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    Connecting a CD recorder to my SP/PH10

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    Dave_in_Va

    Posts : 142
    Join date : 2013-04-02

    Re: Connecting a CD recorder to my SP/PH10

    Post by Dave_in_Va on Sat Jan 30, 2016 5:05 pm

    I don't understand about the Audio Control's input impedance. I've been using it as an occasional EQ tweak and my system sounds great either with the Audio Control on or off.
    Thanks for the help.

    GP49

    Posts : 733
    Join date : 2009-04-30
    Location : East of the sun and west of the moon

    Re: Connecting a CD recorder to my SP/PH10

    Post by GP49 on Sat Jan 30, 2016 8:21 pm

    Dave_in_Va wrote:I don't understand about the Audio Control's input impedance. I've been using it as an occasional EQ tweak and my system sounds great either with the Audio Control on or off.

    That 100kΩ input impedance may not be critical depending on what equipment you are using upstream. With just about anything solid state it will be OK. If it's tube equipment feeding it, it will still be OK if the tube gear's output is a cathode follower or an impedance-isolating buffer. Even if it's a Dynaco PAS whose phono stage sees the Audio Control directly through a selector switch, it won't cause THAT much of a problem, only a bass roll-off that you may not notice with a lot of recordings.

    Where people run into problems is with input impedances of 10kΩ or so, when fed by tube equipment.

    tubes4hifi
    Admin

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    Re: Connecting a CD recorder to my SP/PH10

    Post by tubes4hifi on Sat Jan 30, 2016 8:59 pm

    that's a really nice tube amp buffer you linked to on ebay, but it's about double the price that it should be!!
    Here's one nearly identical for half the price . .. . http://www.ebay.com/itm/New-version-12AU7-tube-Class-A-tube-headphone-amplifier-preamplifier-w-psu/141093135880?
    Yes, the point that myself and Peter and GP49 have been making is that alot of SS gear has a very low input impedance (under 10K) whereas almost all tube gear has a very high input impedance (more than 200K) and that anything under 100K is going to load down your PAS preamp tape output and also mess up the phono RIAA EQ,
    so likely you will wind up needing a tube preamp/buffer staqe like the one you linked or the one I linked.
    If you don't need a chassis I've got a new unstuffed AIKIDO buffer board for $30 that would need about $30 worth of parts to stuff, plus a $35 power transformer,
    but your ebay link and mine are both ready to use as is so more convenient.

    Dave_in_Va

    Posts : 142
    Join date : 2013-04-02

    Re: Connecting a CD recorder to my SP/PH10

    Post by Dave_in_Va on Sat Jan 30, 2016 9:09 pm

    I appreciate the help. I'm not too sure exactly what the PAS is (an older Dynaco preamp?). I have a SP10 with the PH10 built in. VTA 70 power amp.
    Just trying to be clear.

    (Do you think there is any chance that running out of the EQ tape out instead of the SP/PH10 will make a difference?)

    GP49

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    Re: Connecting a CD recorder to my SP/PH10

    Post by GP49 on Sat Jan 30, 2016 9:14 pm

    Dave_in_Va wrote:I appreciate the help. I'm not too sure exactly what the PAS is (an older Dynaco preamp?). I have a SP10...

    The PAS is the old Dynaco stereo tube preamp.

    For your SP10, either Ray or Bob will be able to advise (if either of you is reading, chime in!).  It depends on where you are connecting your Audio Control (which circuit is feeding it) and how tolerant is is of a 100KΩ input impedance.

    Dave_in_Va

    Posts : 142
    Join date : 2013-04-02

    Re: Connecting a CD recorder to my SP/PH10

    Post by Dave_in_Va on Sat Jan 30, 2016 9:27 pm

    The main out of the SP10 which normally goes to the VTA ST70 goes to the Audio Control EQ input, that output goes to the ST70.
    Nothing currently is coming/going to any tape ins/outs.
    (The CD burner arrives Tuesday.)

    peterh

    Posts : 679
    Join date : 2012-12-25
    Location : gothenburg, sweden

    Re: Connecting a CD recorder to my SP/PH10

    Post by peterh on Sun Jan 31, 2016 4:54 am

    Dave_in_Va wrote:The main out of the SP10 which normally goes to the VTA ST70 goes to the Audio Control EQ input, that output goes to the ST70.
    Nothing currently is coming/going to any tape ins/outs.
    (The CD burner arrives Tuesday.)
    Ahh, thats another way. Then it won't load the riaa. ( but it will be affected by the volume control)
    Yes, you could connect the out to the cd-burner. No problem.

    The "classical way" of introducing a EQ is to feed the eq from "tape out" and channel the
    EQ output to "tape in" ,ans using the "after tape" switch on the amp. Commonly called "tape loop".
    Connected this way the signal is tapped before any volume/tonecontrols. I do not know
    if your SP10 is equipped with a "after tape" switch.

    But by all means test. You won't damage anything.

    Dave_in_Va

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    Join date : 2013-04-02

    Re: Connecting a CD recorder to my SP/PH10

    Post by Dave_in_Va on Sun Jan 31, 2016 11:22 am

    Thanks Peter.
    Yes, I have the in/out loop and in fact the Audio Control manual recommends hooking it up this way.
    I'm going to leave it as it is, as it seems to work fine on the rare occasions I use it.

    The CD burner will be here in two days and I'll try it connected to the "tape out" of the Audio Control. It'll be great if it works. If not I'll be picking out a tube buffer.

    For what it's worth, the main reason I decided to go with a burner is that recently I've been buying and really enjoying a load of LPs by Popul Vuh. By the time I pay the shipping these things cost about $40 a pop. I want to have some available for a 1600 mile drive coming up this April and simply don't want to start duplicating them with $15.00 CD's.

    (Also, as far as I can tell, my SP10 is just an SP9 with no tone controls, and yes, it has the "Source/Tape" switch.)

    tubes4hifi
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    Re: Connecting a CD recorder to my SP/PH10

    Post by tubes4hifi on Sun Jan 31, 2016 2:18 pm

    going back to the beginning of the thread, Troy's suggestion on using the $35 amp/buffer from MCM is probably your best way to go for no fuss.
    Connect it to the TAPE OUT on your SP10. Then to the EQ. Then the EQ out to the recorder and/or amplifier.

    peterh

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    Join date : 2012-12-25
    Location : gothenburg, sweden

    Re: Connecting a CD recorder to my SP/PH10

    Post by peterh on Sun Jan 31, 2016 2:57 pm

    The MCM amp has to low input impedance ( 47k)

    Here is one that should have > 500k ( at least if it follows the x-10D schematic) This is a ready-built
    device with builtin powersupply, just connect the rca cables and off you go :
    http://www.ebay.com/itm/Finished-Tube-6N11-X-10D-Buffer-Pre-AMP-preamplifier-Base-on-Musical-Fidelity-/141093091305?hash=item20d9cdb7e9:g:-mQAAOxyg7xSYAQs

    An suggestion : as this is not the first time a simple buffer is needed, why don't
    Roy make one, boxed with PSU ? And also sell the cathode-follower board as a kit ?


    Last edited by peterh on Sun Jan 31, 2016 3:00 pm; edited 1 time in total (Reason for editing : kit suggestion)

    Dave_in_Va

    Posts : 142
    Join date : 2013-04-02

    Re: Connecting a CD recorder to my SP/PH10

    Post by Dave_in_Va on Sun Jan 31, 2016 3:26 pm

    How's this one look? I didn't see the impedance but it appears to be hand wired (and ships from Canada).
    I'm not familiar with these tubes (6J1).

    http://www.ebay.com/itm/YAQIN-SD-CD2-Stereo-Audio-Processor-Tube-Buffer-/141890400874?hash=item210953b26a:g:uA8AAOSwrklVc26d

    Looks like I'm getting two different opinions. I'm hoping the recorder will work coming out of the EQ's "tape out" as discussed earlier.

    Thanks again for all of the help.

    (And Roy, as long as you're here, does my SP10/PH10 use a 12X4 or 6X 4 rectifier? Thanks.)

    peterh

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    Re: Connecting a CD recorder to my SP/PH10

    Post by peterh on Sun Jan 31, 2016 3:35 pm

    Dave_in_Va wrote:How's this one look? I didn't see the impedance but it appears to be hand wired (and ships from Canada).
    I'm not familiar with these tubes (6J1).

    http://www.ebay.com/itm/YAQIN-SD-CD2-Stereo-Audio-Processor-Tube-Buffer-/141890400874?hash=item210953b26a:g:uA8AAOSwrklVc26d

    Looks like I'm getting two different opinions. I'm hoping the recorder will work coming out of the EQ's "tape out" as discussed earlier.

    Thanks again for all of the help.

    (And Roy, as long as you're here, does my SP10/PH10 use a 12X4 or 6X 4 rectifier? Thanks.)

    This amp is spot on ! ( it mentions cathode follower, and as suck it use to have high input
    impedance. If not there is nothing a solder cannot fix ). Go for it !

    Dave_in_Va

    Posts : 142
    Join date : 2013-04-02

    Re: Connecting a CD recorder to my SP/PH10

    Post by Dave_in_Va on Tue Feb 02, 2016 8:39 pm

    Well, I tried it directly out of the "tape out" of the SP10/Ph10 and also out of the "tape out" of the Audio Control.

    Both worked. Probably better directly out of the preamp but it's kind of a moot point. I got a decent CD recorded but it definitely loaded the system down. I unplugged the connects from the "tape out" as it was playing and the audio quality increased greatly. It was very noticeable.

    So I guess the buffer between the SP10/PH10 and the Tascam burner is the answer.

    Do you guys all think this one is the ticket? I don't see any listing for the input/output impedance.

    http://www.ebay.com/itm/131717897994?_trksid=p2055119.m1438.l2661&ssPageName=STRK%3AMEBIDX%3AIT

    (It looks cool, it's tube, it's point to point hand wired, the tubes seems to be readily available as cheap NOS, and it ships from Canada.)

    Thanks again for all of the help.
    Come hell or high water I'm going to be listening to my expensive Krautrock psych LP collection on the Pa./Ohio/Indiana Turnpike this Spring!

    peterh

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    Location : gothenburg, sweden

    Re: Connecting a CD recorder to my SP/PH10

    Post by peterh on Wed Feb 03, 2016 1:26 am

    Yes, it's your choice.
    A guy in audiokarma made a schematic :
    http://audiokarma.org/forums/index.php?attachments/cd2-schematics-jpg.367394/

    It has input impedance in the meg region.

    Dave_in_Va

    Posts : 142
    Join date : 2013-04-02

    Re: Connecting a CD recorder to my SP/PH10

    Post by Dave_in_Va on Wed Feb 03, 2016 9:43 am

    It appears to be a little nicer than this one...

    http://www.ebay.com/itm/290827407364?_trksid=p2055119.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT

    peterh

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    Location : gothenburg, sweden

    Re: Connecting a CD recorder to my SP/PH10

    Post by peterh on Wed Feb 03, 2016 12:17 pm

    Dave_in_Va wrote:It appears to be a little nicer than this one...

    http://www.ebay.com/itm/290827407364?_trksid=p2055119.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT

    Aggree!

    Dave_in_Va

    Posts : 142
    Join date : 2013-04-02

    Re: Connecting a CD recorder to my SP/PH10

    Post by Dave_in_Va on Wed Feb 03, 2016 12:21 pm

    Ordered. I'll let you know how this finally shakes out.
    Thanks again.

    GP49

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    Re: Connecting a CD recorder to my SP/PH10

    Post by GP49 on Wed Feb 03, 2016 12:32 pm

    Dave_in_Va wrote:It appears to be a little nicer than this one...

    http://www.ebay.com/itm/290827407364?_trksid=p2055119.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT

    I like the regulated B+ and cathode supply of the EBay one.

    Dave_in_Va

    Posts : 142
    Join date : 2013-04-02

    Re: Connecting a CD recorder to my SP/PH10

    Post by Dave_in_Va on Wed Feb 03, 2016 1:45 pm

    Which eBay one? They were both on eBay.

    I bought this one...

    http://www.ebay.com/itm/131717897994?_trksid=p2055119.m1438.l2661&ssPageName=STRK%3AMEBIDX%3AIT

    GP49

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    Re: Connecting a CD recorder to my SP/PH10

    Post by GP49 on Wed Feb 03, 2016 3:40 pm

    Dave_in_Va wrote:Which eBay one? They were both on eBay.

    I bought this one...

    http://www.ebay.com/itm/131717897994?_trksid=p2055119.m1438.l2661&ssPageName=STRK%3AMEBIDX%3AIT


    The MK4 Indeed has the regulated power supply, but probably less storage capacitance. The regulation is solid state,
    so if you are into all-tubes, it's not for you.

    I put no preference into hand-wired vs. PCB construction.


    Dave_in_Va

    Posts : 142
    Join date : 2013-04-02

    Re: Connecting a CD recorder to my SP/PH10

    Post by Dave_in_Va on Tue Feb 09, 2016 10:55 am

    I received the Yaqin buffer yesterday. It seems like a really nice unit. Heavy, seems well built and has a nice heavy duty power cord. The Yaqin logo lights up nicely. I did replace the tubes with some NOS GE 5654W. They appear to be cheap and plentiful ($12.50 shipped for the pair).

    I hooked it up as per Roy's suggestion with the buffer and the Audio Control EQ in the pre-amps "tape out/tape in" loop. I used the Audio Control's "tape out" to go to the Tascam CD recorder.

    Works perfectly and I don't hear any change going from "source" to "tape".

    Per Bob's earlier thread, I ordered several interconnects from SignalCable and then I'm done.

    It's all good. I appreciate all of the suggestions.

    (The one CD I recorded came out great.)

    peterh

    Posts : 679
    Join date : 2012-12-25
    Location : gothenburg, sweden

    Re: Connecting a CD recorder to my SP/PH10

    Post by peterh on Tue Feb 09, 2016 11:00 am

    Nice to hear that it fulfilled your expectations.

    Why don't we see such buffers from roy ? Both boards that could be mounted internally into
    some device and the same boards mounted in a box with power supply. One 12au7 is all that
    is needed for stereo, 20mA of B+ and 300mA of 6.3V AC

    GreggW

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    Join date : 2015-07-15

    PAS 3 tape loop impedance

    Post by GreggW on Tue Feb 09, 2016 4:59 pm

    I'm close to buying a Tascam CD burner and wonder if It will work on the tape loop with my PAS 3. It has a Tube Nirvana TCLA board in it.

    deepee99

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    Location : Wallace, Idaho

    Re: Connecting a CD recorder to my SP/PH10

    Post by deepee99 on Wed Feb 10, 2016 2:55 pm

    You might also want to look into a used HHB CDR-850 off the 'Bay. It's a think a Pioneer offshoot, Japanese built, and uses Pioneer's proprietary 5-clamp CD turntable so that the disk isn't just wobbling around on a spindle. It's got all the bells and whistles, XLR, digital and analogue ins and outs etc., etc. They were very expensive to make so price-wise didn't catch on well. I picked up a store demo for $250 and it arrived looking and sounding brand-new. Haven't delved into the vinyl-recording part yet but the playback is superb. The only funky thing about the transport is that you load the disc upside-down because it sits on a full turntable. It's a very heavy machine and the drawer glides in and out like it was lubed with gun-oil. It will record to both CD-R and CD-RW formats.Guess I can throw that green marker pen away now Laughing


    audiobill

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    Location : Philadelphia

    Re: Connecting a CD recorder to my SP/PH10

    Post by audiobill on Thu Feb 11, 2016 7:54 am

    Why burn CDs vs just streaming Tidal?

    I haven't touched a CD in years.

    iphone and Android apps available......

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