Thoughts on Marantz 7 Tube Preamp Kit?

Anyone had their ears on them? They can be had for cheap so I am not expecting a world beater, just something to add some flavor into the mix.
Link: https://www.ebay.com/i/162328754380?chn=ps
Finished one here: https://www.ebay.com/i/132598587751?rt=nc&_trkparms=aid=222007&algo=SIM.MBE&ao=1&asc=20160908110712&meid=e0712a2f23684aa7b8710a85cee1efcf&pid=100677&rk=10&rkt=30&sd=162328754380&itm=132598587751
Link: https://www.ebay.com/i/162328754380?chn=ps
Finished one here: https://www.ebay.com/i/132598587751?rt=nc&_trkparms=aid=222007&algo=SIM.MBE&ao=1&asc=20160908110712&meid=e0712a2f23684aa7b8710a85cee1efcf&pid=100677&rk=10&rkt=30&sd=162328754380&itm=132598587751
Just a dude doing dude-ly things
"Temptation is the manifestation of desire which equals necessity." - Mikey081057
" I have always had a champange taste with a beer budget" - Rick88
"Just because the thread is getting views don't mean much .. I like a good train wreck doesn't mean i want to be in one..." - pitdogg2
"Those that don't know, don't know that they don't know." - heiney9
"Audiophiles are the male equivalent of cat ladies." - Audiokarma Member
"Temptation is the manifestation of desire which equals necessity." - Mikey081057
" I have always had a champange taste with a beer budget" - Rick88
"Just because the thread is getting views don't mean much .. I like a good train wreck doesn't mean i want to be in one..." - pitdogg2
"Those that don't know, don't know that they don't know." - heiney9
"Audiophiles are the male equivalent of cat ladies." - Audiokarma Member
Comments
But if you feel like spending some money, go for it.
I trust what you say Doc. I was looking at some of the cheaper Bottlehead models too just a bit farther off than a quick premade kit.
"Temptation is the manifestation of desire which equals necessity." - Mikey081057
" I have always had a champange taste with a beer budget" - Rick88
"Just because the thread is getting views don't mean much .. I like a good train wreck doesn't mean i want to be in one..." - pitdogg2
"Those that don't know, don't know that they don't know." - heiney9
"Audiophiles are the male equivalent of cat ladies." - Audiokarma Member
If you don't need a lot of gain, the goofy little battery-powered BH "Quickie" is not bad -- the only trick is finding 3S4s that aren't too microphonic.
(from the BH website)
One came to visit here one day and it sounded mighty fine driving the "Simple 2A3" amplifier.
photo from http://forum.polkaudio.com/discussion/26433/show-me-your-****-embly-and-let-me-get-in-your-guts-baby/p36
(Vanilla's censor may butcher the URL
Which reminds me -- one of these days I need to build the Quickie that's sittin' in a box in the closet, not ten feet from where I am sittin' as I type this
In layman's terms what applications would I need more gain over a lower gain?
"Temptation is the manifestation of desire which equals necessity." - Mikey081057
" I have always had a champange taste with a beer budget" - Rick88
"Just because the thread is getting views don't mean much .. I like a good train wreck doesn't mean i want to be in one..." - pitdogg2
"Those that don't know, don't know that they don't know." - heiney9
"Audiophiles are the male equivalent of cat ladies." - Audiokarma Member
Ha ha ha Doc layman's terms ....... yea maybe the first 5 words.
LOL
(how was that?)
"Temptation is the manifestation of desire which equals necessity." - Mikey081057
" I have always had a champange taste with a beer budget" - Rick88
"Just because the thread is getting views don't mean much .. I like a good train wreck doesn't mean i want to be in one..." - pitdogg2
"Those that don't know, don't know that they don't know." - heiney9
"Audiophiles are the male equivalent of cat ladies." - Audiokarma Member
http://wallofsound.ca/audioreviews/review-elekit-tu-8500-tube-preamplifier-kit/
Or Bottle Head has some great units too.
H9
Pass Aleph 30 | EE Avant Pre | EE Mini Max Plus DAC | MIT Shotgun S3 | MIT Z P/C's | updated SDA 1C| SQ Box Touch/Welbourne Labs P/S- Tubes add soul!
The Elekit stuff is generally quite nice -- at that price point, there are (or at least were) other options, too. Besides Bottlehead (which we've both mentioned), e.g., there's Bruce Rozenblit's Grounded Grid preamp.
http://www.transcendentsound.com/Transcendent_Sound_Grounded_Grid_Preamp.html
(borrowed photo -- this one has some upgrades relative to stock, e.g., some coupling capacitors)
Interestingly/ironically, there are Asian-sourced, very inexpensive Grounded Grid preamp knockoffs out there in cyberspace -- they are rather literal rip-offs of the real thing.
http://www.tubes4hifi.com/pre11.htm#SP14
Gettin' into some fairly serious money, though -- so, of course, there are ever-more options as the budget goes up!
1) It was your preamp kit build from which I borrowed the photo posted earlier in this thread!
(thanks!)
2) Thanks for mentioning that the good news about 3S4s is that they're not very expensive! I believe I forgot to mention that part.
2) Thanks for mentioning that the good news about 3S4s is that they're not very expensive! I believe I forgot to mention that part.
[/quote]
I'm just thinking out loud here; if a particular type of tube is known to be problematic then why not avoid them altogether even if they are inexpensive?
7199s are notorious for microphonics -- and not particularly common nor cheap.
As to Doc Bottlehead and the 3S4. Who knows why the tube was chosen, but I assume he/they chose to use them because they are cheap, plentiful and they're designed to be used in battery powered equipment (e.g., the portable and "farm radios" of long ago), and they are good performing, linear triodes.
Then you say the 3S4 are "good performing linear triodes". If they're microphonic wouldn't that take the "good performing" part out of the equation? Are there substitutions for these tubes that don't have problems?
I'm not trying to be argumentative just trying to understand the justification of using a problematic tube or for that matter anything that has a known issue.
How long do you normally go without having to change the batteries. Something to me seems silly about battery operated Hifi equipment ha!
"Temptation is the manifestation of desire which equals necessity." - Mikey081057
" I have always had a champange taste with a beer budget" - Rick88
"Just because the thread is getting views don't mean much .. I like a good train wreck doesn't mean i want to be in one..." - pitdogg2
"Those that don't know, don't know that they don't know." - heiney9
"Audiophiles are the male equivalent of cat ladies." - Audiokarma Member
Good tube with, perhaps, poor QC. Throw away the bad ones.
You'd have to ask David Hafler about why he/they chose to use 7199s -- he's on the other side of the rainbow bridge now, though, unfortunately.
Generally, I think choices are made in sort of a net-benefit manner. If the pluses are felt (objectively or subjectively) to outweigh the minuses, the net result may be considered good.
Heck, people still buy Chrysler FCA products.
The batteries last around 150 hours. I am not an expert on battery operated amps and pre amps, but I think someone can chime in on the benefits of battery power. I chose this kit because it was my first attempt at a build and being battery powered I had less of a chance of an electric jolt and magic smoke.
In a DC powered (analog) device, it could be argued that the only AC in the circuit is the signal -- all of the infrastructure is pure DC. In theory, the best situation imaginable.
There've been a few battery-powered line-level preamps and (particularly) phono preamps.
Sutherland comes to mind, e.g.
Other than heating the filaments, the current requirements aren't bad for a preamp.
Battery powered transistor devices probably make incrementally more sense, though, of course -- but that's another topic entirely
In total fairness, it's been pointed out to me in past discussions that the noise level of a battery powered component won't necessarily be vanishingly low -- at some level, a battery will manifest some "chemical noise" (but we're getting into pretty esoteric territory).
Truth be told, though, a decommissioned battery pack from a hybrid or electric car would probably be a more pragmatic option.
I assume that the four nine volt batteries are wired to provide 36 VDC.
It might be argued that a hybrid P/S scheme (i.e., rechargeable batteries that can be trickle-charged when not in use) might be the most practical "solution" to the "ephemeral"
Go outside! Get some air!
Indeed -- s'posed to be eighty degrees today -- I am in fact gettin' ready to go out and start tilling the good earth.
Right ? The Professor has been cooped up inside far too long.
Sony 850c 4k
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Polk Sig. 20's
Polk FX500 surrounds
Cables-
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Acoustic zen Matrix 2 IC's
Wireworld eclipse 7 ic's
Audio metallurgy ga-o digital cable
Kitchen
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B&k 1420
lsi 9's
I am now rehydrating on the porch, thank you very much.
(artist's conception of what the porch will look like again in a few months
http://oddwattaudio.com/owforewatt.html
these guys came to the lone star audio fest for a couple of years.
Preamp: deHavilland Ultraverve 3
Transport/Dac: L.K.S MH-DA004, Cayin Venus cd-100i, Musical Paradise mp-d2 mkI,
Musical Paradise mp-d2 mkIII
Speakers: Rosso Fiorentino Volterra II
Speaker Cables: Organic Audio Organic Reference 2, Analysis Plus Black Mesh Oval 9,
Cerious Technologies Graphene Extreme
Interconnects: Argento Organic Reference 2, Argento Organic 2, Gabriel Gold Reckoning
Power Cables by: Cullen Cables, 6sons Audio, Swiss Cables
Neat-o. New to me (or maybe I've just forgotten about 'em
Thanks for the link.
I didn't see a photo on the site of the innards -- but I shall google presently
One is most curious -- as the price appears to be very right.
I think this is a picture of the insides.
https://www.bing.com/images/search?view=detailV2&ccid=xhoXX689&id=B149BBDE3C7AFD8B5B12CDF737410867D102DC9D&thid=OIP.xhoXX6893_6nUsghLs2xUgHaFd&mediaurl=http://diyaudioprojects.com/Tubes/ECC802S-ECC82-12AU7-Tube-SRPP-Preamp/DIY-ECC802S-Tube-SRPP-Preamplifier.jpg&exph=571&expw=775&q=forewatt+preamplifier&simid=607987691471635551&selectedindex=5&qpvt=forewatt+preamplifier&ajaxhist=0
Preamp: deHavilland Ultraverve 3
Transport/Dac: L.K.S MH-DA004, Cayin Venus cd-100i, Musical Paradise mp-d2 mkI,
Musical Paradise mp-d2 mkIII
Speakers: Rosso Fiorentino Volterra II
Speaker Cables: Organic Audio Organic Reference 2, Analysis Plus Black Mesh Oval 9,
Cerious Technologies Graphene Extreme
Interconnects: Argento Organic Reference 2, Argento Organic 2, Gabriel Gold Reckoning
Power Cables by: Cullen Cables, 6sons Audio, Swiss Cables
It's helpful, but a plain-vanilla photo of the kit innards would be nice to see (and I couldn't find one). Is it based on PC boards, or perfboard or P to P? The web image has PC boards & perfboard.
And design is often pretty poor. There's lot's of kit based stuff online that's not
going to sound bad or burn the house down.