Marantz 8b

[BassmanBruce]

Hello to all, I am new to this forum.

I must confess, I do not own, or have any experience with Klipsch speakers, but will soon be "borrowing" a friends pair of La Scalla's.

Reason for writing is my experience with the fabulous Marantz 8b power amplifier.

At, now 60 years young, I have had and built may power amplifiers. As a paid musician, bassplayer, I have a good ear, and also enjoy

repairing/modding friends guitar amps (tube, of course).

About 5 years ago, I purchased a 7c, 8b, 10b combination from a customers wife after he passed away.

Each output tube in this amplifier (8b) has a coupling capacitor (4 total). The originals are made by Goodman. If you remove these four capacitors and replace them with four Panasonic EF series of the same value, the difference is astounding. The EF designation is not a Panasonic number, but is a prefex in the Digikey datalog, where they can be purchased.

I have had the privalidge to have many conversations with Frank Van Alstine. The subject of coupling capacitors came up one day, and I told him of my dismay in failing Jensen copper foil/paper/in oil capacitors. I asked him what he likes, and was told about the Panasonic caps. He told me he tested many different types/brands of capacitors, and found these Panasonic caps had the lowest "inductive reactance" of all tested. I then tried a set of these capacitors in both my Dynaco Mark 3's and Stereo 70. The Mark III's have the Posiedon boards in them. Well, this capacitor (very inexpensive also) sounds really excellent!

I have put this cap in the 8b.

Of all the amplifiers I have owned, both tube and solid state, the Marantz 8b sounds the best. The timming, speed, warmth, accuracy with this amplifier just wins in my book. Musician friends of mine come over and listen and say "I have never heard sound like that!" Goose bumps are the word of the moment.

Before I forget, take that pair of 6BH6's out of your 8b and put in a pair of E90F Mullard/Phillips tubes. ($18 each on ebay). They, along with the cap changeout, will really make your 8b sing!!!!!

Thorens TDD125 AB Mark II with Denon DL 160, set up with the Baerwald Arc Protractor

Marantz 7c preamp, stock w/ Telefunken smooth plate tubes

Marantz 8b modded as above

Speakers- Ralph Hellmer disigned, home made (by me) 3 way transmission line using Audax Aerogel 8" woofer, Audax Aerogel 4" midrange and Dynaudio Dome tweeters

Thanks for reading! I look very much forward to hearing the La Scallas on my system.

[Dennie]

Hey Bruce, Welcome to the Klipsch Forum, we're glad you're here! [<)] You see, we need a "Bass Player" for the Klipsch Marching Band!! LOL I'm joking!

I'm not into tube amps (yet) but a lot of people here are and will have many comments.

I just wanted to say Welcome and I hope to see you around.

Dennie

[Audible Nectar]

Very nice[]

The Marantz 8b is probably the only amplifier I do not own that I can say that I would like to own. Trouble of it is, when one has three rebuilt-to-the-hilt pairs of tube monoblocs it's hard to convince the wife and my wallet that I need another[8-|]

One pair are the NOSValves VRDs - a custom built for Heritage Klipsch amplifier solution that possess a stellar combination of fullness, warmth, flow, and authority in a tube rectified KT88 ultralinear design. A simple search here will convince you of the "hit" these amps have become around here.

Then I have two sets of McIntosh MC30s, which have been rebuilt with two differing parts packages. I went whole hog with about $800 worth of parts (75% of that was coupling caps - Sonicap Platinums) on the first pair - the end result (thanks to a fellow forum member) of a series of cap evaluation experiments. This was a real education as to what parts can do for the sonics of a build, especially when the finer points of the sonic finish are paid attention to. These are about as close sonically to triodes in push pull I've come across without actually being triode, as the caps completely get out of the way of the build leaving a wonderful sounding circuit remaining.

I also have a second set of MC30s with Russian PIO caps, which are intentionally "laid back", having that PIO kind of sound that I like in a vintage amp.

This being the culmination of my search for the ultimate amplifiers for my Heritage Klipsch.

With all that said, the Marantz might well be the amp I shouldn't have left behind. In a world of limited resources, I had to make choices. But I can absolutely tell you that if I were required by the audio powers that be to rescue another vintage amp, the 8b would top the list. One of a select few "all timers" absolutely worthy of restoration and play.

Thanks for sharing your results. That's absolutely valuable information - how to rebuild/what parts to use are always interesting conversation, and it helps the board at large consider choices that have worked for others.

[sheltie dave]

Bruce, where is the tube vendor located in the Midwest?

[BassmanBruce]

One thing I forgot to mention in my first post about the Marantz 8b is the speaker cable I use.

A close audiophile buddy of mine, Ralph Hellmer in Richmond, Va came down for a visit and

brought with him an 8 foot pair of "Luminous Audio Technology" "Synchestra Signature" speaker cables.

These cables are made out of cast, "single crystal", pure copper, made by ONO in Japan.

It was about half a song before I wrote him a check for these cables (he is a dealer for them). They are

expensive ($690 for the pair), but are worth every penny.

I have tried them on every amplifier I own, and in my book, they are a winner.

Thanks, Bruce

[Broseman]

Hi Bruce,

I found your post via Google. I was wondering what your complete set is. Source, pre, speakers, etc.

Thanks,

Ambrose

One thing I forgot to mention in my first post about the Marantz 8b is the speaker cable I use.

A close audiophile buddy of mine, Ralph Hellmer in Richmond, Va came down for a visit and

brought with him an 8 foot pair of "Luminous Audio Technology" "Synchestra Signature" speaker cables.

These cables are made out of cast, "single crystal", pure copper, made by ONO in Japan.

It was about half a song before I wrote him a check for these cables (he is a dealer for them). They are

expensive ($690 for the pair), but are worth every penny.

I have tried them on every amplifier I own, and in my book, they are a winner.

Thanks, Bruce

[BassmanBruce]

Hi ambrose,

Here is my "A" system,

Music Hall 25.2 cd player with Ralph Hellmer power cord and interconnect.

Thorens TD 125 AB Mk II with either Shure V15 type III or Denon DL160

Marantz 7c preamp, stock, with Telefunken smooth plate tubes (original)

Marantz 8b power amp, upgraded with E909f first stage tubes and Panasonic EF (digikey part number prefex) output tube coupling capacitors.

Luminous Audio Technology Synchestra Signature speaker cables

Speakers are home made (by me), designed by Ralph Hellmer. They are three way "transmission line" with 8 inch Audax Aerogel woofer, 4 inch Audax Aerogel midrange, and Dynaudio dome tweeters. These speakers are 94-95 db sensativity.

Thanks for your interest, Bruce

[soundbound]

Bruce,

I replied to your questions to your Klipsch PM.

[mustang guy]

Hi ambrose,

Here is my "A" system,

Music Hall 25.2 cd player with Ralph Hellmer power cord and interconnect.

Thorens TD 125 AB Mk II with either Shure V15 type III or Denon DL160

Marantz 7c preamp, stock, with Telefunken smooth plate tubes (original)

Marantz 8b power amp, upgraded with E909f first stage tubes and Panasonic EF (digikey part number prefex) output tube coupling capacitors.

Luminous Audio Technology Synchestra Signature speaker cables

Speakers are home made (by me), designed by Ralph Hellmer. They are three way "transmission line" with 8 inch Audax Aerogel woofer, 4 inch Audax Aerogel midrange, and Dynaudio dome tweeters. These speakers are 94-95 db sensativity.

Thanks for your interest, Bruce

I noticed you built your own mains. I would love to see pictures and know if those plans are in the public domain. Also, have you tried any of the Klipsch Heritage speakers as your mains? If so, how do they compare, other than raw efficiency, with the Hellmer designs?

Thanks

[BassmanBruce]

Good morning to you.

Looks like you have quite a sound system.

My speakers I call the "Looking Glass" speakers when I talk to my friend Ralph, the designer.

They are very fast and image to beat the band. They have a hugh midrange portrayal. I did go to

a friends and heard his LaScala's last week. He has a store and they were in a large area.

I liked them very much. Especially in the upper bass, lower midrange synergy.

My speakers are 7 feet apart, and I sit 9 feet in front of them. LaScala's would be too big for

my listening area I believe. I am considering a pair of Chorus II's that will come available at

the end of the month to give them a try. If I don't want them I have a contact that does.

After hearing the LaScala's, I have started playing with the packing in the line of my TL's. They

are now in the middle of a long wall, and need a little help in the low bass. I have found another

octive since my tuning started, and now have that upper bass, lower midrange area improved.

If you send me your email address I will send you some pics of the Looking Glass speakers.

Thanks, Bruce n4jhy@yahoo.com

[sunnysal]

No doubt the 8b was and is one of the great amps EVER. Both it and the 7C are highly regarded, there are some tweaks that even the designer thought could improve them, I will try to find the relevant articles and post them. The 8b was arguably Sid Smith's best design (though many pine for the 9). I still want one and hope to acquire on some day, alas I dont know where in my house I would use it but...

regards, Tony

[BassmanBruce]

Thanks Tony. I know an audio component designer that knew Sid Smith (lucky guy), and we have discussed the subject fairly recently.

You know, I have tried several of the mods to the 8b, and to be honest with you, I keep going back to the stock design. The "timing" on this amplifier is just perfection (to me) and any of the mods I have tried change this charactoristics dramatically. My Audax Aerogel speakers are so fast (only thing faster might be an electrostatic) and amplifier pace or timing being right is essential. It's not an 8B any more with the mods (even ones suggested by Sid himself).

Now I will say I did replace the four coupling capacitors that feed the output tubes with the same value. Sid had reccomended going from a 0.1 to a 0.22 mfd, but I did not like that, so back to the 0.1's.

Frank Van Alstine, a truely revolutionary audio designer of today, reccomended a Panasonic coupling capacitor to me after I complained about Angela/Jensen foil and paper in oil capacitors were failing on me (my favorites at the time) in my Dynaco power amps. He spoke of very low "inductive reactance" on these capacitors. They are cheap, and they are fast, warm, and sound so un-colored. Can't say that about all those expensive polyprop's that one can waste ones money on.They start with and EF in the digikey catalog. That's a digikey prefex,not a Panasonic prefex.

Those capacitors, plus the use of the Mullard E90F tube (two) in the first stage of the 8b, and man, it's the BOMB!!

I can "steer" the sound of the 8B with different output tubes. I have a pretty big collection of EL34's.

I really want to bring my friends LaScala's over to run on my equip. He is running them on a Sansui receiver and turntable.

Please save up, sell some stuff, and treat yourself to an 8B! Bruce

[sunnysal]

I agree Bruce, why mess with a great thing. I agree with staying away from the signal path but perhaps consider on the 8b and 7C that they could use some help in the PS to give it a little more "umph" ? T

[BassmanBruce]

I am running my 8b in triode mode, and it is rated at 20 wpc. My speakers are 94 db sensitivity, and I never felt I needed more umph. I don't listen real loud.

B.

[BassmanBruce]

STOP THE PRESSES!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Being a "capacitor roller" I have a large drawer full of many brands/types of interstage coupling capacitors for my dynaco's and Marantz 8b.

My favorites used to be the Jensen copper/paper in oil, but after a bunch of them failed I found the Panasonic EF series, and really liked them.

I have tried many polyprops, both metalized and foil and just don't like them. I find them dark, and slow. Good in some areas, and bad in others.

With all I have been reading about the somewhat new crop of capacitors, especially the Russian millitary teflons and foil in oil, I decided to take a chance

on some Russian K40y's in 0.1 @630 volts. Not being a rich man, the pricing of some of the capacitors I might like to hear is out of the question- $135 per

cap is not realistic for me.

The K40Y caps, foil/paper in oil cost me $2.70 each and $4.00 shipping from a guy here in the US and were bought on Ebay. I received them two days ago, and ran them with 450 volts DC for 24 hours. I paralled the the four of them for this initial break in.

I installed them this morning in my Marantz 8b, and want to tell you- THESE ARE SOME FABULOUS CAPACITORS !!!!!! I have read that many people like these foil/paper in oil capacitors better than the Russian teflons.

These capacitors are the best sounding capacitors I personally have ever heard in my many tube amplifiers!!!

IMAGING- 10+

MIDRANGE SIZE 10+ THE BIGGEST I HAVE EVER HEARD IN MY SYSTEM !

MIDRANGE SMOOTHNESS 10+

BASS SPEED- VERY FAST- MY 8 " AUDAX AEROGEL'S IN A TRANSMISSION LINE TAKE ADVANTAGE OF THIS SPEED IN THE BASS AND THE BASS IS ALSO INCLUDED IN THE IMAGING!!!

LOW LEVEL RESOLUTION- 10+ EXCELLENT !!!!

HIGH FREQUENDY AREA- 10+ CYMBALS ARE SO VIVID AND CLEAN! BEST I HAVE HEARD IN MY SYSTEM

UPPER BASS/LOW MIDRANGE- 10+ ITS HUGH, FAST, WARM AND CLEAN. CELLOS= GOOSEBUMPS ( MY FAV INSTRUMENT )

All you guys running those wonderful Klipsch heritage speakers with tube amplifiers, I can't tell you enough to give these K40Y's a try in your amplifiers.

These are the most musical capacitors I have heard. PERIOID!

I guess you can tell I am excited. I have several audiophile friends that call me "THE EAR". These capacitors deliver "!!

These capacitors A R E T H E B O M B !!!!!

Merry Christmas, Happy Honukka, Happy Holidays to all you audiophiles, and yours.

Bruce in South Carolina Christmas has come early here !!!!!!

[mike stehr]

You sold me years ago...

The K40Y capacitors are excellent caps for the price. I've used them for quite some time in single-ended amplifiers and push-pull amps. Some claim the Sprague Vitamin Q caps are a little better, but they are more scarce and cost more.

The green cased K75 are good caps as well.