ST70/quickie/phono pre

Remoter · 6259

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Offline Remoter

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on: April 26, 2013, 04:18:56 AM
Hi -
I'm new to the Bottlehead community and I have a couple of general questions.
I have a Dynaco ST70 running through a ss Sansui 3000 using its pre out function. It actually sounds pretty good - but certainly no sonic magic occurring here. The vast majority of the time this setup is used for vinyl. 
I ordered a Quickie w/upgrade last week and look forward to receiving that little bugger (actually I find myself just a bit giddy with anticipation but I wont talk about that here lest I shatter my manly veneer)
Okay, question 1.
If I were to route Sansui  - quickie - ST70 did I create a tube(ish) phono preamp or buffer for $140? Should I expect improvement in musicality with this setup?
2. I am looking for a tube MM phono preamp and asking for advise.
I can get a modded/restored Dynaco PAS 3x preamp, which of course is the preamp developed for the ST70 for $400 to $500.
Or, do I get the BH Reduction for $300 presumably taking advantage of 60 years of advancement in this 100 year old technology.
Although there is something to be said for a period correct amp/pre setup and it does appeal to me, ultimately I am less concerned with that than I am with getting the best sound/value that I can get with this amp.
What to do?
On a side note, I have been haunting the BH forum for a few months (perhaps you noticed , visitor - that was me!) and I have a couple of observations. First the depth of knowledge on this forum is truly impressive -  secondly the willingness to share that knowledge is pretty cool. This forum is what ultimately parted me from my money when I ordered the quickie. Just the beginning??????



Offline Paul Joppa

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Reply #1 on: April 26, 2013, 04:44:43 AM
What follows is just my opinion when it comes to perceived sound - YMMV and all that stuff. Naturally I prefer my designs sonically - but nobody hears exactly what someone else does, so trust your own ears!

When you add a tube stage to a chain of components, you can mask some problems with tubey distortion (second harmonic) and it may sound warmer; sometimes it reduces the nasty artifacts of digital sources. But it does not get rid of the problems in the chain, and can only reduce the resolution.

The Dyna preamp uses feedback to get the RIAA equalization. The ST-70 also uses plenty of feedback. To my ear, feedback sucks a lot of the life out of music, which is why I prefer SET amps with no feedback. The Reduction is a zero feedback RIAA preamp with passive equalization. If you haunt the web forums you will often see references to the classic RCA phono preamp circuit; the Seduction/Reduction is my take on a modern version of that classic design.

Paul Joppa


Offline saildoctor

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Reply #2 on: April 26, 2013, 05:32:22 AM
FWIW I have a heavily modded seduction and still I think I will be getting a reduction.  There's a really good deal on the preorder right now, I know it is going to sound great even in stock form since it's mostly the same but with improvements over the seduction.  And uh, hopefully roomy enough underneath for some more mods! :) 

Kerry Sherwin

45 Paramounts, 6SN7 Extended FPIII, OC3 regulated Seduction
Blumenstein Orca Deluxe / 2x Orca Subs
VPI Classic / ADC CD-100x


4krow

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Reply #3 on: April 26, 2013, 05:42:58 AM
    From my experience, I would have to agree with Paul about the negative feedback. I had an amp made by TAD that you could adjust the feedback while listening. It didn't any time at all to hear a preference. No feedback, every time. Spec's certainly aren't everything, especially to the ear. That's where it becomes personal. If you like what you hear, after comparing different products, then that is what's right for you.
  And the Quickie is a good first step in hearing how these products sound. I have had the pleasure of upgrading a couple of BH components. By comparison, the Quickie gives outstanding result for the money. Hell, if a few upgrades are done, it shames many previous pieces of equipment that I have owned in the past. Again, it's about preferences.
  No doubt, you will hear many glowing references here about BH equipment, but in the end, you are the judge.



Offline Remoter

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Reply #4 on: April 26, 2013, 07:01:07 AM
Paul,
Am I understanding you to say that yes I will improve the sonic performance of the feedback heavy ST70 with the seduction/reduction pre and the absence of feedback in that pre, but that improvement may be limited by my amp's reliance on feedback?

And yes I understand that what were talking about is as subjective as it gets - if it sounds good to you blah blah blah. I am asking for your subjective biased opinion and it is greatly appreciated



Offline earwaxxer

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Reply #5 on: April 26, 2013, 08:22:52 AM
Hey Remoter, and welcome! - This might be a good opportunity for you to experiment with different 'sounds' to get a better feel for what a particular piece of kit may add, subtract etc. What many have found with the Quickie, myself included, is that amp 'A' can sound very different with/without the Quickie in the circuit. You may not want/need tubes downstream from the Quickie for example. I know for some thats blasphemy but its real. I think you will find that the Quickie sounds very good, and a simple T-amp for power amp is what the dr. ordered. - YMMV - Cheers - Eric

Eric
Emotiva XPA-2, Magnepan MMG (mod), Quickie (mod), JRiver, Wyrd4sound uLink, Schiit Gungnir, JPS Digital power cord, MIT power cord, JPS Labs ultraconductor wire throughout, HSU sub. powered by Crown.


Offline Zimmer64

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Reply #6 on: April 26, 2013, 08:47:40 AM
Hi Remoter,

For me the Quickie is a great piece of kit that added much to enjoyment of listening to music. Initailly I used a SS amp with it and was already thrilled. Now I am using it with a recent built of Bob Latino's VTA ST-70. Just awesome.
The Q is a great start into the BH world and it is easy to mod, PJCCS, cap upgardes etc. I still want to try a BH SET amp, but dont have speakers that are sensitive enough. Got to change those first.

Enjoy

Michael

Nelson Pass F5 Turbo V2, Quickie (mod), S.E.X. 2.1, Tubes4hifi SP14, Dynaco VTA ST 70, Tubelab SSE, Vroemen Diva Superiore ER4, Jordan JX92S VTL, 47 labs 0647 CD, Aqvox DAC, Rowen Absolute pre / psu / power amps, BG Neo3 / Betsy / Eminence A15 open baffles


Offline corndog71

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Reply #7 on: April 26, 2013, 11:49:33 AM
Congrats on jumping on a new Quickie! I think you will be very pleased with it.  And speaking from experience similar to Zimmer's, a rebuilt ST70 can be a fantastic way to get that full-on tube magic.  I rebuilt an ST70 using Joe Curcio's (Dynaco Doctor) upgraded driver and cap circuits.

I shot a couple of demo videos a few years ago so you can see and hear them in action!



I've since traded the ST70 away and built a brand new pair of Mark IV amps using Dynakitparts and Curcio upgrades.  They're fun amps.  If you haven't already done so I would highly recommend either Bob Latino's or Joe Curcio's upgrades to bring your ST70 into the 21st century.  The stock amps were designed to a price point with lots of compromises.  These upgrade circuits really squeeze the best out of these old amps.    I'm currently planning on building Bob Latino's ST-120 because I want to jump into the KT88 pool. 8)

I haven't tried the Bottlehead phono preamps but the Reduction is mighty tempting!  I currently use a Cambridge Audio 640P to good effect.

The world was made for those not cursed with self-awareness.

Rob


Offline pdxgrampa

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Reply #8 on: April 26, 2013, 12:56:12 PM
Hi Remoter,
I built one of Bob's ST-120s with KT-120 tubes,a Foreplay III,Zaph Audio Sr-71s,CSS sub and an OPPO Cd player for my daughter and son-in-law in who live in remote Wyoming a couple of years ago.It's a nice system.
I was speaking to her today while my 4 year old grandson was enjoying Joan Jett and the Blackharts with his lunch.   :)

Greg
Music Hall 5.1SE,EROS. OPPO 980HD, Music Hall 25.3 Dac. BeePre/BeeQuiet. Paramount V1.1 300B,Orca Deluxe W/ Subs/SPA250s.Stereomour W/Orca Deluxe. Crack W/Speeball(2) .Beyerdynamic 990s.Crackheadphone.


Offline Grainger49

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Reply #9 on: April 26, 2013, 01:40:03 PM
I used a ST-70 with my lower sensitivity speakers.  It sounded better than the Krell 250s.  If you need the power SET will not deliver that.  But once you have heard the sound of "one hand clapping," the sound of SET it will be next to impossible to go back. 

I had a rebuilt PAS-3 that I replaced with an ARC SP-14, which I replaced with the Bottlehead Foreplay 2. 

As Paul says, everybody hears things differently.  I guess that is why there is more than one maker of audio equipment.  Trust your ears.  You are the one to please.



4krow

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Reply #10 on: April 26, 2013, 02:30:57 PM
Yah, I do miss the sound of my old mono amps. Nothing is the same as SET



Offline Remoter

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Reply #11 on: April 27, 2013, 05:06:33 AM
Thanks for everyone's input - I don't know when the quickie will show but looking forward to getting started. I've been passivly looking for a phono preamp for a few months Yaqin and various cheap Chinese manufacturers, Dyna, BH and others. Thinking that I'll get the "all new, now even whiter" Reduction.
My ST70 is primarily stock but a complete tune up, some caps replaced, soft start added and blessed by Seattle (I live in the area) tube dude Roger Hugg.
Okay, so this is pretty cool - I have a plan!
Build, play with, tweak the Q.
Build, play with tweak the R.
ST70 mods. There seems to be a handful of companies/people that offer mods and they all seem to have their fans and detractors. I would love to hear some opinions but I suppose that is a different discussion.
Damn life is good!
Dan



Offline Grainger49

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Reply #12 on: April 27, 2013, 05:36:02 AM
Dan,

Check this on your ST-70:

Put one meter lead on the chassis, the other on the outer conductor of one of the RCA jacks.  If you measure about 10 ohms you will need to replace the 10 ohm resistors on the circuit boards with shorts.  This often causes hum because the signal isn't hard grounded.



Offline Remoter

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Reply #13 on: April 27, 2013, 06:23:07 AM
Okay, thanks Grainger.  I'll check it out.
Dan



Offline Paul Birkeland

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Reply #14 on: April 27, 2013, 06:38:06 AM
I can personally recommend a triode conversion, but at the same time I would say you must remove or greatly reduce the feedback loop.

If you find you have too much gain, you can triode strap the first half of the 7199 and rebias it to keep the phase inverter happy (your tube tech can help with this).

For upgrade boards, look for those who mention that they are lower gain, and perhaps that there are lower gain tubes that can be used. 

-PB

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man