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I am considering buying a Marantz 8B. However, I have a choice between two different units with significant differences.
The first is electronically original (except for replacement of the selenium rectifier and two bypass capacitors) and includes tube adapters to allow use of 6AU6s in place of the 6BH6s for a somewhat more open soundstage (at least that's how it sounds to me).
The other 8B has been modified electronically by Bob Hovland so that the 6BH6s are replaced by 6HK5s or 6HA6s (triodes vs pentodes). I have not been able to find anything about this modification. I also have not auditioned this one yet to ascertain the difference. I do know that Bob Hovland is a respected audio engineer.
My primary question is whether the Hovland modifications decrease the resale value of the 8B.
The unit that is stock and comes with the adapters to allow use of 6AU6s has no physical modifications so using the adapters would never hurt the resale value.
Unfortunately, I can only afford one of them.
Any experience with units with the Hovland mods and thoughts on their effect on resale value?
Scott
Follow Ups:
Many years ago I had a pair of 8Bs modified by Bob. They were wired for mono and triode operation. The input tubes were 6HK5 and had 5687 for the phase splitter. I'm sure he replaced the selenium rectifier but as far as I know the power supply was otherwise stock. Of course the coupling caps were Hovlands. So basically his circuit using the 8B chassis and transformers.They sounded great.
In a fit of temporary insanity I sold them but no doubt most of us have similar stories. I have no definitive information on resale value but as in most things stock generally brings more $$.
In person Bob is the most gracious, unassuming, down to earth person you will ever meet.
Thanks for the input. The guy selling the 8B has both the stock version and the Hovland-modified version and I will be able to listen to both for comparison. I'm just wondering if the Hovland-modified version will sound that much better than the stock version to justify the decrease in resale value. I want to use whichever version I buy on a regular basis, so I want it sound good. However, I don't want to buy something that will be hard to resell someday or get a greatly reduced price.
Scott
If resale value is your prime criterion then stock is the way to go.
As has been posted, the 8B is a very fine amp and an all time classic. If it is indeed stock, then it could very well require some service in the future.
Regarding sound, I would expect the modified amp with the Hovland capacitors would sound different. Which one is better is for you to decide.
One other note on the subject of modifications, Sid Smith of Marantz, who had a hand in the design of the 8B, used to modify Marantz Model 7 preamps with whatever changes he felt were for the better. He also wrote up changes he felt were beneficial to the 8B. Somewhere I have some literature from him describing the mods.
I would be curious to see what mods Sid Smith had for the 8B. The stock one I'm looking at has had the selenium rectifier replaced with a silicon one, protection diodes installed for meter protection and the cathode bypass caps on the output tubes replaced. Other than that, it's stock and dead quiet. I do worry about having the original caps in the bias circuit because, if they go, they can take out some critical parts. I also wonder if the unit might sound better with more capacitance in the filtering section, although it sounds great now. Back in the day, large capacitors were large and expensive plus the old type silicon rectifiers couldn't handle the large current surges that larger caps would generate when charging. If I changed the filter caps, I'd leave the original can on the chassis so whatever I did could be easily reversed.
Scott
There are "Sid Smith" mods as well; if you're worried about affecting value by losing originality; I had my 8B rebuilt with the best of everything under the hood and it's one of the reissues VAC did in the 90's... these do come up for sale and no-one will shoot you down in flames for hot-rodding one
G
If I buy it, I think I'll buy the unmodified unit and just replace the electrolytics.
Scott
I'm a fan of the 8B. The answers are correct, make changes to an 8B and it (usually) reduces its resale value. But it also makes it sound better. No idea what Hovland changes are, but typical update is to recap, low noise diodes, coupling caps, replace out of spec resistors, driver tube changes (or just use I think they are E90's that sound so good).
So you end up paying a premium for an 8B, in some cases it is worth it, other times not. My experience is that it depends on system synergy. I tried a lot of amps before I settled on an 8B, but I use it with electrostatics which have an odd impedance curve. In this case, the 8B ended up beating out every other amplifier I tried.
So far, the 8B edges out my Mcintosh MC30, MC240, MC60 and MC275, but not by a whole lot. However, I made an easily-reversable mod to each of the Mac amps that replaces the !2AU7s with 6CG7s. I did A/B comparisons (with and without the mod on each channel on each amp)and the mod makes a very noticeable improvement in all of the Macs.
Scott
The problem with the 8b is it's both a collectors piece and a 55+ year old stereo.
The collector side would have you leave it stock. But it's also an amazing stereo. Unfortunately to use it, you need to have it restored.
Find a professional to do the work properly and USE it. That's what it was made for.
What speaks are you trying the amps with?
Here is some 8B trivia, hopefully correct, that has helped to make the 8B collectible. Sid Smith wound the prototype transformers. Marantz liked them, sent the drawings out (to I think Peerless). The transformers they wound did not sound as good. So Marantz ended up winding all 8B transformers in-house, under Sid's supervision.
Saul Marantz did an interview close to the end of his life, was asked what amp he had at home. He answered the 8B.
The 8B has a separate feedback winding. Some of the McIntosh amps do also, but there are a lot of amplifiers that don't. In the case of the 8B I'm guessing it helps it do well with the Electrostatics I'm using.
I'm using them on Bowers & Wilkins 803 Nautilus speakers. I've found them to be very revealing when evaluating the nuances of amps and preamps.
Scott
Those are great speakers. I'm a B&W fan, I bet that would be a good amp for those. Sounds like you are having fun with this. I have powered subs, so bass wasn't a concern for me. I did save the original coupling caps, in case I ever do want to put it back stock.
It's funny I don't remember the 8B having selenium diodes. I recall putting in low noise diodes and being able to hear the difference, but I remembered the ones that were in there were silicon.
Tubes made a big difference and coupling caps made a noticeable difference. I used a combination of K40Y and film coupling caps. I did increase PS capacitance, but not substantially.
Only the bias rectifier was selenium. The B+ ones are silicon.
Yes, it does sound great on B&Ws.
Scott
Nt
Viridian- I'm not sure I understand your response "Yes, they do. nt" to "My primary question is whether the Hovland modifications decrease the resale value of the 8B." Do you mean "Yes, they do"?
Scott
nt
That's what I thought. Thanks for your input. The consensus is universal that I should get the unmodified one.
Scott
It's a question that I deal with regularly when restoring, reconditioning, upgrading or modding gear. The answer usually depends on condition and if the piece is destined for the Asian or collector market or if it going to be a great daily driver for someone.
Having bought, and sold, a few 8Bs I don't much care for the sound, finding the stock amp bass light. Never did a full blown resto mod on one, just because I have never had a really ugly one. IMHO, and this is very subjective, there are better amps out there for the kind of money that the 8B commands.
One thing that I found is that you are responsible for any mods that are made and it will almost assuredly decrease the resale value as buyers question what was done. I do a lot of refurbishing work on tubes amps for other people and I cringe when I get one that has been modded. The biggest issue is no documentation of the mods and the quality of the work done.
I am not going to get the modded one in case I ever want to sell it. My goal is to make it my main listening amp in my hobby room so I want sound quality, but I don't think it could be that much better than what I'm hearing now. I am very pleased with its performance.
Interesting on your experience of the 8B being light on bass. To me, it seems to be about the same as my Mac tube amps, although the Mac amps seem to have a little more lower midrange. The 8B I'm auditioning still has the original power supply caps. I've found that replacing the tired old filter caps with new ones and increasing their value helps the bass response to some extent. The 8B has only 40uf for the filter cap that feeds the primaries of the output transformers. Increasing that is not really a "mod" and should help overall performance (or at least can't hurt).
Scott
.....that we are all going to have different takes on gear. Glad you have found your sweet spot.
But increasing power supply capacitance is a mod, as the amp will no longer be representative of the original schematic. Nothing wrong with that.
Increasing the capacitance is a totally reversable mod.
If you're a purist, replacing a selenium rectifier with a silicon one and adding a series resistor to provide the correct voltage technically makes it a modified unit because it no longer matches the schematic. Marantz most likely would have used higher capacitances in the power supply when the 8B was in production except for the high price and large size of higher capacitance cans in the days of yore. What they used nevertheless worked well, and that's what we have.
I think the mods that cause the devaluation are the ones involving significant circuit changes. Even a mediocre technician understands why someone increases the capacitor values in a power supply.
Scott
...those things are mods plain and simple. Reversible, sure, so what? Still mods. And sometimes, mods beget more mods, so if I were increasing capacitance in the power supply, I would also add an inrush current limiter, that was appropriately sized.Mod is not a dirty word, often we need to correct design flaws and problems with older material science in parts. Nothing wrong with that. It does tend to devalue the amp on the collector markets, but it can often be restored before sale. It is getting very hard to source some NOS parts that are 55 years old so true restoration has only become more challenging as the years go by.
Edits: 05/25/20
I believe it would be impossible to find NOS power supply can capacitors identical to the ones used in the 8B. Even if you did, they likely would be bad after sitting on the shelf for decades.
If you bought a '53 Corvette, would you put API SA oil in it just because that is what was used in 1953? No, you'd put in modern grade oil (API SN) to assure long life and better performance (SA oil is why car engines wore out after 60,000 miles years ago). Same thing with replacing parts in an amp or preamp. Keep it as original as possible, but replace the bad parts with good quality modern ones unless you just want it to sit on a shelf.
Scott
....to keep it on a shelf. I have been dealing with collectors in Japan, and more recently, South Korea, for over 30 years. There are car collectors that do exactly the same thing. Though, just guessing, it is probably hard to find gas and oil from 1953, LOL, and you really wouldn't want to turn the engine over with that junk in it.I have access to vintage can caps, and many can be reformed and are functional, but functional and performing to near original specs are miles apart, which is why restuffing can be a very attractive way to keep the original look while still providing a modicum of reliability.
Collecting is just a different part of the hobby. Many on this board deride it, but folks can spend their money any way they want as far as I am concerned. It's fine to appreciate the historical value, aesthetic and provenance of gear without actually wanting to play it. I don't imagine that many people are running down to the 7-11 for a pack of cigarettes in their Locomobiles at this stage of the game.
Edits: 05/25/20 05/25/20
Restuffing is a major pain, especially with painted cans such as on the 8B. I just mount the new caps inside the chassis. However, I know anal people would have a fit over that. I also know several antique radio collectors who hollow out their old wax capacitors and restuff them. I guess they sleep better at night knowing that the capacitors that no one will ever see look original. To each his own...
Scott
You're exactly right. Back in the day material technology was very different. Upping a 600v cap wasn't a simple matter. As glorious as the 8b is, it still had an selling price point.
I always wondered what Saul Marantz would have done with the 8b today????
I still say restore the 8b as close to original with some minor tweaking in cap values (as needed). As long as you're not reinventing the driver board or some stupid thing like that - go for it and enjoy it.
I wouldn't hesitate to buy one in which someone had upped the power supply capacitor values. However, tweaking the values of coupling or bypass capacitors is a totally different matter as is changing the circuitry.
Scott
Yes, that mod, as well as any other unknown modifications will decrease the value and or performance. Again, the 8b didn't have many problem points.
That is what I thought. The one with the tube adapters that allow use of 6AU6 in place of the 6BH6 does not permanently change it, but does seem to help the soundstage to some extent. I think that is the way to go.
Scott
Bob knows what he was doing. However, the 8B had very few short falls. I would get the unmolested version and have it professionally restored.This isn't a piece you should fool around with. It has a significant collectors value.
I did edit the post out of pure embarrassment. I apologize for the horrible posting error.
Edits: 05/25/20
After getting a lot of responses, I agree about getting an unmolested one.
Also, Robert Hovland is definitely still around. You can contact him via email at: roberthovland (at) earthlink (dot) net [replace the at with @ and the dot with .]
He will always reply if he receives your email and feels he can assist with your inquiries.
Scott
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