Oddity Archive: Episode 136.5 - Ben’s Junk: Realistic Phono Pre-Amp (Model 42-2109)
Вставка
- Опубліковано 11 вер 2024
- Taking a look at an external preamp for the turntable-largely only because the cool kids are into it.
Visit our website at www.oddityarchi...
Social Media:
Facebook: / oddityarchive
Twitter: @oddityarchive
Help out the Archive by making a monthly donation to our ongoing Patreon campaign. Visit the campaign at / oddityarchive
Hi Ben, I think it's all been pretty much covered by other comments, but I would like to add my voice to those saying that the preamp, as well as boosting the gain, also applies the RIAA EQ curve, which is designed to be the exact inverse of the EQ curve that was used when the record disc was mastered. When cutting the disc, the bass level was reduced, so as to create a narrower groove pattern, which avoids the potential problem of grooves overlapping in the heavier bass sections, which would cause the stylus to skip grooves, as well as taking up more of the valuable and limited real estate on the surface of the disc. The pre amp boosts the bass to restore the original sound. I have a battery operated Realistic 42-8930, which I need to connect my turntable to my Marantz surround AV amplifier, which doesn't have a dedicated phono input, so I use the Minidisc input instead. Without the preamp, the sound is very weak and lacking in bass.
One of the main functions of a turntable pre-amp back in the day was to apply the "RIAA Equalization Curve". Records are "equalized" oddly to account for the physical limitations of the media. I'm not sure what the modern "hipster" turntables today do. My guess is the "non-audiophile" ones will include circuitry to do that.
Most likely the pre-amp will apply this curve: en.wikipedia.org/wiki/RIAA_equalization
The "hipster" ones probably use cheap cartridges that usually give a higher output signal but are prone to render "scratchy" noise like an old dirty potentiometer or easily break, even the pick ups break easily. Usually the cartridges that need preamps are more expensive but give you the best quality.
That's a phono preamp. It's needed by those that want to play records. It has nothing to do with boosting levels. If your equipment has no phono stage it can't play records
Cheap turntable use Cheap ceramic phono cartridge those do not use RIAA preamps. But they need to match impedance with the input or the high impedance of the cartridge will create a high pass filter and the bass will be affected. That is why crosley TTs sound bad with no bass. In modern equipment there is no easy way to fix it. There are DIY solutions with transistors and opamps.
Well stated. That's actually it primary purpose. That shitty cart that the TT-USB ships with insures that it's "Garbage -in > Garbage Out" .
@@davidm.27 This is Brian. They had no predilection for giving an riaa level. They were only functional to boost the preamplification to match a magnetic cartridge to a ceramic input or just an Aux. Input. Use one of these (on a mag phono cart.) in a tape monitor input on an older receiver and the bass would probably blow your speakers if not turned off. To experiment with this equipment is an education in itself.
A phono pre amp is used to boost the signal from a magentic cartidge up to line level and to apply the correct eq. listening via the preamp connected to an aux (line) input on your amp it should sound the same as your built in pre-amp phono input if you have one because it's doing the same job as the built in pre-amp! If you connect your magentic pick-up into a line amp without the pre-amp it'll sound really ueit and lackin gin bass.
The earth connection is essential for connecting a magentic pick-up. I guess you left your deck connected via your existing amp. The in/out sockets and earth tag are all you get on pre-amps - well and a power line of course and perhaps an LED to show it's on.
I use one because the vice old amp I used to use didn't have a built in preamp, although the repalcement amp does. I still use it because I can have to record deck some distance from the amp, which isn't advisable using the magentic input
I just have a middle of the road turntable I've been using for the past 10 years that cost about $150 that has the built in preamp. I have it hooked into my Dolby prologic II receiver and I don't have many complaints. It actually sounds pretty spectacular!
That Realistic preamp actually sounds pretty good and outperforms preamps costing several hundred. I hunted down three myself. They sound almost as nice as the Marantz 7c I love so much. You won't get much of an improvement because you're starting with trash to begin with. That Numark comes with a cartridge (red/black) that literally sells for less than $1.50 on ebay. You can't polish a turd my friend.
I am glad you mentioned this - it was a gem of a design. It gave my Audible Illusion 2B a run for the money back in the early 80's. Soundtage was better on the modulus , but the sound had a gray cast. I suppose not a fan of 6DJ8 tube in this circuit. The Realistic, on the other hand was very sweet and had nice bass drive. It did, though, have a narrow soundstage. I always wanted to build a bigger external power supply for that circuit. But I lost the unit in a move. - Sandy
Searches for "Stay as you are" by Joe Egan just went up 9000%
I've just bought it on ebay after seeing Ben's junk Nagaoka MP110 cart playing Maker of the make
With a simple turntable with built in preamp you won't hear much difference with a cheap preamp. The only reason for using it, is when you have a normal turntable and want to hook it up to a amp without phono input, or to your computer.
With a very good turntable and a very good preamp the difference in quality is of course striking.
Furthermore, typically a line input has an impedance of about 10K while a dynamic phono cartridge needs 47k. Load it too heavily, and sound quality will degrade.
This is Brian Kim Keenan. Do I have to educate everyone on a not so distant past? Are all your parents, aunts, uncles, etc. In a fog or drug induced coma or something? Here's the scoop.. Phono preamps like the one you show were used to make a magnetic phono cartridge usable in a ceramic phono input. People would have cheap department store stereos and they either had a ceramic phono input or just an Aux. input. It you didn't have this unit, your upgrade to a Garrard turntable with a shure magnetic cartridge wouldn't work. Although the unit you show was about 24 dollars new, , more economical units sold for 10 dollars. And they all worked pretty good. I'm using the one you show here on the front aux jack on my newer Denon receiver so I can have 2 phono inputs instead of 1. Works great. After reading the reviews of modern phono preamps, I would suggest one of these dinosaurs. I believe they are better and worry free.
It is either July 1978 or 1988, most likely 1988, according to the 7A8 date code on the back. RS sold these well into the 90s.
Six minutes I won’t get back
My turntable died years ago, but I still have my Realistic pre-amp from the early 80s. I spent most of my money on the linear tracking turntable then discovered I needed to spend more on one of these so I could hear the records. I also had a SoundDesign stereo so that may be why I needed this.
The 7A8 date code on the back means July of some year ending in 8 (likely either 1978 or 1988).
And there's a different phono pre-amps for different type of cartridges. Moving coil, vs ceramic, etc.
In 1988 , Radio Shack was still having it ... i saw it on their 87-88 Catalog !
A friend and I used to have this very model. Preamps were built into amplifiers, but we wanted to mix from two turntables, so we needed this preamp to go directly from the second turntable to the mixer. Today, you need one if neither your turntable nor your amp has a built-in preamp. From your narrration, it wasn't clear that you understood this.
I'm well aware of it. The main thrust of this video was in response to the trend of people using external pre-amps, just because they can.
This is actually a very nice sounding phono stage, I would rather it to a Project Phono Box but using such low end gear behind it you are not going to hear it sing
My understanding is that all that is for is if your amp doesn't have phono input. Shouldn't do anything to the sound. Of course it will add a little distortion or maybe alot depending on the quality. I have had luck with using the cheapest mixer on a high end system and it sounded the same as if the turntable was plugged directly into the phono in on the amp. You can get those with tube which will add that 6th harmonic over tone to make it a warm sound but as fr as increasing sound quality you really want a good one not some cheap ebay special where none of the components are matched and the tolerances are all over the map.
I'm by no means an audio geek, but I've been enjoying OA for a while now and thought it was time I chucked out a comment ;-)
I have always been under the impression that, as well as amplifying the signal, 'proper' phono pre-amps also did some form of EQ - that's as far as my knowledge goes, but a quick look through previous comments suggests that I'm not alone in that impression. I think cheaper amps would sometimes skimp on components for their phono inputs (if not miss them out altogether), essentially leaving a line input without proper signal amplification and/or EQ.
I had a little Realistic battery powered phono amp (which I guess dated from the late 80's/early 90's (although IIRC it still proudly proclaimed 'Solid State' on it), and remember a subjective improvement when using turntables on line inputs, and on quite a few 'phono' inputs, although not all. If your amp has the correct phono circuitry (and I'm quite sure it does!), then perhaps the pre-amp and your phono input were doing pretty much the same thing, hence the lack of noticable difference? I wonder, did you try plugging your pre-amp into the phono input with phono selected...I'm guessing the levels would be quite high, but perhaps it would make any EQ somewhat more obvious?
I also wonder if you there isn't a piece of software or plugin around that could give you a kind of 'frequency histogram' - a kind of spectrum analyser that would listen for the peak level at certain frequencies, but across a whole sample, as opposed to most SA PLM which reset the peaks quite quickly - surely differences here would be indication of EQ (or a crappy amp) in the line? I guess you could measure other things, like how often a certain frequency is detected, but then we're talking about the frequencies of frequencies, and that makes my head hurt.. ;-)
OK, well thats my OA comment quota filled for the next couple of years, but I welcome discussion and corrections! Also, if the Chief Archivist Himself is reading, I respectfully salute you, and sincerely encourage your efforts (Need Moar Videos! ;-) )...Also know that I am captivated by Pavanned, and wonder if you have other work available...?
Thanks for reading!
My musical back catalog is at benminnotte.bandamp.com
I have the same model Realistic phono preamp and it does to a better job than the built in phono stage in my 2018 sony entry levelish 2 chanel stereo receiver. The old Radio Shack phono preamp is slightly louder . I don't know if I can do a blind test and compare . What I do know is that hifi manufacturers these days focus less on fidelity unless it's the high end audio .
I had a tuner with 3 'phono' level inputs (an old McIntosh brand classic monster). I guess some people might have multiple turntables and not enough inputs? Also, while the stereo might be able to overcome the low level on the line, perhaps you would want the preamp for your recording pass through to tape?
I actually had some adjustable pre-amps that belonged to my uncle, I used one for the VCR's audio out into the speakers because I hated having to jump the volume around between radio, TV, CD, and Tape.
I've seen a commercial grade on at a local radio station (I did some computer type stuff for them) because all the board inputs were either balanced microphone or line. No phono level into the board. It wasn't anything special though, really.
This well exceeds the sound quality of most op amp based preamps. It uses rare Japanese transistors. It's problems are lack of gain and true dynamics but you will not better it with any or the current batch of Ss phono stages unless you spend a lot.
The TC-750 is a fully transistor design that sounds very good for $50, I have the TC-778 that has flat treble curve for 1920s 78 playback, after seeing mods on superaudiobestfriends, I changed out the electro coupling caps for 1uF WIMA which made it sound even clearer than before
You should had made a research about phono pre-amps first. Probably you didn't need it before because your turntables either had a built-in pre amp, didn't had a magnetic cartridge or your amp had a dedicated phono input that pre-amp'd the signal.
You definitely need one of those if you want to use a pro or semi-pro turntable with a magnetic cartridge in a modern sound equipment. They should sell these again.
I have one, not a bad budget pre amp, then again i'm 55 , and remember those days, they cost about 30 bucks in the 80's .
Ahhh, these millenials , nuff said on that.
i have one and THEY WORK and i need another one
So would you rather be a tube guy or solid state guy if you had the choice of phono preamp?
Blim The Toolman I hear tube pre amps have a "warmer" sound! However I hear the take up a bit more power and im the one who pays the power bill. But if I came across one for a good price I'd totally buy one!
@@jeenkzk5919 The power consumption on tube pre isn't that much greater than SS, It is the power tube amps that really guzzle much more power than SS
The built 8n phono preamp sounds much worse.
Hamsters do have lips.
I would love to see the circuitry inside this 1970's case, although I can pretty much imagine what it would look like. Lots of enormous through-hole passive components with a couple of transistors to do the actual amplification.
The idea is supposed to be the separate pre-amps you can buy will do their job better than the built-in pre-amps that sit between the Phono-In socket and the main amplifier physically within your audio deck. You probably don't want to connect an external turntable directly to Line-In without a pre-amp. The sound will be horrible and tinny more than likely, depending if the turntable already outputs pre-amplified and equalized line signals. If it _does_ then there either won't be any noticeable difference at all or possibly it could corrupt the signal somewhat if your 'Realistic' pre-amp is as shoddy as a lot of Tandy stuff was in Britain.
The first episode on laserkaraoke was blocked, figured I'd let you know
Yes. Yes it was. Has been for some time. It's on another website now. (vid. me/ moreOALostEpisodes - remove spaces)
OddityArchive Thank you, and on the topic of amplifiers, i had an amplifier that worked with the Nintendo DS, i have no idea why that was a thing, i bought it since i was curious
Hey Ben, I'm thinking of getting a record player. What would you recommend?
Skittle Jamz
If you’re buying new: U-Turn Orbit or Audio-Technica LP120
Used (usually cheaper and better): Anything 70s or 80s and made of metal or wood (Pioneer, Technics, Dual, Sony, Yamaha, etc.). You’ll just need a new belt/cartridge/receiver w/ phono, unless you have an audio shop or record store selling refurbished bundles near you
I've been considering a new turntable myself lately. Either an Audio Technica LP120 or a good, vari-speed, direct-drive vintage turntable are what I've been looking at.
OddityArchive For a cartridge I can’t recommend highly enough the Shure M35X: affordable, great tonality, and completely eliminates sibilance and inner-groove distortion (its tracking is incredible for a cartridge of its type honestly), and given that it’s a DJ cartridge it can handle beat-up records too.
I’ve got it on a big ol’ wooden beastly semi-auto Pioneer and it’s great enough that I feel I won’t be upgrading for a long while
I'm seconding the Audio-Technica LP120 if you're buying new. Purchased one to replace a well-loved Numark that succumbed to age and I've been very happy with it. (And, of course, no pre-amp required.)
I have been lucky to find an old Technics SL-1600 in the trash - still fully operational - but the trade off is spending a little time and cash getting it back in shape (replace the stylus even if it *seems* fine.)
TeeVee Games There’s been a lot of talk amongst audiophiles that the pre-amp circuitry in the LP-120 is so low quality that it makes the sound quality worse even if you turn it off and don’t use it (it’s said to make the tone duller and lacking in high-end) so a lot of people open the thing up and rip it out. Other than that it’s a well-made thing though, and even without modification I think it would be better than what Ben’s using now.