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i've nipped over from the vinyl forum to ask you guys advice on which vintage preamp with a tubed phono section to consider, i've done some searching in the archives,-& see the scott's & fishers get a big thumbs up for sound & value,any suggestions would be appreaciated--including modding/repairing/upgrading/& alterates, regards everybody ---& happy holidays.
Follow Ups:
thankyou everybody for the advice & ideas,--now i can start to streamline what my needs my be.
First & foremost --i enjoy the diy aspect.
i build my own turntables(this doesn't help with dangerous voltages in amps i know), how ever i'm prepared to take it slow & maybe start off with a refurbish of an old trashed unit.
Mainly i would just prefere something to use as a pre-amp -with the option of being able to add in other after market phono sections,older units do not provide much connectivety(this might be a problem but i'm not sure yet as i've sold all my past gear/& am starting from scratch/which is not a bad thing).
1)So an older unit that can be repaired & used or converted to a pre/ & upgraded.
2)A newer unit based on old designs/with more switching facilities.
3)A new kit.
4)To have the option of using different phono sections.
5)I plan on using solid state power amps.
I'm not really locked into anything just yet/i'm at the research stage.
thanks for the help so far--happy holidays everybody.
Hey,Well there are allot of options out there. Many have piped in with their comments. Most of these would not fit into a high resolution system. (I infer this is the type of system you are running.) Here are a few suggestions:
(1) Dynaco PAS. This is a good, decent unit. Updating parts and redoing the power supply will result in a very good performer for little money. The phon stage of this unit is not the end all, but it is a rather good standard from which to measure. Lots of inputs (and you can rig some more). The problem here is the low output impedence that will not match well with all amps.
It is worth noting that the Conrad Johnson preamps are very similiar in design to the PAS. Some of these add a cathode follower on the output. This would make the preamp capable of matching amps with lower input impedences. Given your solid state amps, it may be worth looking at the CJ's.
A cheaper solution would be a Eico HF-85. I am not sure of the output impedence on this one, but there is an extra tube compared to the PAS. The preamp is also point to point wiring. No crappy circuit boards. This would allow you to do some mods such as taking out the tone controls and installing a cathode follower output. The problem is that once you do all this you are going to wish you had nicer sounding tubes than the 12AX7's and, unfortainately, the power transformer will not allow it.
(2) Bottlehead Phono and Line preamps. Lots of info on the Bottlehead board about these. The drawback here is that is that these definately look DIY without any "modern" style chasis. This means you probably will want to get a aftermarket cabinet (see Bottlehead site). However, this set up would allow you to play around with phono stages.
I personally have an Eico HF-85 sitting (in parts) on my bench. I am considering putting in a new power transformer and installing the Bottlehead Foreplay circuit in place of the stock circuit. (I have a modded Foreplay and like it much). Some problems exist such as the need for new potentiators of the right value and shaft length.
It is also worth noting that several other companies sell preamp kit. However, I have no experience with these.
(3) Well Known Vintage Preamps. Well there are lots of them. Most suck compared to modern components. There have been a number of DIY driven improvements to tube preamps, including active loading, better power supplies, and parallel feed outputs. My best recomendation here would be the Fisher 400C. It has several shortcomings, but a very sweet midrange which mates well with dryer sounding amps. This pre is sort of a pain to work on but... it does sound good. I personally sold mine, but I still run the 80C (a very similiar mono preamp) as part of a mono system. I doubt I will ever part with it as both the line and phono stages are very nice. Yet I would say that my modded PAS phono stage is better.
(4) Total DIY. Venture over to Tube DIY and ask around. There are lots of possibilities and many tested circuits out there.
Take care,
Rodney
this helped very much,-i'm leaning towards the full diy--wether it be a complete modding of an old unit or a new kit that can be upgraded,there are so many routes to take--building a nice chassis is no problem for me as i have enough access to metal working & woodworking machinery---so i'm thinking of a rack mount vintage looking unit that looks brand new(if that makes any sense to you).
the pas creates some intrest for me --as like you said the phono section will probably be another out board unit(also diy i hope).
I'm pretty new to the diy electronics---so i need uncomplicated stuff to start off with ---maybe a pas mod might be the ticket.
thanks for the valuable info to yourself --& everybody else --------regards nigel.
...I have several circuit ideas (and some tried and true) looking for chasis. This is THE major sticking point right now between my hobby and my girfriend. I unfortanately have no metal working experience, but I have developed several ideas for chasis.Upgrades are a great way to get your feet wet, and a cheapo PAS mod would be a good reference for future activities. But really you will want to go to point to point wiring, better power supply, ect... I would recomend the RCA passive phono stage for this second step. Also I would suggest a full preamp (phono + line) and taking the power supply off board (seperate chasis). Spend some time on the power supply and overbuild it so you can play with lots of tubes. Also get a few B+ taps going, and pehaps a couple of channels. Then put the Foreplay circuit in the first chasis with your RCA phono circuit. I suspect this whole project would run in the $300 range, and would definitely sound nice.
I can certainly help you with the PAS phono stage, little money, good improvement tweaks.
i have more access to woodworking machinery than metalwork, although i could possibly get to use a break/bending station(bends custom sheet metal),as towards punching holes--well i have a large hole saw collection/access to a drill press & an old multi sheet metal punch.
anything else in woodworking for me is like scratching my butt(pretty easy) ive been a furniture maker for 20 years.----if you can lay out a chassis design via drafting table or autocad--the chances are i can get it made . a prototype of aluminum could be easier--as alumimum cuts on woodworking machinery.plus jigs & templates can be made for routers & drilling positions, i just need a decent set of drawings thats all.
I live in baltimore,maryland.
thanks again for the info.
feel free to email me.
I recently did up a PAS. I started with a rebuild/refresh of the stock circuitry. Then moved on to some simple mods...removal of tone controls...replacement volume pot...etc. Then I picked up Curcio's boards. If you buy just the boards and source the parts yourself the price ain't bad, especially if you have the tubes already.After the work is all said and done it isn't a PAS anymore. The other thing kept is the power transformer and chassis. A new heater transformer is installed and all voltages are regulated. Enough about the details though. The sound is quite good...good enough to give most any affordable preamp a serious run for it's money(I compared it head to head with a highly modded A.I. M3A and was very pleased with my work). And the work can be done in bits at a time to keep the budget in check.
If nothing else the phono board could be used by itself in another unit if you can supply the right B+. I had auditioned a fully tricked out Foreplay and IMHO it's not even remotely in the same league.
Just an idea to consider,
Russ
...much, much cheaper. Moreover, I really focused on the power supply and on the phono stage (as I was comparing some at the time). I think the line stage is basically a basket case. Sure you can get a little better performance with it (active loads or diode bias, removal of the tone controls, ect...), but basically your still left with 12AX7's. Sure you can add another tube (which requires a new power transformer), but by this time you are better off building from scratch. I am sure a RCA style passive phono stage into a Foreplay type circuit (also first described in the RCA manual, although not an exact match) will beat the pants off the PAS and many others. The price for this project would be under $250.I am not trying to slam the PAS. I just want to point out that it may be allot easier to scratch build rather than redesigning the PAS. You all know I love to modify things, but a total makeover is really not my personal approach to vintage equipment. Moreover, if this is your intent, you are much better building around the Eico HF-85 which has point to point wiring, more tube sockets and plenty of room.
Take care,
Rodney
...I live in Washington DC. My email is "drjrb2" at "yahoo" dot "com"
(Hopefully this protect me from the bots).Perhaps we can set something up so that you can hear some of the cicruits we have bee talking about. I have a all out Foreplay, modded PAS, HF-85, Fisher 80C, ect...
Take care,
Rodney
I have not heard any of the tube Mac or Marantz preamps ever sound really good. Noise levels are pretty high, detail pretty low, and in the middle of all that muddle, lovely mids. Same goes for Sherwood, Scott, etc. from the 50's and 60's. Admittedly, my Marantz experience is very limited, but I lived with 2 C22's for an extended period. I think them over-rated.Coming into more recent stuff, early C-J preamps weren't much better. Slightly better noise levels, and wonderful imaginging and sound-stage. Lousy dynamics -- the "PV" series up through the PV10 all seemed to compress everything.
The exception I've found are the late 1980's/early 1990's VTL preamps - Deluxe, Super Deluxe, and Ultimate. Lived with all of them, and recommend all highly. Their sound resembles the early Mac tube stuff, without the noise, with tremendous dynamics, and great soundstaging and imaging. Manufacturing quality is decidedly NOT up to Mac levels, and some pre-emptive maintenance is recommended. Great units for upgrades, and very easy to work on. The only preamps I've listened to that are markedly better are the Manley line, and with that we are into current production.
Not knowing your price range nor techinical abililty its hard to say. But for my money. FISHER 400C and or 400Cx
Hey nigelbetts,Well, there are lots of options, but quite frankly there is no way to make a recomendation without some more information.
What price range?
What amps will you be using?
Do you have a "high resolution" or "hi-fi" setup?
How much DIY work are you willing to do?
Basically any recomendation is meaningless unless one knows how the preamp will be used.
Happy Holidays,
Rodney
Hi,I see this question come up once in a while. I'm quite happy with my MX-110 tuner/pre-amp's phono section. Two phono inputs with level controls plus a good pre-amp and tuner to boot. They come up on eBay quite often so the prices are what I would call reasonable.
With older tubed equipment, if it hasn't been already, make sure its had the power supply electrlytic caps replaced and the unit checked out for proper operation.
Another thing to think about for vinyl is that older tube phono sections will generally be a bit noiser than newer semiconductor-type phonos - as always, your results may vary....
Hope that helps.
Cheers,
David
Nigel,I thought that you, and your twin Dual 701 'tables, moved back across the Pond, to England.
Whether you deal with a pre-amp, or an integrated; nearly all vintage units will need higher capacitance values, in the coulping caps. The cap values were picked to filter out turntable rumble. Killed the bass. Had to correct this issue in my Scotts, Fishers, and Dynas.
No matter what you pick, you need to measure the RIAA curve on the phono preamp. In the 60's and early 70's toillerances on these were pretty sloppy and a great deal of the difference between them is simply that the frequency response is noticeably different. Being + or - 1 dB off from the standard RIAA curve is not at all uncommon.Jerry
* HAPPY NEW YEAR *
I've used PAS 3-X with Teles', EICO ST-70 and currently Scott LK-48. IMO, the Eico has the best phono, followed by the Scott, with the PAS bringing up the rear. These are all tube regulated power supplies. A friend of mine was just telling me how much he's enjoying the ASL MiniPhono. Low gain ~30db but fairly inexpensive.
the fisher is excellent , the scott`s a good as well they are so close you can start arguments, but also the dynaco has a good phono sect. also dont forget about purchasing a phono stage you don`t have to rely on a manufactures idea of what is good , get the preamp that sounds good to you then add your own unit, i have a vintage sure unit with premium tubes and enjoy it. also i do love using the phono sect. of my hafler 110 just in to the phono out through the tape monitor into the amp, there i can also use my tone controls , for lesser quality recordings, me myself ,i am still in the middle, of weither tubed phono sect. make an improvement, i use both and enjoy both maybe a little to the solid state side, but i most definetly enjoy tube rectification, and output i`m just not certain the phono sect., is critical to the sound of the records ., but above all don`t limit yourself to tube when it comes to the phono,..... just my humble opinion........zman
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