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Glassware Phono pre Project (Read 633 times)
4krow
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Glassware Phono pre Project
09/01/21 at 11:52:45
 
Some time ago, I started the phono pre project which was designed by Pete Millett. It was an LR design, and I was curious as to what it might sound like. Unfortunately, the key inductors were not available for months, so the decision was made to start a mew phono pre project by John Broskie. It is much more expensive and uses 2 power transformers, 8 EC81 tubes, and takes up a lot of space, requiring a full sized chassis. Here is what I have so far. The boards are very sturdy and thick. The parts are not skimped anywhere. In a couple of weeks I will have the chassis drilled and ready to go.https://ibb.co/GQ6sC1j
https://ibb.co/hMbxB6v
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Decware 34I.3 integrated amp/Forte' 3 bass amp/Velodyne SMS-1 bass mngmnt system/Decware ZOB speakers/Audio Nirvana 8" bass drivers/Xiang Seng DAC/ LR Audio Computer/Rega Apollo R CDP/Emotiva ERC3 CDP/BPT 3.0 power cond.
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EdwardT
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Re: Glassware Phono pre Project
Reply #1 - 09/01/21 at 12:44:29
 
Is that massive power supply FET regulated?
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Amp on order, Gr-Research X-SLS, Marantz HD CD-1
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4krow
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Re: Glassware Phono pre Project
Reply #2 - 09/17/21 at 02:49:08
 
What I do know is that the power supply uses 4 LD1085 voltage regulators (I think FET?), and an IXCP 10M45S High voltage constant current source. The 8 tube filaments use a bunch of current (240ma), whereas the high voltage supply (240 VDC) only needs about 45-50 ma.
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Decware 34I.3 integrated amp/Forte' 3 bass amp/Velodyne SMS-1 bass mngmnt system/Decware ZOB speakers/Audio Nirvana 8" bass drivers/Xiang Seng DAC/ LR Audio Computer/Rega Apollo R CDP/Emotiva ERC3 CDP/BPT 3.0 power cond.
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Dana
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Re: Glassware Phono pre Project
Reply #3 - 09/17/21 at 16:24:17
 
That's beautiful.  How does it sound?
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Tom Waits:
And the newspapers were fooling,
And the ash-trays have retired
'Cause the piano has been drinking,
The piano has been drinking
The piano has been drinking,
Not me, not me, not me, not me, not me
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4krow
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Re: Glassware Phono pre Project
Reply #4 - 09/17/21 at 20:36:32
 
 Thanks. Dude, I am gritting my teeth awaiting the last parts to arrive today! Got just a bit more drilling to do on the rear panel and then the final AC work can begin. The power supply is fine and the tubes light up, so there is that. I just want to get all the ducks in a row before takeoff.

 FWIW, Mr. Broskie's designs are simply great. Only point to point wiring and a tube based rectifier would help.
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Decware 34I.3 integrated amp/Forte' 3 bass amp/Velodyne SMS-1 bass mngmnt system/Decware ZOB speakers/Audio Nirvana 8" bass drivers/Xiang Seng DAC/ LR Audio Computer/Rega Apollo R CDP/Emotiva ERC3 CDP/BPT 3.0 power cond.
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Stefan
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Re: Glassware Phono pre Project
Reply #5 - 09/18/21 at 05:24:06
 
Looks great! Looking to upgrade my phono preamp soon as well, this looks interesting… how much are the parts roughly?
And looking forward to hear how it sounds!
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- Stefan
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Rega rp6, Lounge Audio phono pre-amp, Lonely Raven PC, T+A DAC 8 DSD, ZBIT, ZROCK2+25th, SE84UFO25, Torii IV, Denon AVC-1SE, Infinity IRS Beta, Tannoy Cheviot, ERRx, Tiny Radials, Woo WA-3, Sennheiser HD800S
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EdwardT
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Re: Glassware Phono pre Project
Reply #6 - 09/18/21 at 16:43:19
 
Very nice, those LD1085s have a reputation of being very consistent and that’s exactly what you want for a phono preamp.
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Amp on order, Gr-Research X-SLS, Marantz HD CD-1
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4krow
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Re: Glassware Phono pre Project
Reply #7 - 09/18/21 at 21:04:05
 
Stephan, I may finish today. Always waiting for epoxy to cure or glue to dry, or paint to look good. I will assemble in a minute or two and then send along photos.
 FWIW, look to spend about 1k$ for a project like this. I didn't want to go that deep, but my previous phono project just couldn't happen when the parts got scarce. It was kind of a cruel joke that those parts arrived two days after I ordered this kit! Ended up trading the first phono project to a friend, and built this one.
 Ed, Yes Mr. Broskie has it together all the way with his products. My only concern is when I don't fully understand which part to choose when it comes to custom application.
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Decware 34I.3 integrated amp/Forte' 3 bass amp/Velodyne SMS-1 bass mngmnt system/Decware ZOB speakers/Audio Nirvana 8" bass drivers/Xiang Seng DAC/ LR Audio Computer/Rega Apollo R CDP/Emotiva ERC3 CDP/BPT 3.0 power cond.
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4krow
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Re: Glassware Phono pre Project
Reply #8 - 09/18/21 at 21:36:19
 
Ok so, here is the idea of this build. Why are the inputs on the side? Because it creates a much shorter path away from other electronics. Why are there two ground posts? Because I don't know yet. I will find out when the build is being tested. What would I do different? Damned good question. TBD after use.
https://ibb.co/DtM5QKb
https://ibb.co/gvcTsv1
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Decware 34I.3 integrated amp/Forte' 3 bass amp/Velodyne SMS-1 bass mngmnt system/Decware ZOB speakers/Audio Nirvana 8" bass drivers/Xiang Seng DAC/ LR Audio Computer/Rega Apollo R CDP/Emotiva ERC3 CDP/BPT 3.0 power cond.
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Stefan
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Re: Glassware Phono pre Project
Reply #9 - 09/19/21 at 22:56:56
 
Thanks for the infos 4krow! Looks very professional. I hope it sounds as good too Smiley
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- Stefan
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Rega rp6, Lounge Audio phono pre-amp, Lonely Raven PC, T+A DAC 8 DSD, ZBIT, ZROCK2+25th, SE84UFO25, Torii IV, Denon AVC-1SE, Infinity IRS Beta, Tannoy Cheviot, ERRx, Tiny Radials, Woo WA-3, Sennheiser HD800S
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4krow
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Re: Glassware Phono pre Project
Reply #10 - 09/19/21 at 23:18:08
 
Stephan thanks, it was more work than I normally put into a unit. AND well, one channel sounds good, but there is a bad hum in the other. Yup, something that I did somewhere concerning a grounding issue. That is one thing that I appreciate about stereo, and that is you may have a reference if the trouble is only in one channel.
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Decware 34I.3 integrated amp/Forte' 3 bass amp/Velodyne SMS-1 bass mngmnt system/Decware ZOB speakers/Audio Nirvana 8" bass drivers/Xiang Seng DAC/ LR Audio Computer/Rega Apollo R CDP/Emotiva ERC3 CDP/BPT 3.0 power cond.
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4krow
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Re: Glassware Phono pre Project
Reply #11 - 11/10/21 at 19:53:46
 
I'll be short and say that this pre went to a really good tech for repair probably due to a mistake that I could not find. So far, neither can he. crap. In the meantime, I was successful at building a phono preamp designed by Pete Millett. It also had issues at first but they have been straightened out. FWIW, the sound is quite superior to the Vincent PHO8 that I was using before. Man, this TT stuff has taken forever to get right. I am still convinced that the cartridge or maybe connection of tonearm cable is not optimal. Who knows, someday I will have the TT sounding as it should. I am about 70% of the way there so far.
 Got a shot of the PM phono board here:

https://ibb.co/rQDKW2N
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Decware 34I.3 integrated amp/Forte' 3 bass amp/Velodyne SMS-1 bass mngmnt system/Decware ZOB speakers/Audio Nirvana 8" bass drivers/Xiang Seng DAC/ LR Audio Computer/Rega Apollo R CDP/Emotiva ERC3 CDP/BPT 3.0 power cond.
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Stefan
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Re: Glassware Phono pre Project
Reply #12 - 11/14/21 at 04:57:44
 
DIY is fun, but always full of pitfalls, very rarely my projects work out perfectly in the first try...
Hope you will get all the issues strengthen out and get your sound from 70% there to 110%  ;)
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- Stefan
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Rega rp6, Lounge Audio phono pre-amp, Lonely Raven PC, T+A DAC 8 DSD, ZBIT, ZROCK2+25th, SE84UFO25, Torii IV, Denon AVC-1SE, Infinity IRS Beta, Tannoy Cheviot, ERRx, Tiny Radials, Woo WA-3, Sennheiser HD800S
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