| Runco990 |
I did a search, but didn't (as usual) come up with anything specific.
Now that I am loving my EL34 amp, I find myself in need of a phono pre-amp. Thinking of going tube, or am I wasting my time?
Is a $250 budget realistic? And, unless it's in a kit I can buy, I want a finished product. I'd like to listen to my records THIS year. :rolleyes:
Finding everything from scratch is out. (My second amp is another story :D)
I am trying to purposely avoid taking my denon SS preamp out of the closet. I am very pleased with the sound of my amp as it is, and don't want to add another stage of processing.
Most of you guys have been there already, so I feel it's best to just ask for advice.
Any thoughts please?
Marc |
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| SY |
| Start here: what sort of cartridge are you planning to use? |
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| Runco990 |
I have a Thorens TD-160 TT with a Shure M97x needle.
Good enough for me, and better than some of my records....
I HAVE to be mindful of what I spend, and right now sourcing parts for a pre-amp will take too long. Although I may do so LATER. (probably much later with my schedule....)
Thus a kit that I can assemble, or a pre-built will have to do for now.
I'd actually prefer a kit, though.
I'm hoping to keep it around $250 if possible, but may stretch it. The matching Ming-Da right now is $450, a bit steep considering I bought the power amp for that. Shipped. I have always used integrated amps, so I don't know if I'm really off base money wise here.
Granted, I see high end go for thousands, but that's TOTALLY out of my leauge.
As always, I really apreciate everyone that steps in to help and advise.
I'm much better versed in IC's and video than vintage audio. Still trying to figure out why I got started in this again.... must be a 40's thing.... |
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| lousymusician |
| The Bottlehead Seduction kit runs $279, seems to have a lot of fans. I've not heard one myself... |
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| phn |
If the Ming-Da is a power amp I recommend a preamp with integrated phono stage. A separate phono stage should only be used with an integrated amp.
The idea of a line stages/preamp without phono stage makes no sense. If you spin vinyl, you need one with a phono stage. If you don't spin vinyl, you don't need one. It's just a wast of money. Which, of course, makes lots of sense if you are dealer. Too many P.T. Barnums in the world. |
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| Runco990 |
The Ming-Da is an integrated amp. It has 2 line level inputs and a volume knob.
Looked at the bottlehead..... have to think about that. I seriously do not like the looks of it. I'd have to get a totally different enclosure, at least. Already at $350 or so with a nicer box....
Marc |
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| Eli Duttman |
Fancy cosmetics and low cost DON'T go together. A LOT can be done with the Seduction's looks, including hammertone paint on the chassis plate and stain on the alder base.
Yet another DIY option is Jim Hagerman's Cornet. |
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| bear |
My 2 cents worth...
Throw away the Shure.
They're all boom and sizzle, imho.
Try a good AT model in the moving magnet category, way better.
Then any phono stage will do for now.
Any.
Find an old tube receiver at a flea market or yard sale?
Buy an old Dynaco PAS preamp?
Or build up one of the many split passive designs that exist on the web.
There are PCBs online and on ebay that claim to have copied things like Marantz and McIntosh tube circuits - just build up the phono stage part??
The options are endless...
_-_-bear |
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| burnedfingers |
I'm in the same boat as you are. I have several turntables that are not fancy. One has a Stanton and the other an Audio Technica MM cart. I have been looking at several tube phono stages as well as a missed SS group buy PC board. I'm not against running a SS phono stage into my Aikido line stage for the desired result.
I will say this....stay away from the ebay PC phono stages from across the ocean as they are noisy and not worth the time. I personally would not recommend a dinosour like a Dynaco from the past.
Hagermans Cornet has caught my eye and I am waiting for someone from diy to purchase one and review it before I jump in head first.
May the tube "Gods" forgive me but I am thinking it might almost be easier to go the SS route then to keep banging my head against the wall looking at countless designs weighing the good and bad points. |
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| EC8010 |
| Burnedfingers: May you be boiled in oil! Your profile says "crazy for tubes" and you're suggesting squalid state? Shame on you! |
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| burnedfingers |
Well Sir, I have no excuse.
To be honest I don't know if I can make a phono stage that I could be proud of. I like octal tubes but some say they have a higher noise level. I am frightened of the gain needed in the stage because of noise that could come with it. I am very open to suggestions but would prefer a diy circuit as opposed to a kit.:o |
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| EC8010 |
| quote: | Originally posted by burnedfingers
To be honest I don't know if I can make a phono stage that I could be proud of. I like octal tubes but some say they have a higher noise level. |
You won't know until you try. You need low noise at the input stage, but provided that's done right, there's nothing to stop you using octals for the rest of the circuit. The loctal 3A/167M would make a superb input valve if only you could find some. Triode-strapped EF184 would be quiet (and dirt cheap). Follow it up with 12SN7 or 14N7 (far cheaper than their 6.3V equivalents). |
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| burnedfingers |
Sir,
You have motivated me to at least give it a good try. Being surrounded by some of the very best in the field how can I fail? |
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| EC8010 |
| Excellent, split RIAA, DC heaters, star earthing and you can't go far wrong. |
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| phn |
Good luck with the 3A/167M. It's rare and people know it's a Western Electric 437A with a loctal socket. Try wrestle that one away from the Japanese. :D
Why not EC8010 and 12B4? No gain is needed after the EC8010. Both transformer-coupled. You could replace the EC8010 with D3a. |
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| burnedfingers |
| What is a D3a? |
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| SY |
| quote: | Originally posted by EC8010
Excellent, split RIAA, DC heaters, star earthing and you can't go far wrong. |
Eh, get the first stage gain nice and high and you don't have a noise penalty for doing the RIAA in one big clump. |
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| SY |
| quote: | Originally posted by burnedfingers
What is a D3a? |
We don't talk about that one in public. ;)
It's a high gm pentode which forms a high mu high gm triode when the screen is connected to the plate. |
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| Runco990 |
Okayyy..... so I bought a cheap SS phono preamp JUST so I can use my TT in the meantime.
Decided to build one after all. Figure it's a good start.
I have a nice stash of mullard 12ax7's, 12at7's and 12au7's.
All tested good. Found sockets, chassis, etc. Only need Iron and a diagram.
Now if some kind soul could lead me to a proper transformer and a schematic, I think I can handle it from there.
Where the heck DO you guys get your NEW iron? Don't have time to look for used right now.
Thanks.
P.S. I actually have a few bags full of different tubes, so if someone has a better suggestion, I can check if I already have it.
Marc |
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| SY |
| For a power transformer, I'd look to surplus. Ebay is your friend. Herbach & Rademan had some likely looking candidates, too, when I was poking around earlier today. For new, Edcor is inexpensive and looks pretty good. |
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| EC8010 |
| For an HT transformer, look out an old bathroom light fitting with shaver socket. The (typically 20VA) isolating transformer can be used with a voltage doubler to give 320V. For heaters, look for any old EI transformer that hasn't been lacquered, take the laminations out, unwind the secondaries (counting the turns as they come off), measure the wire diameter and rewind for whatever voltages you need. Salvage common mode chokes from computer power supplies. |
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| chrisb |
If it's not too late to echo a couple of recommendations made earlier, I can highly recommend the Seduction. A buddy of mine built one a year or so back, as part of a now full Bottlehead system, and I've had the opportunity to hear, as well as several other much more expensive tube based phono/line stages (2 different examples of K&K, as well as the Hagerman Coronet) For my money the only FIY product that showed the Seduction the door was the multiple times more costly K&K.
If I hadn't previously finished my own scratch-built phono stage (for much higher cost in the end), I'd start with the base Seduction, and tweak with upscale component parts after a few months of burn-in.
As Eli noted, the base cosmetics of (any of) the Bottlehead products is not their strongest selling point, but the only limitation to customization is your imagination. |
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| phn |
| Search this forum or google. Lots of them out there. |
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| Runco990 |
| quote: | Originally posted by EC8010
For an HT transformer, look out an old bathroom light fitting with shaver socket. The (typically 20VA) isolating transformer can be used with a voltage doubler to give 320V. For heaters, look for any old EI transformer that hasn't been lacquered, take the laminations out, unwind the secondaries (counting the turns as they come off), measure the wire diameter and rewind for whatever voltages you need. Salvage common mode chokes from computer power supplies. |
WHOA! Guys...... I am NOT in the wind-your-own transformer stage here....:xeye:
That's a little too advanced for me. I'll leave that for later..... much later.... :D
Looking for a suitable transformer that's in one piece, thank you.
Marc |
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| Eli Duttman |
| quote: | | Looking for a suitable transformer that's in one piece, thank you. |
$18.97 gets you Allied Electronics stock # 227-0067, which has a 230-0-230 V. rectifier winding rated for 50 mA. of B+ and a 2.5 A./6.3 V. filament winding. Rectify the B+ with a 7Y4 or 6X4. The filament winding provides AC for the rectifier and also feeds a "full wave" voltage doubler made from 2X substantial Schottky diodes and 2X large 'lytics. Follow the doubler stack with a 7812 3 terminal regulator IC. 2X 12AX7s draw 300 mA. @ 12 V., which is easy for the IC if it's well heatsinked. |
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| Runco990 |
| quote: | Originally posted by chrisb
If it's not too late to echo a couple of recommendations made earlier, I can highly recommend the Seduction. A buddy of mine built one a year or so back, as part of a now full Bottlehead system, and I've had the opportunity to hear, as well as several other much more expensive tube based phono/line stages (2 different examples of K&K, as well as the Hagerman Coronet) For my money the only FIY product that showed the Seduction the door was the multiple times more costly K&K.
If I hadn't previously finished my own scratch-built phono stage (for much higher cost in the end), I'd start with the base Seduction, and tweak with upscale component parts after a few months of burn-in.
As Eli noted, the base cosmetics of (any of) the Bottlehead products is not their strongest selling point, but the only limitation to customization is your imagination. |
Still considering that. True, I can stuff it into my own cabinet.
Marc |
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| jduffy |
I dig phono preamp threads. Part science and part voodoo. Here's mine from a little while back. Some great info for sure. I'm working on getting my parts together so I can build mine.
http://www.diyaudio.com/forums/show...7548&highlight=
Good luck with your choice(s). |
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| planet10 |
I'm in late, but given the original question, this ready to go puppy for $250 has received universal praise in the media (i haven't seen or heard one)
http://www.needledoctor.com/Bellari...=2&category=401
As the feedback RIAA & the low voltage supply have to compromise it somewhat, for not much more i'd personally get the Seduction and not just because the picture is better...
dave |
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