AudioCircle

Audio/Video Gear and Systems => Tube-o-phile Circle => Topic started by: glynnw on 11 Feb 2019, 10:20 pm

Title: How can a 40 year old amp sound this good?
Post by: glynnw on 11 Feb 2019, 10:20 pm
Like may Circle members I have been on a lifelong search for the perfect amp (at least to my tastes) and have owned at least 6 or 7 amps in the last 5 years - including Shindo, First Watt, Music Reference, Carver, a custom 2A3, a custom F2, and more...you get the picture.  A while back I purchased a pristine Conrad Johnson MV75a - bought it from the original owner who had had it maintained by a tube place in Seattle.  Having purchased a new CJMV45a-1 back in the day, I bought it more as a collector piece than with an intention to use it heavily.  I love this amp, played through both a Spatial Audio M3TM and Daedalus Custom Studio spkrs.  It brings an ease to the music, a flow if you will, that I seldom find in amps.  No claim that this is the last amp for me (although at age 72 it might well be) but I have to ask what the heck have amp designers learned in the 40 years since this MV75 was designed? 
Title: Re: How can a 40 year old amp sound this good?
Post by: FullRangeMan on 11 Feb 2019, 10:42 pm
Imo the transformers are great in this amp, a long with the huge power 75W, by the little I know other parts are usual.
Congratulations
Title: Re: How can a 40 year old amp sound this good?
Post by: FullRangeMan on 11 Feb 2019, 11:24 pm
About the title of this topic I wish clarify that a current new tube amp have real chance to sound worse than a vintage tube amp from the same price, due some factors as current tubes have short life and worse SQ than the NOS tubes, mainly NOS military tubes.

A simple SE tube amp from 1930 years as AD1 or 300B already have great SQ for current standards and in the next centuries also will have great SQ compare to the amps of the future, the tube amp sound becomes a classic, a reference.
Title: Re: How can a 40 year old amp sound this good?
Post by: OzarkTom on 11 Feb 2019, 11:45 pm
Marantz 8B is another to look at. Made in 1962 and now selling for 3K and more on Ebay. That one is better sounding than the CJ, but at the current price probably out of reach for many.

At one time I could buy them for $600-800. Now where is that Delorean.
Title: Re: How can a 40 year old amp sound this good?
Post by: Early B. on 12 Feb 2019, 12:23 am
My guess -- at the end of the day, it all comes down to build quality. This applies to most industries, not just audio. Decades ago, goods were generally made with higher quality parts and designed to last. My first car was made of US steel. Today, it's fiberglass which will dent if you press your finger on it too hard. Technology notwithstanding, which car would you choose today?

The design of amps hasn't fundamentally changed in 50 years, so what's left? Parts quality. Today, a high quality amp will cost several thousand dollars and is out of reach for most people.   
Title: Re: How can a 40 year old amp sound this good?
Post by: FullRangeMan on 12 Feb 2019, 12:35 am
My guess -- at the end of the day, it all comes down to build quality. This applies to most industries, not just audio. Decades ago, goods were generally made with higher quality parts and designed to last. My first car was made of US steel. Today, it's fiberglass which will dent if you press your finger on it too hard. Technology notwithstanding, which car would you choose today?

The design of amps hasn't fundamentally changed in 50 years, so what's left? Parts quality. Today, a high quality amp will cost several thousand dollars and is out of reach for most people.   
Correct. Recently I said in other topic to chosse a amp by built quality not by sound quality and was criticized.
Title: Re: How can a 40 year old amp sound this good?
Post by: glynnw on 12 Feb 2019, 01:07 am
FYI, I am using new KT120 tubes - I think the others are NOS, but the markings are almost gone.
Title: Re: How can a 40 year old amp sound this good?
Post by: FullRangeMan on 12 Feb 2019, 01:16 am
FYI, I am using new KT120 tubes - I think the others are NOS, but the markings are almost gone.
Nice, when you had a consistent info on the time life of these 120 let me know please.
Title: Re: How can a 40 year old amp sound this good?
Post by: galyons on 12 Feb 2019, 02:21 am
Correct. Recently I said in other topic to chosse a amp by built quality not by sound quality and was criticized.

Because the statement lacks merit.  Sound quality is paramount.  Build quality is a waste of effort and resources if it does not sound good. (There are way too many examples of that foolishness.)  It follows that a good design, well implemented is most likely to produce quality sound. But to say "chosse (sic) a amp by built quality not by sound quality" is the opposite of good sense if one want to reproduce music with fidelity and quality.

Why is that concept so difficult to comprehend?

Cheers,
Geary
Title: Re: How can a 40 year old amp sound this good?
Post by: Early B. on 12 Feb 2019, 03:33 am
Because the statement lacks merit.  Sound quality is paramount.  Build quality is a waste of effort and resources if it does not sound good. (There are way too many examples of that foolishness.)  It follows that a good design, well implemented is most likely to produce quality sound. But to say "chosse (sic) a amp by built quality not by sound quality" is the opposite of good sense if one want to reproduce music with fidelity and quality.

I believe what FRM is saying is that great amp designers are more likely to use high quality parts because they know that quality improves the sound. Very few of us have the luxury of testing an amp in our systems before we buy it, so one approach is to buy based on build quality. That's how I bought my amps.
Title: Re: How can a 40 year old amp sound this good?
Post by: galyons on 12 Feb 2019, 03:44 am
IMO, the problem with "modern" tube amps is that designers have, for years now, made them sound more like solid state amps than traditional tube amps. Audio Research led the decline into overly sophisticated circuits, other manufacturers followed.  Sand regulated  filament supplies, sand rectified and regulated B+,  transistor based constant current sources, etc. have robbed modern tube amps of the very characteristics that make a tube amp a tube amp. As speakers become more " sophisticated", (read as less efficient), designers pushed the power tube dissipation to near the limit in search of ammo in the wattage wars.  Now, not only do the modern tube amps not sound as good, they are often less reliable, as well.

I am still a SE DHT, paper-in-oil capacitor, horn speaker luddite!  So take my opinions with that in mind.

Cheers,
Geary



Title: Re: How can a 40 year old amp sound this good?
Post by: galyons on 12 Feb 2019, 04:07 am
so one approach is to buy based on build quality. That's how I bought my amps.

How does one go about doing so?  Purchase based on schematic? Purchased based  on BOM? ... Audio mag reveiws? ....Pictures? 

Asking for a friend!  :D

Cheers,
Geary
Title: Re: How can a 40 year old amp sound this good?
Post by: witchdoctor on 12 Feb 2019, 04:27 am
My guess -- at the end of the day, it all comes down to build quality. This applies to most industries, not just audio. Decades ago, goods were generally made with higher quality parts and designed to last. My first car was made of US steel. Today, it's fiberglass which will dent if you press your finger on it too hard. Technology notwithstanding, which car would you choose today?

The design of amps hasn't fundamentally changed in 50 years, so what's left? Parts quality. Today, a high quality amp will cost several thousand dollars and is out of reach for most people.   

I happen to agree with build quality but amp design HAS fundamentally changed but not because of the amps per se, but because of room correction systems. The OP stated he was never 100% satisfied with his previous amps. I get it but was the amp the problem or how the amp sounded in his room?

paradigm has ARC room correction in their Anthem and Paradigm line of amps. It is a HUGE difference. Check out my review here:

https://www.audiocircle.com/index.php?topic=162334.new#new
Title: Re: How can a 40 year old amp sound this good?
Post by: Tyson on 12 Feb 2019, 04:29 am
IMO, the problem with "modern" tube amps is that designers have, for years now, made them sound more like solid state amps than traditional tube amps. Audio Research led the decline into overly sophisticated circuits, other manufacturers followed.  Sand regulated  filament supplies, sand rectified and regulated B+,  transistor based constant current sources, etc. have robbed modern tube amps of the very characteristics that make a tube amp a tube amp. As speakers become more " sophisticated", (read as less efficient), designers pushed the power tube dissipation to near the limit in search of ammo in the wattage wars.  Now, not only do the modern tube amps not sound as good, they are often less reliable, as well.

I am still a SE DHT, paper-in-oil capacitor, horn speaker luddite!  So take my opinions with that in mind.

Cheers,
Geary

Agreed.  I've churned through a fair number of tube amps and have a few "rules of thumb" when it comes to buying anything nowadays:

1. Must use octals in the driver stage.  Sorry but octals just sound better than peanut sized 9 pin tubes.
2. Must use a tube rectifier.
3. Single Ended generally sounds better than push-pull.  Single ended parallel is the way to go if you need more power.
4. Small amounts of feedback can be OK, but moderate or large amounts of feedback always sounds bad (tube or SS)
5. Parts quality is important, especially transformers. 
Title: Re: How can a 40 year old amp sound this good?
Post by: witchdoctor on 12 Feb 2019, 04:33 am
Agreed.  I've churned through a fair number of tube amps and have a few "rules of thumb" when it comes to buying anything nowadays:

1. Must use octals in the driver stage.  Sorry but octals just sound better than peanut sized 9 pin tubes.
2. Must use a tube rectifier.
3. Single Ended generally sounds better than push-pull.  Single ended parallel is the way to go if you need more power.
4. Small amounts of feedback can be OK, but moderate or large amounts of feedback always sounds bad (tube or SS)
5. Parts quality is important, especially transformers.

How much of that tube magic can be obtained with the iTube in your opinion used as a buffer between a source and a preamp?
Title: Re: How can a 40 year old amp sound this good?
Post by: Tyson on 12 Feb 2019, 04:46 am
How much of that tube magic can be obtained with the iTube in your opinion used as a buffer between a source and a preamp?

If you're running an SS system and just want some better tonality, a buffer like the iTube2 is a good option.  On the other hand, if you're running a fully tubed system already (I am nowadays), then an iTube2 is redundant. 

The tube the iTube2 uses, the 2C51, is one of the very few 9 pin tubes that sounds (and measures) like a 6SN7.  Which is probably why I like that buffer so much (and it's also used in the iDSD Pro, which I really love). 

For pure tube magic, nothing really beats my Type 45 SET amp with 6SN7 drivers.  It's just really low powered at only 2 watts.  Luckily I have 97db efficient speakers so it's possible to use an amp like that.  Beauty uber-alles is really the style of that amp.

However, the 45 mostly sits in the closet because the Dennis Had Inspire amps have a similar level of beauty and clarity but with quite a bit more grunt.  Love those things. 

EDIT:  But, to go back to the original post, re: how can something so old sound so good.  I have another crazy theory.  That electronics (like good quality tube gear) actually sounds better with age.  And the more age, the better.  Obviously some parts wear out and need to be replaced (electrolytic caps, especially), but I think other parts like transformers, wires, film caps, etc... all mellow and bloom over the years. 

Which is part of why I never buy tube gear new.  I'm perfectly happy to let someone else put a few thousand hours on a piece of gear.  The more, the better. 
Title: Re: How can a 40 year old amp sound this good?
Post by: Early B. on 12 Feb 2019, 05:00 am
How does one go about doing so?  Purchase based on schematic? Purchased based  on BOM? ... Audio mag reveiws? ....Pictures? 

After buying lots of amps (tube and SS) over 25 years, you learn what to look for.   
Title: Re: How can a 40 year old amp sound this good?
Post by: FullRangeMan on 12 Feb 2019, 05:33 am
Because the statement lacks merit.  Sound quality is paramount.  Build quality is a waste of effort and resources if it does not sound good. (There are way too many examples of that foolishness.)  It follows that a good design, well implemented is most likely to produce quality sound. But to say "chosse (sic) a amp by built quality not by sound quality" is the opposite of good sense if one want to reproduce music with fidelity and quality.

Why is that concept so difficult to comprehend?

Cheers,
Geary
Hey Geary Iam in audio since 1974 and already see this salesman talk many times, I call it golden the pill, always to sell again to naive audio buyers, since listen in a shop is difficult to perceive any sound improvement and as they are young people they lack audio listening experience, which are different from live music.

Your statement is the summary of the modern audio dealer trickery and planed obsolescence to sell poor made amps with cheap parts that lasts 5 years for a high price due to their supposed sound quality, while with high quality parts and a simple SE design the equipment would last 20 years or more or as in this topic case 40 years.

Sound quality with good parts will be even better than the cheap parts usual 10% precision resistences and raw EI 0.5mm silicon steel. Saying that a good design with cheap parts can sound good is to induce the music lover to spend your hard earned money in a poor made amp to buy again after a couple of years preferable in your shop.

Good design is a variable opinion concept according everyone, by example the ''good'' design of Macintosh is a disaster of excess redundant parts that even increases internal heat and modify the sound of the tube to create the ''Mac sound'', the owner tube rolling and the sound is always the same!

The good sound and reliable design of tube amps were made in the 1930s and 40s and were most simple SE amps with small count parts. When I see a tube amp underside photo I can say if it will sound good and have a short life.
Have a nice day.
Title: Re: How can a 40 year old amp sound this good?
Post by: galyons on 12 Feb 2019, 05:34 am
After buying lots of amps (tube and SS) over 25 years, you learn what to look for.

Ok, I guess it must be WAG!!!  To me, it's all about the music, (sound) reproduction.  I have never figured out how to "look for" that.  I have been buying amps for over 50 years and building tube equipment for half that(other than Dynakit ST40 and PAS 3X in the '60's).  Sadly I only know what to look for after I know what I hear.  Otherwise....

Cheers,
Geary
Title: Re: How can a 40 year old amp sound this good?
Post by: FullRangeMan on 12 Feb 2019, 05:41 am
3. Single Ended generally sounds better than push-pull.  Single ended parallel is the way to go if you need more power.
4. Small amounts of feedback can be OK, but moderate or large amounts of feedback always sounds bad (tube or SS)
I highlight the SE topology, with PP or NFB the soundstage are not deep and palpable as SE and zero feedback, mainly if one use monopole speaker that emit sound only to front, usually this mean small power, unless it use a hot big triode.
Title: Re: How can a 40 year old amp sound this good?
Post by: galyons on 12 Feb 2019, 05:57 am
...
Your statement is the summary of the modern audio dealer trickery and planed obsolescence to sell poor made amps with cheap parts that lasts 5 years for a high price due to their supposed sound quality, while with high quality parts and a simple SE design the equipment would last 20 years or more or as in this topic case 40 years.

...

Ok FRM.  If you got that from what I posted,  I have no idea how to respond.  We are in totally different comprehension universes.

I have built/rebuilt every piece of equipment in my kit from 1960's EV Sentry IVA horns, (rebuilt with custom x-overs), , power amps, preamps, phono stage, tape head, SUT and tubed multibit DAC.  My power amps are all SE DHT, (45, 2A3, 300B, SV801-10), that I built, (except for vintage Scott, Heathkit , Fisher and HK, which I restored).  So I would obviously speak in "modern audio dealer trickery and planed (sic) obsolescence" :duh:  I can imagine my modern audio dealer sales pitch now, "Pssst, do not buy any of this stuff, DIY all the way!"

I do own some modern tube equipment, Rogue 150M Magnums, Rogue 99 preamp, and a bunch of Golden Tube Audio SE40's. Only the SE40's see any service time. (I run the Golden tube Audio Yahoo group.)  So I can see we are not on the same page! H@!!, we are not even looking at the same book!

Cheers,
Geary



Title: Re: How can a 40 year old amp sound this good?
Post by: BobRex on 12 Feb 2019, 02:45 pm
I have an MV75a1 boxed up in my basement.  Connected to a PV5, it was my main system for over 10 years.  Then I discovered SET and ran a 2A3 amp (Wellborne Moondogs) for another 10 years or so.  The MV75 was/is a great amp, esp. for the early '80s.  Think about replacing the input connector and possible the power switch.  I went through 2 of the push button switches before I replaced them with a paddle switch.  Also, check to see if you have an "a" or an "a1".  The "a1" mod removed some of the grain and opened up the top end a little bit.
Title: Re: How can a 40 year old amp sound this good?
Post by: Carl V on 12 Feb 2019, 03:17 pm
LOL
My first good system
Was PV5, MV-50 & Vand. 2Ce then a second MV50.
Then 2w Subs then the MV52 Upgrades.

That PV5 is a nice warm pre-amp with a great PHONO
the MV series Amps were always Pleasant & Tubey...in a good way.
Their Premiere line always had better parts & sounded better, for more money.

cj amps have always been 'musical' not trying to be SS amps in disguise imho

Many of those older designs have a nice sound quality.
Title: Re: How can a 40 year old amp sound this good?
Post by: mcgsxr on 12 Feb 2019, 03:35 pm
I really enjoyed the Magnavox console pull (sep el84) I used for 10 years.  Must have been from the 60’s. 

I am currently loving a Sugden Optima 140 integrated from around 1995. 

I have tried many kinds of amps over the years and always find that matching speakers and amps is a fun and rewarding pursuit. 

Nice CJ!
Title: Re: How can a 40 year old amp sound this good?
Post by: mick wolfe on 12 Feb 2019, 03:37 pm
Sounds a lot like one of my early systems. PV5/MV50/JSE Model 1's. I believe if I could hop in a time machine, I would find it superb even by today's standards. A few years later I put together a CJ system featuring a PV8/MV75/Spendor 2/3 combo. Very good, but didn't match that first CJ system.
Title: Re: How can a 40 year old amp sound this good?
Post by: FullRangeMan on 12 Feb 2019, 04:04 pm
Geary, this is a cheap OPT usually found on guitar and hi-fi amps:
(https://www.audiocircle.com/image.php?id=76188)
Title: Re: How can a 40 year old amp sound this good?
Post by: Mark Korda on 12 Feb 2019, 04:31 pm
Hi,
    there was a guy before the internet came around called Walt Bender. He ran Audiomart which was the primo classified monthly where the search for vintage became a little easier. He said something radical that might help here. It was in Listener Sept./Oct. 2001 in a Peter Breuninger article on the Dyna Stereo 70.
    Transformers take 3 to 6 months to come to 80 percent performance but take over 40 years to gain the remaining 20 percent. This explains the stratospheric pricing of old Western Electric gear. It's not because it's collectible, it's for the sound.
  True or not, It always makes me wonder. I hope this helps....Mark Korda
Title: Re: How can a 40 year old amp sound this good?
Post by: Freo-1 on 12 Feb 2019, 05:15 pm
To the OP:  Welcome to tube audio. 


The are several reasons why the CJ tube amps sounds enjoyable.  The major reasons have to do with the differences in transfer function between tube amps and solid state amps.  Two significant items are the tube amp's output transformer, and the "soft clipping" characteristics of tubes vs. solid state.  As far as tube topology is concerned, SE, P/P, ultralinear, pentode, etc. all can sound good, as long as good engineering principals are followed, and the amp is mated to a set of speakers that work well with the amp (which is the real trick to getting good sound). 


I have two sets of DIY tube amps, both which sound excellent.  I'm not a big fan of current production tubes, so instead  went down the DIY amps road and used good old NOS tubes.  The driver tubes for both sets of amps are 6BL7's, which is a very stout tube, well made, and long lasting (they were made for TV sets, which had to be reliable).  One set of mono blocks uses a quad of 1625 tubes for the output (which is a 12 volt version of the good old 807 tube made famous in WW2).  The amps supply about 110 watts of clean tube goodness.  The other mono block amps use a pair of 6883B (which is a 12 volt version of the 6146B).  These output around 80 watts of very good sounding power.  The tube compliment is reasonably priced, and still obtainable. 


Both amps have a Thomas Mayer clone of a 6AH4 preamp that drive the power amps.  The 6AH4 preamp is very quiet, and uses transformer coupling to the power amp.  The nice thing about DIY is that one can make them with point to point wiring, use better quality parts, and get a great sounding product.  Both sets of amps use Mundorf Silver/Gold coupling caps, and those make a huge difference in sound improvement. 


Enjoy the CJ amp.  Tube audio can be very seductive.  Enjoy the ride. 
Title: Re: How can a 40 year old amp sound this good?
Post by: witchdoctor on 12 Feb 2019, 06:32 pm
Hi,
    there was a guy before the internet came around called Walt Bender. He ran Audiomart which was the primo classified monthly where the search for vintage became a little easier. He said something radical that might help here. It was in Listener Sept./Oct. 2001 in a Peter Breuninger article on the Dyna Stereo 70.
    Transformers take 3 to 6 months to come to 80 percent performance but take over 40 years to gain the remaining 20 percent. This explains the stratospheric pricing of old Western Electric gear. It's not because it's collectible, it's for the sound.
  True or not, It always makes me wonder. I hope this helps....Mark Korda

I saw an old Mcintosh amp on Craigslist which I thought would be just a repair job in waiting. Now I may go take a look as I think it is from the seventies so the 40 years has been clocked. :)
Title: Re: How can a 40 year old amp sound this good?
Post by: Freo-1 on 12 Feb 2019, 06:35 pm
There is a huge interest in the HK Citation 2 amps.  The output transformers are highly sought after.
Title: Re: How can a 40 year old amp sound this good?
Post by: ketcham on 12 Feb 2019, 06:37 pm
This is an interesting thread.  I love my amps now and look forward to many years of enjoyment!!!!!
Title: Re: How can a 40 year old amp sound this good?
Post by: Goosepond on 12 Feb 2019, 06:38 pm
The older I get, the better I used to be!!!  :green:

Gene
Title: Re: How can a 40 year old amp sound this good?
Post by: timind on 12 Feb 2019, 07:32 pm
A few months ago I bought a Fisher KX 90 (1965) integrated amp. After recapping the power supply, I'm enjoying it quite a bit. I think about swapping in newer coupling caps, but don't want to change the sound of the amp; too sweet as is.
Title: Re: How can a 40 year old amp sound this good?
Post by: Early B. on 12 Feb 2019, 08:05 pm
The older I get, the better I used to be!!!  :green:

Hilarious 'cause it's true!!

Title: Re: How can a 40 year old amp sound this good?
Post by: S Clark on 12 Feb 2019, 08:41 pm
About 15 years ago, Gary Dodd sat in my living room to hook up his prototype battery preamp.  At the time I had an old Knight Kit KB85, and he was duly impressed that it didn't have the weak bass he was expecting.  8-10 years later, he used the transformers of that amp to build a custom amp for me that he though was one of the sweetest sounding amps he' ever put together.  Old trannies can sound excellent.   :dunno:
Title: Re: How can a 40 year old amp sound this good?
Post by: Freo-1 on 12 Feb 2019, 08:44 pm
A few months ago I bought a Fisher KX 90 (1965) integrated amp. After recapping the power supply, I'm enjoying it quite a bit. I think about swapping in newer coupling caps, but don't want to change the sound of the amp; too sweet as is.


I would not be hesitant to update the coupling caps, as well as power supply parts.  I had a Fisher KX-200 some years back, and the refurbishment of coupling caps and power supply diodes made a marked improvement in the sound of the unit.  Still had that lush midrange, but it was like a veil had been lifted, and the music came across clearer.  Sold it to a good friend who uses it daily. 




Found more or less the same results back when I first got into tube gear with refurbishment kits from Vacuum Tube Valley for a pair of Dyna MK IV's and PAS-3.
Title: Re: How can a 40 year old amp sound this good?
Post by: FullRangeMan on 12 Feb 2019, 11:01 pm
About 15 years ago, Gary Dodd sat in my living room to hook up his prototype battery preamp.  At the time I had an old Knight Kit KB85, and he was duly impressed that it didn't have the weak bass he was expecting.  8-10 years later, he used the transformers of that amp to build a custom amp for me that he though was one of the sweetest sounding amps he' ever put together.  Old trannies can sound excellent.   :dunno:
Do it can be the isolation varnish is depleted?
Title: Re: How can a 40 year old amp sound this good?
Post by: OzarkTom on 13 Feb 2019, 12:52 am
One of the very best preamps I ever heard was the tube McIntosh C-22. It was from the 60's also. These are now selling on Ebay for anywhere form 3-7K. Mac reintroduced that in 2015.
Title: Re: How can a 40 year old amp sound this good?
Post by: timind on 13 Feb 2019, 02:18 am

I would not be hesitant to update the coupling caps, as well as power supply parts.  I had a Fisher KX-200 some years back, and the refurbishment of coupling caps and power supply diodes made a marked improvement in the sound of the unit.  Still had that lush midrange, but it was like a veil had been lifted, and the music came across clearer.  Sold it to a good friend who uses it daily. 




Found more or less the same results back when I first got into tube gear with refurbishment kits from Vacuum Tube Valley for a pair of Dyna MK IV's and PAS-3.

I plan on upgrading the rectifier diodes. Thought about the coupling caps, but the West German "Erofol" caps look cool. I like the flavor of the amp and don't really want to change it. If I want more clarity, I use another amp.

I've changed parts before to get "more" and only ruined the beauty of the original sound.
Title: Re: How can a 40 year old amp sound this good?
Post by: rollo on 13 Feb 2019, 08:45 pm
 Good is as good does. Not much new circuitry these days. CJ is a world class company. They have a house sound which to most ears works very well.

charles
Title: Re: How can a 40 year old amp sound this good?
Post by: Freo-1 on 13 Feb 2019, 09:58 pm
I plan on upgrading the rectifier diodes. Thought about the coupling caps, but the West German "Erofol" caps look cool. I like the flavor of the amp and don't really want to change it. If I want more clarity, I use another amp.

I've changed parts before to get "more" and only ruined the beauty of the original sound.


Understand completely.   :thumb:   



Title: Re: How can a 40 year old amp sound this good?
Post by: SET Man on 14 Feb 2019, 12:44 am
Like may Circle members I have been on a lifelong search for the perfect amp (at least to my tastes) and have owned at least 6 or 7 amps in the last 5 years - including Shindo, First Watt, Music Reference, Carver, a custom 2A3, a custom F2, and more...you get the picture.  A while back I purchased a pristine Conrad Johnson MV75a - bought it from the original owner who had had it maintained by a tube place in Seattle.  Having purchased a new CJMV45a-1 back in the day, I bought it more as a collector piece than with an intention to use it heavily.  I love this amp, played through both a Spatial Audio M3TM and Daedalus Custom Studio spkrs.  It brings an ease to the music, a flow if you will, that I seldom find in amps.  No claim that this is the last amp for me (although at age 72 it might well be) but I have to ask what the heck have amp designers learned in the 40 years since this MV75 was designed?

Hey!

     Well, maybe because of after 40 years of breaking in now is sound good?  :lol:

     I'm not an amp designer or electrical engineer but I'm a DIYer and I've built and tinker with audio for sometime now. I think tube amp technology haven't change much the past 40 years, what changed are parts. I have two SET amps, one pair that I've been using since 1999. SET design have been around since the dawn of audio. Sound great to me!

     What I have noticed is that older tube amps can sound mellow and this can make it sound what you could call "sweet" and this works well with many recordings that are bright sounding.

...

I've changed parts before to get "more" and only ruined the beauty of the original sound.

   I know what you mean, lesson learned the hard way. And that's why I stop doing that.

Buddy

 
Title: Re: How can a 40 year old amp sound this good?
Post by: FullRangeMan on 14 Feb 2019, 11:15 am
I know what you mean, lesson learned the hard way. And that's why I stop doing that.

Buddy
This is a sane approach to audio, I also dont change parts or tubes in good shape, just when they fail.