Paradigm Studio Monitors - Tweeter Replacement

After years of admirable service (manufactured early 90s, bought ~2010), the left tweeter did not produce sound anymore. Thankfully, the rest of the drivers were fine. Crossover seemed ok also - tested via swapping the tweeter with the right speaker.

These usually played audio from a Logitech Squeezebox (a surprisingly vibrant open-source community now) or Pioneer Elite DV-59AVi, both to a Sony STR-DA7100ES (i-link firewire with H.A.T.S, PQLS). No bi- or tri-amping.

Access to the tweeter is through the front, behind the dust screen. The rear does not seem user serviceable.

A multimeter test showed intermittent open circuit or ~ 100s of Ohms. Nominally 6 Ohms.

Original markings were: D26TG-56, 6 Ohms, 902 . Some digging revealed these as Vifa 1-inch silk dome tweeters.

I was going to call Paradigm. At this time, e-mail is the only option. Their response took about a week. They have these tweeters. They were $175 a piece, plus shipping; crossovers were $125 plus shipping.

I elected to use these: Peerless D27TG35-06 . Seemed to be a good fit visually. There were a few options for replacement silk/fabric dome diaphrams, but their value was not compelling.

 

 

In the pictures below, the left is the original; the right is the replacement. Though they looked very close, there was a slight out of round difference between the original and new frame. I swapped the frames, and installation went ok.  Though the mounting screws had different heads, the length and the type of screws were compatible.
The height difference did not seem to make a difference in this application.

 

 

The innards look similar also. 

 

People usually scoff at break-in for electronics. But in this case, it made a difference in my setup, to my ears. After installation, the new tweeter sounded like it had low gain, compared to the stock one. After a couple of days, it recovered gain and sounded much better - almost on par with the original. I still think the original sounds a tad better, but I am happy with the value proposition. 

References:

1. Stereophile review 1992. Lists a metal dome tweeter. My example had a silk dome tweeter.
2. Not very helpful literature from Paradigm

 

Burson V5i in Sony DVP-S7000

As readers of this blog may know, my reference CD player is a DIY modified Rotel RCD-855. 

I also have a Sony DVP-S7000 and it is revered for its transport. People also consider upgrading output opamps a big step up. 

Burson kindly sent me V5i Dual op-amp samples and its compact size seemed like a good fit in this application.

I measured the input voltages for IC202 and IC302. They were non-symmetric. About -7V and 5V , comfortably within the V5i spec of +/-15V . I did not change  LPFs IC201 and IC301. I had to tweak the legs a little to make the V5i stay and have good contact, since the board would be mounted upside down. Perhaps the trouble was with the opamp sockets.

I also swapped out the 100uf, 25V coupling capacitors with Blackgates from a donor. 

From previous comparisons, this Sony was different and quite far away from my Rotel reference. I spun up some CDs and compared them now. I realize this is not ideal: only changing one component, keeping everything else the same. But it was what was possible in this case.

At first, bass sounded boomy on the Sony. Per Burson's recommendation, I let it run for ~ 100 hours. It sounded better after that. 

During the comparison:

  (1) Bass sounded impressive on the Sony. Details were different with the Rotel. 

  (2) L and R channels seemed more coherent on the Sony. Choruses and ambience were better on the Rotel. High frequencies were exquisite on both.

  (3) Instruments individually sounded better on the Sony. Vocals were a tad recessed on the Sony. The whole sounded slightly better on the Rotel

The reference Rotel still stays ahead by a hair. But the Sony has improved by leaps and bounds.

Songs:

(1) Fragile
(2) Why Should I Cry For You
Fields of Gold: The Best of Sting 1984-1994
Sting

(3) Fill Her Up
Brand New Day
Sting

(4) The Hat
(5) The Way I Am
Girls and Boys
Ingrid Michaelson

Associated equipment:

Iron SE DIY preamp  Zen Mod Labs

Babelfish ᄅſ DIY power amplifier  Zen Mod Labs

Pioneer SP-FS51-LR speakers

 

References: 

http://www.agoraquest.com/forums/viewtopic.php?t=32249

Build quality is excellent. I am surprised by the number of ICs

 

Original OpAmps

 

Caps swapped and sockets installed

 

V5i-D installed

Klipsch Promedia 2.1: fixing a broken channel

After years of living with only a single channel, I attempted a repair and it has been successful so far. Though there is a turn on thump (perhaps because the output devices are not as matched), it seems to work ok. 

In one HF channel, the fuse had blown and kept blowing. This was the initial symptom. I suspect the culprit was the original goop used to hold things together. It became conducting and shorted out one output device (TIP41C). The blackening of the board is suggestive of this.

Thanks to the excellent work by the folk listed in the references below, I had an idea of what to do. In the end, I replaced both Q9, Q10 (TIP41C and TIP42C respectively), and Q6 2N3904. TIP41C had all terminals shorted; TIP42C measured ok. I also changed out a couple of resistors that seemed very charred, though they measured ok (They fell apart when removed from the board). There were mica insulators between the output devices and the heatsink. I cleaned the old heatsink compound and applied new compound. The main clue was to compare measurements between the working and non-working channels.

There is an initial offset of about 60mV in the channel I repaired. This is about 20mV in the other channel. They both settle to about 5mV higher in a few minutes. There was some discoloration in the LF amp board but I did not change anything since it works.

References:

http://christopherbradshaw.net/The_Project_Bin/klipsch%20promedia%20subwoofer%20repair%20-%20page%201.html

http://www.thompdale.com/bash_amplifier/2-1/2-1_bash_amp.htm

http://diyaudioprojects.com/Forum/viewtopic.php?t=4892

Review of Burson Audio Classic V6 op amp in a DIY WHAMMY headphone amplfier

 Thanks to Burson for providing V6 Classic Duals.

Summary? I like V6 Classic over V6 Vivid, in this application.

I changed my testing slightly from my earlier review of V6 Vivid. A couple of different songs. Source volume from the phone is full.

These stayed the same:
Input: Samsung Galaxy S9 plus
Headphones: Sony MDR-7506
No changes to WHAMMY (18V transformer, naked 15V regulators)

The goal is to pick between V6 Classic and the earlier samples of V6 Vivid. Again, I listened to both the op-amps back to back. No instrumentation.

Songs:
(1) Track 1 Unaccompanied Cello Suite No. 1 in G Major, BWV 1007: I. Prélude from Six Evolutions - Bach: Cello Suites, Yo-Yo Ma (2018)
(2) Track 4 The Four Seasons, Violin Concerto in F Minor, Op. 8 No. 4, RV 297 "Winter": II. Largo from Appassionato, Yo-Yo Ma (2007)
(3) and (4) Fragile and Be Still My Beating Heart, Tracks 9 and 6 from Fields of Gold: The Best of Sting 1984–1994 (1993-1994)
(5) Sugar, Track 6 from Free Life, Dan Wilson (2007)
(6) Lies, Track 6 from After Forever, Kasper Bjørke (2014)
(7) You're Getting to Be a Habit with Me, Track 8 from Love Scenes, Diana Krall (1997)
(8) and (9) Breakable and The Way I Am, Tracks 3 and 5 from Girls and Boys, Ingrid Michaelson (2006)

Vivid:
Fragile: Somewhat fatiguing
Be Still My Beating Heart: The supporting chorus was clear
Sugar: Midrange was better than high frequencies (which sounded a little recessed)
Good supporting vocals

Classic:
Fragile: Chorus sounded good
Be Still My Beating Heart: The Guitar sounded nicer than the chorus. Delicate high hats
Sugar: Even better Midrange instruments. Voices had more emotion.
Lies: More complex presentation of instruments
Breakable: The hand drum in the left channel was fantastic. Beautiful lower bass.

Vivid made instrument separation good. Classic let me distinguish between the different notes made by those instruments.
With the Classic, I started to enjoy the music.

I'll keep the Classic in my Whammy. 

 

 

Review of Burson Audio Vivid V6 op amp in a DIY WHAMMY headphone amplfier

 

Thanks to Burson Audio for the samples of Supreme Sound OpAmp Vivid V6.

Marking on the box: V6V-D-2

It came thoughtfully packaged with 2 DIP-8 adapters. I had already installed such an adaptor in my Whammy.

My build was with the PCBA from https://diyaudiostore.com/. I sourced parts myself and stumbled many times with lots of rework.

Supply: +/- 15 V straight regulators. no LED or voltage divider

Input:  Samsung Galaxy S9 plus. Volume two notches below maximum

Headphones: Sony MDR-7506

Gain with the Vivid V6 seems to be higher than with the baseline OPA2134PA. Gain matching was by ear. I realize this is not as accurate as with instrumentation. This was not a blind test. I heard the songs below with the OPA2134PA and then swapped it out for the Vivid V6, leaving everything else the same.

I had to move surrounding components a little. The footprint of the Vivid V6 is a little larger. Luckily, the box I used is big enough for height. so I'll let it stay a while.

(1) Track 1 Unaccompanied Cello Suite No. 1 in G Major, BWV 1007: I. Prélude

from Six Evolutions - Bach: Cello Suites, Yo-Yo Ma (2018)
(2) Track 4 The Four Seasons, Violin Concerto in F Minor, Op. 8 No. 4, RV 297 "Winter": II. Largo from Appassionato, Yo-Yo Ma (2007)

(3) and (4) The Hat and The Way I Am, Tracks 4 and 5 from Girls and Boys, Ingrid Michaelson (2006)

(5) Track 2 Künstliche Welten (Praha-Edit) from Künstliche Welten, Wolfsheim (2004)

(6) Track 10 How Deep Is the Ocean (How High Is the Sky) from Love Scenes, Diana Krall (1997)

The sound: there is more detail and more bass. Notes, and instruments are separately identifiable.

After this I continued to listen to many songs with the Vivid V6. In familiar songs, I was surprised, especially at the start and end of songs: sometimes I could discern extra vocals, instruments or notes.

That said, I think I am spoiled by ZenMod's Iron Pre. With that, I enjoy the music without paying attention to accuracy or anything else. With the Vivid V6, with my setup, to my ears, there seems to be something amiss. I don't know how else to say it.

In the words of our resident wise man "this is Entertainment - not Dialysis". It is good to have choices and even better to listen to a few.

Links:

https://www.bursonaudio.com/products/supreme-sound-opamp-v6/

https://www.ti.com/store/ti/en/p/product/?p=OPA2134PA

https://pro.sony/ue_US/products/headphones/mdr-7506

https://guides.diyaudio.com/Guide/WHAMMY+headphone+amplifier/3

"this is Entertainment - not Dialysis" from http://www.firstwatt.com/pdf/art_h2_v1.pdf

DVDA

I tried a few methods, but none made a functioning DVDA (in Pioneer Elite DVD-59AVi) until this
http://rdhsoftware.blogspot.com/p/dvda-gui.html

It is a front end for a few other open source software.

It seems to have trouble with files of different sample rates. But not those sample rates itself. For example, mixing an 88Khz and a 96Khz file - no go. But each works separately.

Reset Pioneer DVD players without a display or remote

1) Switch the player into standby and empty the disc tray.
2) Using the front panel buttons, hold down the STOP button and press STANDBY/ON to switch the player back on.

From

http://www.pioneerfaq.info/english/dv400.php?player=DV-400V&question=Extras