Empirical Audio Panny Mods

dave_c · « **on:** 14 Jun 2004, 09:36 pm »

I just sent my Panasonic XR45 to Steve for some mods. Not sure when it will get back, but I’ll let everyone know what my impressions are when I get it.

Thanks for answering all my questions Steve!

Here’s a list of mods based on emails:

1. replace input pulse transformer
2. Input buffer is AC coupled to interface transceiver, should be DC coupled
3. replace caps at output filters
4. replace inductors at output filters
5. replace main power supply tank cap with Jensen 4 Pole
6. replace main power supply rectifiers
7. replace lots of HF decoupling and bulk capacitors
8. replace DAC filter caps
9. replace power supply output caps
10. replace binding posts
11. install IEC

I’m also sending in my Monarchy Upsampler to have a USB interface added. I really really hope this works as I’m using my laptop as a source right now and I think this will make a huge improvement.

I'm in San Francisco. Anyone in the Bay Area with a Bolder Panny for some testing?

dave_c · « **Reply #1 on:** 9 Aug 2004, 01:08 am »

Steve has finished the mods on my Panny. Here are his comments based on first listen:

Dave - early report. I only have an unmodded transport to use it with, so it is not optimum. I need to go to Ratshack and get a fuse for my other modded transport.

The sound is impressive indeed. It doesnt sound at all like the original stock version. More like my JC-1 monoblocks, but with a bit less bass control. I would even be happy with this sound. Surprising how good it is. I will give you another report tomorrow when I get the fuse replaced and use my modded transport. Then I can get into details.

Here is a follow up when used with his modded transport

Dave - The sound is really good on the XR45. The image is even more clear with the modded transport. Very little sibilance, if any. The amp is also the quietest I have ever heard - even quieter than other digital amps. It's like it is turned-off until the music starts. Only the highs are not quite a smooth as my reference amp and the lows are not as tight - a bit wooley, but I would expect this with a lower power amp anyway. Very nice indeed.

If you can guess, I'm pretty excited to be getting it back. My report later this week.

TheChairGuy · « **Reply #2 on:** 9 Aug 2004, 02:39 am »

Wow Dave - cool, that's high praise indeed from Steve.

I'm in Marin and have an (unmodded) JVC RX-ES1sl. I wouldn't mind hearing the two digital wonders side by side.

sunshinedawg · « **Reply #3 on:** 9 Aug 2004, 03:57 am »

Don't forget to give it some break-in time. It took mine 3 weeks, 24/7 to fully burn-in. Has Steve tried the Monarchy with the modded 45 yet or was he talking about his transport?

dave_c · « **Reply #4 on:** 9 Aug 2004, 08:29 am »

I believe he was using a Turbomodded DVP7700, but that's just my guess. The Monarchy was shipped out last Thursday so I know he didn't get a chance to try them together. I'm expecting BIG things from this combo!

Chairguy - maybe we can arrange something down the line. I want to make sure things are broken in properly. Plus, I haven't had a system in 2 months!!! I've bought a bunch of music i need to get acquianted with if you know what i mean!

TheChairGuy · « **Reply #5 on:** 9 Aug 2004, 04:34 pm »

Dave,

Yep - understood.

FYI - I have a turbomodded S7700 if you want to hear a bit more of what Steve is hearing on your fab newly modded Panny.

Let me know in a couple months when your toes stop tappin'

AphileEarlyAdopter · « **Reply #6 on:** 9 Aug 2004, 05:47 pm »

This is great news Dave. I am in San Ramon. I have a XR50, I can probably bring this in if you dont mind for a kind of shootout. I should also be getting a Blue Circle Music Ring balanced power conditioner towards the end of the month. I also have a few power cords which we can try. And some Stillpoints ERS clothes as well.

dave_c · « **Reply #7 on:** 9 Aug 2004, 05:56 pm »

Yeah, I think there are a lot of people in the Bay Area so I'm sure we could get a nice littel shootout going. My apt (or my room for that matter)isn't big enough to accomodate too many people so we might have to arrange something elsewhere.

What size Music Ring did you get? I'm really interested in that piece right now. Currently, I have things hooked up to a Powervar Isolation transformer which is only rated at 5 amps (600 watts). The Panny has a really low current draw, but I don't know if the mods changed that. In any case, I'm going to be looking for conditioning soon.

audioengr · « **Reply #8 on:** 9 Aug 2004, 06:14 pm »

Dave - I would recommend against a conditioner for any power amp, including the XR45. What is the reason that you believe you need it?

dave_c · « **Reply #9 on:** 9 Aug 2004, 06:21 pm »

Mostly concerned about the quality of AC in my area. I live in an apt in SF with a lot of computer equipment hooked up to the same circuit. Since I'm renting, I don't really have the option to get a dedicated line run in. Do you think that the conditioning is unnecessary? Maybe just a high quality power cord?

TheChairGuy · « **Reply #10 on:** 9 Aug 2004, 08:24 pm »

Dave,

I don't know what effect all those mods Steve did for your Panny had on 'cleaning' up dirty AC (perhaps, Steve, you can explain?), but on my unmodded/bone stock JVC 'little wonder' the difference thru my BPT-2.0 Ultra is very beneficial.

I don't note any restriction of dynamics (but I should give a longer listen to something very dynamic direct into the wall) and the overall effect is beneficial thru the BPT.

zybar · « **Reply #11 on:** 9 Aug 2004, 09:07 pm »

Quote from: audioengr

Dave - I would recommend against a conditioner for any power amp, including the XR45. What is the reason that you believe you need it?

Steve,

Why do you recommend not having a conditioner for amps?

I use a BPT 3.5 Signature and have ALL of my 2 channel gear plugged into it. When I plugged my amps directly into a dedicated circuit there was a noticeable drop off in the quality of the music.

George

TheChairGuy · « **Reply #12 on:** 9 Aug 2004, 09:44 pm »

You know, for the last hour, I've been playing the JVC without the BPT...just straight into the wall.

The results are mixed. With the BPT, there is a very noticeably lower noise floor, voices are cleaner, instruments are more distinct...all in all, it is more enjoyable.

But, I have notied this on more than one occasion with the JVC thru the BPT, during periods of high dynamic peaks, I hear a 'crackling' distinctly heard. I thought it was just the supposed 100 water just choking on it's natural/reality 50 watt self

However, without the BPT and the same music playing, there is no 'crackling' on those same passages.

I am playing at the '24' level on my 90db efficient Vandy's in a 12 x 10' room...hardly ear splitting volumes.

Again, overall, with the BPT is preferred (particularly on easy listeing discs), but there is no doubt the BPT (15 amp model) is robbing some dynamics from the little wonder. Quite interesting....

Do your mods, specifically to the power supply section, work to achieve the filtering of 'dirty' AC without the need for power conditioning on amps? Crap, I think I turning into technogeek now

zybar · « **Reply #13 on:** 9 Aug 2004, 09:53 pm »

My BPT 3.5 Signature is good for 20 amps and is on its own dedicated 20 amp line.

George

scottpretti · « **Reply #14 on:** 9 Aug 2004, 10:00 pm »

ChairGuy,

Are you still using the CyberPower AVR1500 in your system? I remember you stating something about perfect sine waves from the CP1500.

TheChairGuy · « **Reply #15 on:** 9 Aug 2004, 10:26 pm »

Scott,

I didn't say it outputted perfect sine waves..in fact it doesn't and that is where it may fail in it's mission for us audiophiles. The ExactPower (actually, I think this does something different, too), Furman and, perhaps Monster units do tho...at considerabley higher cost to us.

Despite some saying it works wonders, I think it took away life from the music overall than added it back in. It was trade-off, but that's how I voted on it. It works well in my very modest video set-up tho...better picture on my Sony 24". It's such a modest system that I don't pay attention to the audio in this system, but video improved measureably with it in powering the Monster Cable Power Strip.

Sorry for posting my longwinded answer in your forum, Steve...Scott asked and I wanted to answer it.

audioengr · « **Reply #16 on:** 9 Aug 2004, 11:02 pm »

The reason that I dont like conditioners on power amps is they invariably have series inductors. This will rob the amp of dynamics. The ones that regenerate for use autotransformers to boost voltage are okay, providing they have high enough power ratings. The reason that my power cords work is that they are really low inductance. Most of the time, the transformer and input filters on the amps are sufficient for filtering AC noise. If you are concerned about lightning, put in a lightening arrestor or lightning rods.

AphileEarlyAdopter · « **Reply #17 on:** 10 Aug 2004, 12:26 am »

Steve,
My understanding is that these 'Balanced Power Conditioners' work as an isolation transformer and so have less output impedence than a wall outlet. This is in line with people commenting they have better dynamics and bass using the balanced power conditioners. Also, if at all there were any degrading stuff they are behind the balanced power transfomer. Actually, ExactPower has two devices, one that produces a perfect sine wave and another balanced power conditioner that should be used after this.

I tried a CyberPower 1500W UPS which regulates to the voltage and found that the system in quieter with it. But it does rob the music of dynamics. So I returned it. I have now ordered a 1200W balanced power conditioner from Blue Circle.

Jay S · « **Reply #18 on:** 10 Aug 2004, 10:33 am »

The Blue Circle Music Ring 1200 seemed to help the dynamics of my digital amp...and they had a very clear (and beneficial) impact on clarity, smoothness, imaging accuracy and soundstage depth.

TheChairGuy · « **Reply #19 on:** 10 Aug 2004, 03:53 pm »

Funny thing I re-did my A vs. B with and without the BPT inline....only this time I shut off my 400w mono AudioSource amp driving my sub.

Now, there was only the slightest hint of crackling/distortion on dynamic passages...apparently 15 amp ain't good enough to handle a 400 w AB amp, a JVC Hybrid digital receiver, transport and DAC/Power Supply...I really thought it would be.

George/Zybar, your BP-3.5 is measureably higher amperage ratings so you may not have these problems. AEA and Jay S, I think the 1200 is only 10 amps, so it would sems to overload quickly if you don't have digital amplification on it. A goodly sized AB amp will rob the life out of the system unless you only use source, preamp components on it.

Now I understand what Steve is saying...hell, I'm learning a bit each day now