[gcos]

Just some general observations, Blair:

1. I think an online manual is needed esp. for non-standard features like the precision phase splitter.( I have no idea whether my knobs are in the position you tuned it, after 3000 miles !)
2. For insurance purposes a serial no. plate would be useful.
3. ID decals for switches etc. on the backplate
 I am putting this in the forum just in case others have recommendations to make the all-round product more superb.

[Niteshade]

All good suggestions and I am working on them.

Precision Phase splitters: I designed the circuit so that there is no wrong place to put them. Just make sure the pointers in the same position for both channels. I wanted to make this new feature more used friendly based on some comments a previous customer made a while ago about how they like controls to work. I think I put them both all the way over to the left (as you're facing the amp) or close to it. You can't hurt it by experimenting.

More to follow as an online manual is configured.

[Niteshade]

New topic! This will temporarily be for questions/answers regarding the NS-40 and documentation. I will reconfigure this after a manual and better upgrade descriptions are made.

[gcos]

All good suggestions and I am working on them.

Precision Phase splitters: I designed the circuit so that there is no wrong place to put them. Just make sure the pointers in the same position for both channels. I think I put them both all the way over to the left (as you're facing the amp)

More to follow as an online manual is configured.

wow ..glad I raised it..nowhere there now, and by no means in the same position..lol..

[gcos]

Blair,
I found it useful to put a knob with a marker on the bias shaft..makes it easy to see where you are in the bias range and also much easier to turn esp if in a tight spot on a rack. Also any info you can post for the time being on the feedback adjuster ?

[djbnh]

Just some general observations, Blair:

1. I think an online manual is needed esp. for non-standard features like the precision phase splitter.( I have no idea whether my knobs are in the position you tuned it, after 3000 miles !)
2. For insurance purposes a serial no. plate would be useful.
3. ID decals for switches etc. on the backplate
 I am putting this in the forum just in case others have recommendations to make the all-round product more superb.

Blair,
I found it useful to put a knob with a marker on the bias shaft..makes it easy to see where you are in the bias range and also much easier to turn esp if in a tight spot on a rack. Also any info you can post for the time being on the feedback adjuster ?

These are all great questions, and Blair your input will be helpful. gcos - I'll take a hit for not mentioning in the other thread that when I received my amp I did not see any documentation. (However, I only unpacked enough to remove the amp / tubes; I didn't pull everything out after that.)

[Niteshade]

All the controls I put on an amplifier are user friendly. That means there is no wrong setting to put them on. (Except one)

The exception is Tunable Biasing. Tunable Biasing is extremely easy to use though! Simply adjust the bias control for the power tube's sweet spot- where they sound the best and produce the least amount of heat.

NOTE: I have been placing a mark on the shaft of the bias pot and on the housing threads. Initially- match the marks up. Small changes can be made to either side of it for best performance if you feel it is necessary.

The sweet spot has these characteristics:
1. Cool running tubes
2. The most power output
3. Good transient response time
4. Most natural sound

If the control is too far one way, the volume will be reduced and the sound can become distorted. The tubes will run too cool as well. No harm can be done in this extreme.

If the control is set too far the other way the following will happen:
1. Tubes will run way too hot
2. Power transformer will heat up quickly
3. Amp becomes sluggish and too warm sounding
4. Transient response time dwindles
5. Power output is reduced

How to set: Begin at the low/no volume side and move it until the onset of good volume. From here, tweak it backwards or forwards for best performance in very small increments. Once you are used to it, the procedure takes less than a minuet. I can do it in 10-25 seconds.

I will normally have this preset after burn in. These are the instructions to use if the mark rubs off or for tube rolling. Most of the time there is not an issue.

[Niteshade]

Feedback control: Provides the ability to match a speaker system exactly to the amplifier. There is no proper setting, this is done by taste. Tune until you find a good balance between low, medium and high frequencies.

Precision Phase Splitters: Designed to permit optimum power tube drive by allowing the user to manually balance the phase splitter easily. There is no wrong setting due to the way I set them up. Just make sure the left and right channels are balanced (same settings for both sides). Just like the other settings, there is an optimal location and it's easy to find. Adjustments are best made at higher volumes.

[FullRangeMan]

Hi,
Iam thinking the Phase Splitter Control is a adjust for the output tubes load at the output transformer (class AB) in PushPull amps??
Is this right??

[djbnh]

Just some general observations, Blair:

1. I think an online manual is needed esp. for non-standard features like the precision phase splitter.( I have no idea whether my knobs are in the position you tuned it, after 3000 miles !)
2. For insurance purposes a serial no. plate would be useful.
3. ID decals for switches etc. on the backplate
 I am putting this in the forum just in case others have recommendations to make the all-round product more superb.

Question: were the power tubes provided matched?And the other two tubes?

[gcos]

Question: were the power tubes provided matched?And the other two tubes?

I am sure they were but Blair will have to confirm. The 6L6GC are current production JJ chrome tops. The 6SN7s are nos. I am currently listening to Brian Bromberg  'It Is What It Is'....awesome

[Niteshade]

Yes, the tubes are matched. All 6SN7's are NOS and fitted for performance. That means some orders may not get a matched pair of 6SN7's (regarding manufacturer), but they will be 100% matched performance-wise and have the same internal structures and specifications.

Sometimes I may change the power tube manufacturer, but they will be 100% up to specification and the change will be sonically transparent.

[Niteshade]

DC Filament supply: Plug into the amp before plugging into the power strip.

[djbnh]

Blair, what's the size / values / etc of the fuse in the NS-40? I'm considering ordering an after-market fuse, so this information will be helpful. Thank you.

[Niteshade]

The best fuse value would be a 4 amp slow blow or 5 amp fast blow. Usually what takes a fuse out over time is the tun on current rush.

[jtwrace]

Blair, what's the size / values / etc of the fuse in the NS-40? I'm considering ordering an after-market fuse, so this information will be helpful. Thank you.

Consider yourself informed...

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