problem with 30SL G2

phaeton

New Member
Nov 13, 2010
13
0
1
Hi all,

I've bought some time ago a secondhand 30SL G2 (D revision). After some months (yes, my fault to not have checked this before) I've found a problem. Pre is working perfectly apart from the balance, which has a very strange behaviour. If I balance sound towards the left side (for example), and the front panel led cursor goes towards the left side (i.e. the correct direction), there is a very very very very little change in sound balance towards right (i.e. on the wrong direction). Reached the end of the balance control, the sound balance switch completely to the right (i.e. on the opposite with regards to the indication on the front panel led). Same behaviour both with the remote and with the front buttons. And of course same behaviour with viceversa directions.

All cables have been double cheked and are ok.

I've contacted my local Spectral distributor (I live in Italy) but since I've bought my 30SL directly in US they refused to give me any assistance, even if I clearly said that of course I'm willing to pay for the repair. I've tried to contact Spectral via mail with no luck (I'm not english mothertounge so I prefer to write).

All in all, it seems to be a very stupid problem, most probably related to the micro controller and not to the analog circuitry, I can easily live with it, but I would like to repair the pre.

Can you give me any reccomendations or suggestions?

regards
mike
 

ack

VIP/Donor & WBF Founding Member
May 6, 2010
6,774
1,198
580
Boston, MA
It doesn't look like there is anything wrong - this is how the balance control works; suggest you read the manual. Unlike any other preamp, the balance control works by modifying the output by extremely small amounts (I believe 0.05dB). This is so you can finely compensate for small differences in your equipment; for example, I have set mine to 4-steps to the right where I measure 0.660V and 0.661V from either channel with a 1kHz reference input from the DAC. And yes, at the extreme positions, the channel is cut off, unlike what you'd would expect. Basically, the balance control in these preamps is used to fine tune your equipment, not adjust the output of the recording - I think it's brilliant.
 

phaeton

New Member
Nov 13, 2010
13
0
1
Hi ack, thanks for your reply.

So, if I get your answer correctly, you're saying that if I "turn" the balance all the way down to the left, it is absolutely normal that the sound comes out only by the right speaker?

In other word, it is absolutely normal an "inverted" configuration with regards to almost all the other balance control? If I turn the balance control of the two other pre I got all the way down to the left, I get the sound to come out from the left speaker......
 

ack

VIP/Donor & WBF Founding Member
May 6, 2010
6,774
1,198
580
Boston, MA
You are correct. Again, it's in the manual
 

phaeton

New Member
Nov 13, 2010
13
0
1
Ack, many thanks again for your reply, as soon as I'll get home I will check the manual.
 

ack

VIP/Donor & WBF Founding Member
May 6, 2010
6,774
1,198
580
Boston, MA
No problem. Cutting off the right channel at the extreme position of the left channel behaves like every other preamp, where if you turn, say, counter-clockwise you are really attenuating the right channel, and at the end of the counter-clockwise travel the other channel is attenuated to infinity (turned off).

If you think about it, Spectral preamps' balance control essentially behaves exactly the same way as any other's, except that the attenuation steps are extremely small and fine-grained up to the extreme positions left and right. So check the manual and let me know whether each attenuation step is 0.05dB or 0.01dB - I can't remember...
 

phaeton

New Member
Nov 13, 2010
13
0
1
Ack,
sorry, now I understand the misunderstanding.... apologies for my faulty english, I wrote badly what's happening with my 30SL...
When I said "the sound comes out only by the right speaker", with "comes out" I don't mean "attenuates to infinity (turn off)", but exactly the viceversa!!!!
In other words, what is happening with my 30SL is that if I turn the balance all the way to the left the sound disappear from the left speaker (and viceversa). So from your previous comment I seem to understand that my 30SL behaves actually uncorrectly.
 

ack

VIP/Donor & WBF Founding Member
May 6, 2010
6,774
1,198
580
Boston, MA
I get the same behavior - sorry about the confusion, I got it backwards. Yes the behavior is confusing, but it is as intended. Perhaps Bernice can explain why... all 30 series preamps I have had behave the same way, and the dealer demo units as well.
 

phaeton

New Member
Nov 13, 2010
13
0
1
Ah, ok, then my loved (not a joke, I do love it, it's the best preamp I've ever had!!) 30SLG2 is behaving correctly, veeeeery good!!!!!!!
Again, many thanks for your support and patience.

regards
mike
 

mimesis

New Member
Sep 26, 2010
86
1
0
I haven't look it up in my 30SS manual but perhaps the display indicates relative intensity of attenuation in that channel. So more lights on the left side indicate greater attenuation of the left channel.

William
 

phaeton

New Member
Nov 13, 2010
13
0
1
thanks to all for the replies, I've checked in the manual and it actually states that the balance scale is related to attenuation (so viceversa with regards to most part of the other pre), and so going all the way to left means attenuate the left channel till it is completely turned off.

best regards
mike
 

Console

Member
Apr 17, 2017
32
5
23
Timbuktu ;)
Ack, you are a hero! That also first confused me a little (along with the slight inbalance of channels when using my Logitech Universal remote vs. original Spectral remote control). A truly special and sensitive unit! :)
 

ack

VIP/Donor & WBF Founding Member
May 6, 2010
6,774
1,198
580
Boston, MA
A hero for reading the manual? Thanks :D
 

About us

  • What’s Best Forum is THE forum for high end audio, product reviews, advice and sharing experiences on the best of everything else. This is THE place where audiophiles and audio companies discuss vintage, contemporary and new audio products, music servers, music streamers, computer audio, digital-to-analog converters, turntables, phono stages, cartridges, reel-to-reel tape machines, speakers, headphones and tube and solid-state amplification. Founded in 2010 What’s Best Forum invites intelligent and courteous people of all interests and backgrounds to describe and discuss the best of everything. From beginners to life-long hobbyists to industry professionals, we enjoy learning about new things and meeting new people, and participating in spirited debates.

Quick Navigation

User Menu

Steve Williams
Site Founder | Site Owner | Administrator
Ron Resnick
Site Co-Owner | Administrator
Julian (The Fixer)
Website Build | Marketing Managersing