as having separate power amp, pre-amp, phono pre-amp, CD-Transport, DAC, and so on and so one. Many of these can be combined with ZERO audible impact but are not b/c audiophiles want to have a pile of components and hi-fi mfgs are happy to oblige.

Having separates vs intergrated/receivers is not a manufacturers ploy ,or a need strictly driven by audiophiles desire for asthetics ,if we all had highly efficient speaker systems and listened at low to moderate SPL levels than intergrated amps are fine,for those of us who listen at high SPL levels ,have inefficient 4 ohm speaker systems ,and listen to demanding material such as rock,heavy metal & orchestral ,the need for separate amplification becomes clear mathematics.

An 84 db efficient speaker " many of us have " requires roughly 400 watts of amplification to produce the same SPL levels as a 90 db speaker driven with 100 watts,or a 100 db speaker system driven with 10 watts ,it's not HiFi mag drool that dictates the doubeling of SPL requires a 10x increase in wattage ,to even hear a difference we need a 3db increase ,then we have recordings which have transients that double the continuous SPL and require 10x the wattage to accurately reproduce ,those of us with McIntosh line arrays & other inefficient speaker systems would not hear the transient peaks in rock or heavy metal ,or the transient waves that are common in orchestral pieces with heavy percussion runs and creshendos ,these transients are not unimportant issues either ,they are very serious musical cues that allow listeners to hear the attack of percussion ,without those musical cues recordings sound lifeless like so many modern pop recordings that have had the mix f-ed with to make the song appear to play louder .

There are very few intergrated amps made that can properly drive my 8 ohm 87 db McIntosh XRT-22s ,even less are made that are able to properly drive the 8 ohm 87 db McIntosh XR-290s I gave to my brother a few months back ,and not a single intergrated is made that I know of that can properly drive my 4 ohm 88 db McIntosh XRT-28s that don't even come alive with less than half their rated 1,200 watts put to them .

Last we have the issue of power supplies ,sharing the same power supply influences specs like Crosstalk ,noise floor ,available headroom etc , even the Marshall JMP-1 preamp section and 9200 single chasis dual monoblock amp I use to drive my guitar rig has separate power supply for all 3 functions ,each monoblock within the single chasis has it's own power supply and it's own power cord ,3 power cords where the " normal " head amps used contain a single power supply & power cord to drive 2 channels and the preamp section ,the amp I use in my guitar rig is a studio amp designed for studio use ,audio engineers aren't concerned with audio magazine drool about chocolatey mids and dreamy caramel highs ,when designing studios they look at performance .

 

[ODS123]

Having separates vs intergrated/receivers is not a manufacturers ploy ,or a need strictly driven by audiophiles desire for asthetics ,if we all had highly efficient speaker systems and listened at low to moderate SPL levels than intergrated amps are fine,for those of us who listen at high SPL levels ,have inefficient 4 ohm speaker systems ,and listen to demanding material such as rock,heavy metal & orchestral ,the need for separate amplification becomes clear mathematics.

Yes, of course there are speakers that need more power than is readily available in an integrated, and if you have one of these speakers you have no choice but to use a separate amp. I get that of course. ..Ditto if you want to add channels in a multi-channel system.

But I disagree that there are engineering-based constraints on how powerful an integrated amplifier can be before it is audibly compromised. You mention noise floor, S/N ratios, cross-talk, etc.. I know of no reason why the separate sections of an integrated amplifier cannot be adequately isolated within the same chassis so as to perform just as well in these respects as separates. To wit: McIntosh's highest powered 300w/ Channel Integrated amplifier has the same or better THD, S/N, cross-talk, etc. specs of all the other integrates in their lineup. If what you said was true, as output power went up, these specs would deteriorate. Heck, ALL of their Integrated amps have specs that exceed our hearing threshold. ..Sure, they'll make sure their separates do a little better in most respects, but who cares if even their cheapest amp or integrated is better than our hearing.?

If they wanted to McIntosh could easily make a 1000w/Channel integrated amplifier with specs that outperform our hearing. ..Heck, there are plenty of commercial integrated PA amps that do this already but golden-ear audiophiles (not saying you necessarily) would dismiss these for 2-channel audio applications.

As an aside, I love the McIntosh brand, but it's kinda ridiculous how inefficient their speakers are. ..It's a bit convenient that the ONLY speaker with such low efficiency and high power demands is made by the ONLY company offering a 2000 watt amplifier. They may sound great but so too do a dozen other brands with less onerous power requirements

 

[Mike Gibson]

One possible reason the OP hasn't replied much to this thread just might be the content. For every post that's on topic there are several more wandering about the audio universe that have no actual bearing on the OP's original question. Personally I don't care that the thread meanders about the landscape as long as it stays friendly and somewhat informative. There are folks who want to help, those who would rather disrupt and those who feel everyone is entitled to read their opinions, and those who want to show you what they have. It's all good except for the disruptive souls who are a plague to the online forums they frequent. For the most part this group is self policing. I have to intrude very little here and that makes me happy and I'm sure it's a relief to the regulars here. So carry on and to the OP there is a lot of good information in here once you separate the wheat from the chaff.

 

[kevzep]

I was going to buy a C46 at the time I bought the C48 I have had for nearly 6 years now. The only thing that took me the route to the C48 was the fact I found one for a good price, and the USB input was a consideration too.
There weren't any C46's around at the time I wanted to buy.
I don't know if it sounds any different to the C48, but I found the C48 to be a "next level" experience compared to the C40 I had at the time, the spec's on paper don't look too different, but I have found spec's to play some part but don't tell the full story.

 

[62caddy]

The EQ control points chosen is my main complaint with the C46. I'm not overly concerned with specs where Mc is concerned and have yet to be disappointed with a Mc separate that's operating to spec.

As to S/N, the 90 dB and 80 dB specs of my C32 and MX113 are more than adequate for the vast majority of the material I listen to - most of which contains higher noise levels in the recordings than the playback equipment itself.

 

[Z4J]

Well over a year in the making, but I found a nice deal on a C46 and MC402. A dramatic difference over the 6300. The dynamics, clearity and strength is perfect for me. At this point I can say I've found my match. I love the 6300 and for the price point, it's excellent for a bookshelf type setup-imo. With that said, it does not hold a candle to the 46/402 combo. High quality like concert feel--to me at least. And I understand I only have Klipsh

 

[TSmith8605]

Nice! Congrats!