[Daygloworange]

I wasn't even aware of this polarity flipping thing. Thanks for the info, guys.

Cheers

[spwal]

I have the Red Wine Audio SB2 and my friend has the Bolder SB3.  we have done a bunch of a/b tests and have come to the conclusion that both are very worthwhile mods and certainly are neccessary if you go this route.

He is additionaly running his with a Bel Canto DAC2.  He has other practical reasons for having a DAC2 in this setup, but i have been perfectly satisfied with the upgraded DAC in the modification.  I have owned 2 Wadias and 2 Bel Canto DACs, and I have to say that this is really the last worry on your mind...

Close your eyes and buy.  make sure the rest of your gear is up to spec (in a sensible sane way) and you will be delighted with your results.  Black Gates take some time, until then they sound taut, but after a couple weeks you will never look back.

Name me one person that went back from a well-executed SB setup to CDs... I bet there isnt one...

[TomS]

V15 is actually for the firmware in the Squeezebox itself.  AFIK the server software doesn't matter with regard to polarity, but stability is another matter entirely.

[mcgsxr]

In this case, it actually does matter - the V15 does invert phase, I use it myself, with my modded SB3, so the ultimate polarity is the same as with other sources etc.

I have not had issues with stability either, once I sorted out a repeater for my network, and moved to the Linksys 54S router.

[Wayne1]

Please read the sticky here for information about the polarity inversion, firmware and SlimServer.

Quick background: with the mods I do the op-amp is removed to obtain better sound. In the original design of the SB, the op-amp inverts the signal coming from the DAC chip. The designers of the Squeeze Box were not aware that this was a "problem" until some users pointed it out. They finally started inverting the signal coming out of the DAC chip in Firmware 24. This was so users of stock SB would be able to obtain the correct polarity.

A lot will depend on your system. Quite a few pre-amps do invert signal polarity. I do suggest you listen to your system and switch polarity with your speaker cable and find out what works best for you. You can then decide what firmware to use with what version of SlimServer.

mgalusha's firmware selector makes changing the different firmware very easy.

As with a lot of cutting edge products, the modded SB is not entirely plug and play. There are lots of options to allow the end user to fine tune the product to THEIR system. It does take a bit more time and it does have a slightly steep learning curve. I do believe the results are worth it.

[NewBuyer]

Personally, I really would not want to always need to use a certain old version of software/firmware and a separate workaround firmware selector program. I would much prefer to just keep using the current and future software/firmware releases and the benefits and bugfixes these revisions will bring. SlimDevices (now Logitech) is constantly updating/upgrading their SB software and firmware, even on a nightly basis - this is actually one of the most appreciated things about their company.

Wayne, after op-amp removal, is it genuinely impossible, or somehow too difficult, to still mod the SB3 in such a way that correct polarity remains? 

I think users would pay a little extra for it too...

[Wayne1]

The analog mod I do removes the op-amp and runs the output of the DAC chip direct to the output jacks through very high quality capacitors.

This gives the best sound. With the stock analog circuit in place, the sound is nowhere near as good, IMHO.

Using the latest firmware, software etc, may not always be the greatest. A lot of the nightlys released are still buggy.

For myself, I prefer to used a tried and true piece of software rather than something than "may" be an improvement.

I once upgraded from software 6.1 to 6.2. It was a major mistake in my system. There was a great deal of drops. The only way I could listen to my system was to "downgrade" and go back to the old software. It used up many hours on my part to trouble shoot and fix this "upgrade".

There are many ways to go about maintaining "correct" polarity. You can keep the SB analog section stock. You can have the analog section modded and use a tube preamp that inverts polarity (as quite a few do). You can add a 1:1 transformer after the analog output and wire it for reverse polarity. You can use the digital output to an external DAC.

With the op-amp removed, another stage does have to be added in the circuit somewhere to invert the signal. This can be an op-amp, transformer, tube, or transistor. 3 of the four options would require another power supply and additional circuitry. All require a fair amount of additional cost.

At this point, my concern with the mods is to get the "best" sound. For now, that involves a polarity inversion with the "latest" software. There are many ways to work around this. Most of my customers seem to be happy with this. If you are not, then I am sorry.

I am contemplating an additional "add-on" product that would address this and other "issues" with the analog modded SB. It may be six months or more until this product is ready to be released.

[Robert57]

As I am awaiting eagerly to get back my own Bolder SB2's from Wayne, I too am worrying a bit about this polarity issue. But I also read some strong comments on the Slim Devices forum that raise questions about how detectable this inversion really is. Many think it is a non- issue, and that tracks often have such a jumbled recording process in some recording studios that one can easily have a mix of polarities on the same album. It does seem very appealing in theory to have a "correct polarity", but I'd like to hear from people who have done actual listening tests with a fixed firmware, inverting polarity by switching speaker connections. Maybe it's a non-issue. Firmware 15, I believe, included other subtle volume adjustment differences, apart from the polarity inversion, that may account for its preferred sound by some.

[NewBuyer]

...There are many ways to go about maintaining "correct" polarity...With the op-amp removed, another stage does have to be added in the circuit somewhere to invert the signal. This can be an op-amp, transformer, tube, or transistor. 3 of the four options would require another power supply and additional circuitry. All require a fair amount of additional cost...

Hey thanks again Wayne for the information! I am not a DIY'er (yet), so until you said this, I had absolutely no idea it was all this difficult to reverse the polarity at an RCA output.  It's way more complicated than I had imagined!

Yes, I too read that enough SqueezeBox users complained to SlimDevices about the reversed polarity firmware bug, that SlimDevices finally felt compelled to fix it. For some reason it mattered alot to enough users, so personally I would like to keep the fix, and thus use current and future software/firmware versions (also for current and future fixes/enhancements). For me, I'm more interested in "keeping it simple" with the SB3, without needing to factor-in additional software workarounds etc. (I'm probably just lazy! ) The new Transporter looks really good too.

Like others, I must wonder if polarity reversal can be generally audible. Many say they can hear correct polarity and prefer it. I'm curious how much it can (in theory) contribute. Some professional equipment reviewers say correct polarity is very noticeable (i.e. to the reviewer), but who knows? Perhaps there is nothing audibly "wrong" with reversed polarity. 

...I am contemplating an additional "add-on" product that would address this and other "issues" with the analog modded SB. It may be six months or more until this product is ready to be released.

Thanks also for mentioning this possible future add-on product that will address this and other "issues" with the analog modded SB. Would you be comfortable saying in advance, to all of us here, what the product will be (and what it will do)? Sounds like it might be worth the wait for me. What other "issues" are you referring to with the analog modded SB?

[TomS]

It sure would be nice if Slim would just put a setting in the firmware to allow it to be switched either way.  Maybe some software guru could write a plugin to do that.

[Wayne1]

It sure would be nice if Slim would just put a setting in the firmware to allow it to be switched either way.  Maybe some software guru could write a plugin to do that.

Tom,

There IS a polarity "switch" in the latest SlimServer for the Transporter. You can change the polarity, BUT only for the Transporter.

I used this option at RMAF so I could compare the Transporter to the modded SBs.

I do not feel it is appropriate to discuss specific BOLDER products in the general areas. This discussion has mostly been about the SB in general.

I will be starting a topic in the BOLDER Circle to discuss the possible add on item.

[TomS]

Wayne,

Sorry about that.  This thread went so quickly in the direction of "mods" and Bolder I didn't realize I was NOT in your circle