[thesteve]

Originally Posted by birry

Yeah, it is crazy. I don't understand "how" it works, I just understand that it works like that and don't try to understand the reasons. Am I understanding correctly that the L-pad type attenuator is adjustable? I'll probably try it first and if I have trouble with it, maybe do the fixed one with just resistors.

Also, has anyone on here done the volume knob mod where you change it out for an audio taper pot instead of the linear one that comes in it? I've read that the clean channel uses an audio (correct) one but the dirt side uses a linear (incorrect) one, but my amp seems exactly the opposite. I'd love to get rid of the ridiculous sensitivity between 2 and 4 on mine.

The L-Pad is basically potentiometer, so yes it's adjustable. Still, I kept mine set for about as much attenuation as possible.

I never did the volume knob mod. I found both channels to be very sensitive to adjustment to the volume knob. The drive channel "master volume" is probably less sensitive because it's also controlled by the drive knob.

[birry]

Originally Posted by thesteve

The L-Pad is basically potentiometer, so yes it's adjustable. Still, I kept mine set for about as much attenuation as possible.

I never did the volume knob mod. I found both channels to be very sensitive to adjustment to the volume knob. The drive channel "master volume" is probably less sensitive because it's also controlled by the drive knob.

What about the transformer attenuator? I've never seen anyone mention it on this board. It seems like there are several ways to build them, but the L-pad seems to be the most common around these parts!

Also, you're probably right about the drive channel and master volume interaction. I forgot about that.

[thesteve]

Originally Posted by birry

What about the transformer attenuator? I've never seen anyone mention it on this board. It seems like there are several ways to build them, but the L-pad seems to be the most common around these parts!

Also, you're probably right about the drive channel and master volume interaction. I forgot about that.

I'm not really familiar with transformer attenuators. From just a cursory look at them, it seems like they're a much more expensive option.

I really don't understand why Fender calls it the "master volume" on the HRDs. It seems like a lot of people who get the HRDlx or are looking into it don't understand that it only applies to the drive channel and not the normal channel.

[Stratopastor]

For the record, the term l-pad is used whether it's fixed (2 fixed-value resistors) or adjustable. Mostly on this forum we mean the rotary adjustable kind.

No idea what's going on with that 'transformer attenuator' idea but I suspect it doesn't do what those forum guys think it does i terms of preserving the impedance. Also the Radio Shack wall-control (in that same thread) is probably just a low-powered rotary adjustable l-pad and has no transformer...

[birry]

Originally Posted by Stratopastor

For the record, the term l-pad is used whether it's fixed (2 fixed-value resistors) or adjustable. Mostly on this forum we mean the rotary adjustable kind.

No idea what's going on with that 'transformer attenuator' idea but I suspect it doesn't do what those forum guys think it does i terms of preserving the impedance. Also the Radio Shack wall-control (in that same thread) is probably just a low-powered rotary adjustable l-pad and has no transformer...

Yeah, I wasn't sure if I could trust it (even though it IS on the internet). Just to clear something up if I haven't already: I am running my Epi Les Paul to the mono input on the Line 6 M13 then mono output from the M13 to channel 1 on the HRDlx. I only use the clean side of the amp and get all my distortion tones from the M13.

Now....I have some stupid questions.

1. What's the difference between inputs 1 and 2 on my amp? I've always just plugged into 1, but for no good reason.

2. I was under the impression that I could reduce my overall volume by "throwing away" some of the power with an attenuator before it gets to the speaker. That way I could turn the volume knob up a touch, push the tubes a little more, and get better tones out of them at lower volumes. Is that only valid when using amp distortion or will it work with the cleans and other effects from the M13?

3. Finally - will using the effects loop on my amp have any impact on either of the above questions?

Every time I think I've got something figured out, you experienced/electrical people just throw me for a loop! We need to start a thread titled "birry is dumb. please help him become less dumb."

[thesteve]

No such thing as stupid questions, just stupid people who ask questions

Originally Posted by birry

1. What's the difference between inputs 1 and 2 on my amp? I've always just plugged into 1, but for no good reason.

The difference between the two inputs is 6db. If you run two instruments into them, both inputs will be the same but if you plug directly into input 2, then your signal strength will be 6db lower. This is designed to give active instruments, which typically have a stronger input signal, a little more front end to deal with. If you take your current signal chain and run it into input 2, it might give you a little more room to play with the volume knob.

2. I was under the impression that I could reduce my overall volume by "throwing away" some of the power with an attenuator before it gets to the speaker. That way I could turn the volume knob up a touch, push the tubes a little more, and get better tones out of them at lower volumes. Is that only valid when using amp distortion or will it work with the cleans and other effects from the M13?

It will work fine with the clean channel. I don't know how the overdrive channel on the III series is, but on previous incarnations of the HRDlx, it wasn't anything special. When I owned mine, all my dirt was provided by pedals.

3. Finally - will using the effects loop on my amp have any impact on either of the above questions?

Nope. I'm not sure how well the M13 would do in the loop alone. I'm assuming you're talking about using the effects loop with other pedals besides the M13.

[birry]

Originally Posted by thesteve

No such thing as stupid questions, just stupid people who ask questions

The difference between the two inputs is 6db. If you run two instruments into them, both inputs will be the same but if you plug directly into input 2, then your signal strength will be 6db lower. This is designed to give active instruments, which typically have a stronger input signal, a little more front end to deal with. If you take your current signal chain and run it into input 2, it might give you a little more room to play with the volume knob.

It will work fine with the clean channel. I don't know how the overdrive channel on the III series is, but on previous incarnations of the HRDlx, it wasn't anything special. When I owned mine, all my dirt was provided by pedals.

Nope. I'm not sure how well the M13 would do in the loop alone. I'm assuming you're talking about using the effects loop with other pedals besides the M13.

Really good info, thanks!

What I'm trying to do, like most everyone else, is find the most practical and best sounding guitar rig I can have with my current setup. I'll run through it a little more specifically and see if you guys have any other pointers for the volume/tone issue.

Les Paul - selector switch in middle (both pickups) with all tone and volume knobs at 10 except when I play distorted chords, I turn down the neck pickup to around 7 or so

M13 - sometimes I use a tube compressor for certain clean tones, but usually not. For other effects, I turn down their output/level quite a bit in an effort to reduce some of the noise/volume that the amp is producing. My goal with the M13 so far is to get all my effects to be around the same perceived volume when playing single notes or chords as compared to when I bypass all effects and do the same thing clean from guitar to amp. I don't want to have some ridiculous jump in volume when I add/remove an effect unless I purposefully add some "thickness" to the mix with a chorus or delay.

HRDlx - using only the clean side and channel 1, volume around 2, treble around 7, bass around 5, and mids around 5 or 6.

This is how I've achieved a decent tone, but I'm not sure if there's a better way to do it. Putting the attenuator in might allow me to get over the 2.5 - 3 volume range of the amp, where I think it sounds best. I played it between 4 and 8 yesterday and it was so loud I couldn't even tell if it sounded good or not. 3 is bearable and I'd like to get that tone, but with less volume.

Sorry to be so long-winded, I just have tons of questions! Last one for this post.....

I would ultimately really like to have a volume pedal. I know people say that it can all be controlled with playing and guitar volume, but I'm not good enough to do really subtle worship-style playing and frilly ambient stuff in a worshipful moment without screwing up and I want to be able to sneak in and out using a volume pedal! My goal is to make our worship times better and NOT distract people. Where is the best place to put that in my chain if I get one?

[thesteve]

Before I hit on the volume pedal question, a comment on attenuators and hitting the amp's sweet spot.

One of the difficulties of using an attenuator, and something you really won't know until you try it, is whether or not the sweet spot you're hitting is a tube-related thing or a volume related thing. Our ears, to an extent, like volume. An attenuator will allow you to get the amp tone you achieve at a higher setting without the volume, however because of the way our ears work, there is a chance that what you're hearing and liking isn't merely amp tone but the sheer volume. Many people who get an attenuator don't understand this and in turn complain about an attenuator "sucking their tone" when the reality is simply that it's the lack of volume that gives way to the perceived tone suck.

Now, if you want to use a volume pedal for ambient swells and the like, my recommendation would be to put the volume pedal in the effects loop of your M13. This would put it between the drive pedal section of the M13 and the modulation section of the M13.

[Major Tom]

I agree with Stratopastor - I don't believe that those in-wall speaker transformers are suitable for tube amps - as far as I know, they do not preserve a constant impedance, they increase the overall impedance as you increase attenuation. They are made for solid state amps which can operate at any impedance above their minimum rating. Maybe someone can buy one and measure it.

You might try either turning down the overall output level on your M-13 or plugging into input 2, that may reduce the sensitivity of your clean channel volume. The reason I believe that you find the clean channel volume to be sensitive is that that is a LOUD amp. Loud amps don't do bedroom or church levels very well.

As far as the sound of it at 3.5 - 4 vs. 2.5, Google "Fletcher-Munson effect". Basically, our ear's freq. response varies with sound pressure level. Guitar amps are not engineered to sound good at low levels...and for that matter our ears are not engineered for guitar amps sound good at low levels.

You can use a power attenuator to help with your overall volume, however, if you use a pedal to generate your distortion and then feed that into a clean amp whose power section is not driven into distortion, IMO there is no point to using power attenuation. Might as well just turn the amp down. I think you will find that turning the amp's volume to 3 -4 where it sounds good to you now, and then using an attenuator to lower it down to bedroom or church levels, it won't sound any better than it does to you now when set to 2. The reason is the Fletcher Munson effect that I mentioned above. The Lpad attenuators only cost like $20. to build though, so its not like its a major investment....

My personal recommendation would be to use the amp's own overdrive/distortion instead of getting it from the pedals; for that, an attenuator would be quite useful. Pedals use circuitry to mimic what tubes do when driven into saturation....why not use the real thing?

As far as the power handling of the 100 watt Lpads. As some of you know, back in the day, I built and sold quite a few of these, both on this forum, and ebay, many to be used on HR amps. Guys using full-on distortion tones complained that they overheated and smoked. Players using clean and moderate OD tones (like me) had no problems. I tested it with mine, and yes, with full distortion, driving the power tubes into saturation they will indeed overheat and smoke. They will not handle 100 watts of continuous power.

[birry]

Just an update: I used the HRDlx at church this morning and it sounded great. The worship leader and I discussed it and decided that I could have been louder, even. I only had it just a shade over 2 on the clean side volume knob. I might take it up around 3 next Sunday and just turn down my mic a little.

Yes, its loud, but I'm tired of shopping for amps now and I think I'll stick with this one. It has near-perfect (for me) tones and the volume issue can be worked out, especially live. I may swing through GC to play an Egnater before my 30-day thing is up, but for now I'm pretty happy that this amp worked when mic'ing it on stage. I'll have to do it this way until we get a building (hopefully in August).

A volume pedal would still be immensely valuable, I think.

And something with single coils....

But that's way down the road, I guess.

[Stratopastor]

Tom, it crosses my mind that those "transformer attenuators" are actually small rotary l-pads with a "100v line" step-down transformer in the same package. What do you think?

[Major Tom]

Originally Posted by Stratopastor

Tom, it crosses my mind that those "transformer attenuators" are actually small rotary l-pads with a "100v line" step-down transformer in the same package. What do you think?

Not sure at all. Ironically, I have installed quite a few of the stereo ones. but I didn't "design" the sound systems, only hooked 'em up and never paid much attention to them. Someone told me that they increase the impedance as you turn the volume down, for what very little that is worth.

[Stratopastor]

Thanks... :-)