Prem5 Refresh Update

[Pynchon]

Hello CJO community,

It has been about 5 months since I completed my refresh project (https://www.conradjohnsonowners.com/vie ... php?t=2497), thought I might post an update.

The Prem5s have been used EXTENSIVELY since completing the refurb. Operation has been largely trouble free (knock on wood) though I did have one tube go out. Startling to hear it to say the least. I was close and was able to turn the amp off almost immediately. Thankfully, the BBS-3 did it's job. Ordered several more BBS-3s from Mouser at full price rather than risk something cheap from Amazon.

The amps, with all the new capacitors, have really settled in and sound fantastic to my ears. Ironically enough, I have been mostly using the Spatial Audio open baffle speakers (95 or 96dB @ 4 ohm) which are even more efficient than the Focal 1038BEs. Given the acoustic challenges in the room, the open baffle speakers project far better in the space. The open baffle sounds so good, I have been searching for a pair of Spatial Audio Lumina L2s. Apparently, they are rather rare as I have not found single pair posted for sale within the last 2 or 3 years...

The Prem5s have been mostly used the upgraded ModWright SWL 9.0 Linestage (Dan installed a new tube rectified power supply and cap upgrade 2 years ago). However, I recently had an incident in which the preamp kept blowing its fuse. After Dan Wright tried to talk me through some basic trouble shooting, I ended up sending it back to him. It turned out to be a fluke incident with a short on the PCB. According to Dan, this had happened to a couple of the units over the years. ModWright fixed the issue without charge, burn tested it and sent it back within 5 days (back before Christmas). Thanks Dan and the ModWirght team.

In the interim, I used my father's Luxman CL-34 tube preamp with the Prem5s. The CL-34 sounded fantastic but, now that I have the SWL 9.0 Linestage back, the ModWright unit sounds better. Perhaps I will refresh the CL-34 given it is about the same age as the Prem5s.

Now that the Prem5s have proven to be stable, I finally took the plunge and ordered new output tubes. The previous owner had Svetlana EL34s for the Prem5s. After a bit of research and given the implied expense of tube rolling the Prem5s, I played it safe and ordered 17 new Mullard EL34s from Upscale Audio. Can't wait to hear them. I gather from this forum and others that these tubes take about 100 hours to break in.

Stay tuned and Happy New Year!

[Pynchon]

Forgot to mention that I finally replaced the old Auralic Aries streamer (way too buggy) with a Lumin U2. Quite happy with it this far.

[admin]

Glad it worked out. That "refresh" you did on the Premier 5 is really unprecedented. Really great job and I'm glad to hear you are enjoying the fruits of your labor.

I would love to hear your comparison of the Auralic vs Lumin streamers.

[AnotherJohnson]

That’s great! Congratulations!

[Big Dog RJ]

Good stuff matey!

I can certainly confirm that the Mullards are really tops! Very musical indeed and will be a fine match in the Prem5's.
The last time I heard the EL34 Mullard combination was with an ARTsa amplifier, driving the AG Duo XD horns, it was mighty fine!

A very happy New Year to you and all, and best of the best!
A big WOOF to 2023!
RJ

[AnotherJohnson]

A very happy New Year to you and all, and best of the best!
A big WOOF to 2023!
RJ

Yes! You’ve got the jump on us. We’re still counting it down.

We did see some news coverage suggesting that your ABC’s coverage was a bit off center for some Aussie viewers, but we will probably see the same here tonight.

My mother used to say that you can’t please everyone, so you might as well please those that agree with you.

[Pynchon]

Happy New Year! Hope everyone enjoyed the holidays.

As for Auralic vs. Lumin, it is not a fair comparison given the multi-generational difference. The Auralic was their 1st gen release while the Lumin was just released. Ultimately, it was the 1st gen Auralic's unstable & chronic SW bugs that became intolerable.

Not surprisingly, the Lumin (with MQA decoding, etc.) has forced a serious look at my DAC. My Metrum Menuet chipsets have two chipset upgrade options but no MQA module option. Metrum Pavane might be the way to go.

The Mullard EL34 are still within their 100 hour break-in period. My initial impression was disappointing but they are really coming into their own. Very happy.

As the Mullard have settled, I have become increasingly appreciative for their higher volume performance. Perhaps the Svetlana tubes are more tired than my tube tester suggested.

Once the Mullards are fully settled, I will do additional comparisons between the Mullards and Svetlanas using both the Focals and Spatial Audio speakers.

All the best!

[admin]

Happy New Year! Hope everyone enjoyed the holidays.

As for Auralic vs. Lumin, it is not a fair comparison given the multi-generational difference. The Auralic was their 1st gen release while the Lumin was just released. Ultimately, it was the 1st gen Auralic's unstable & chronic SW bugs that became intolerable.

Not surprisingly, the Lumin (with MQA decoding, etc.) has forced a serious look at my DAC. My Metrum Menuet chipsets have two chipset upgrade options but no MQA module option. Metrum Pavane might be the way to go.

I would stay away from MQA for multiple reasons. Although nothing wrong with MQA decoding capability present, just don't use it. With Auralic you are limited to iOS for the controller app, so that should be a major consideration.

But both manefacturers make some great streaming/DAC products, no doubt.

[Pynchon]

Hi Admin,

Good to hear from you.

I have not delved deep on the digital codec side since getting back into audio and only subscribe to Tidal at this point.

Why do you recommend avoiding MQA?

[admin]

Two main reasons:

1) It's a closed proprietary format where the MQA company extorts fees.

2) It's an inferior lossy audio format that is marketed as somehow magically better than lossless.

I would recommend the two part review by GoldenSound on youtube: https://youtu.be/pRjsu9-Vznc

[Pynchon]

Fascinating and much appreciated. This piece certainly resonates as I spent 15 years in video streaming with the myriad of video codecs and video codec compromises & advancements.

Any future move on the DAC and streaming service fronts warrant further consideration.

Thanks again.

Ciao