Which Tubes In Your HX/DA???

Can you elaborate, and also provide a solution to finding the "good times" and making them happen all of the time?!? Pretty please?!?!

There can be AC power fluctuations, but that will vary depending on where you are. Also, there are times when appliances on the same circuit can cause power issues.

Then again, for some folks this isn't applicable at all.

My studio is run off an AC isolation transformer, so I can't say whether that's a problem in my area or not, YMMV. Some folks try to solve the perceived problem with a gizmo like this:

http://www.premierguitar.com/articles/Close_Up_Furman_P_1800_PF_R_Power_Conditioner_Surge_Suppressor

I have no idea if these work, but there are people who swear by them.
 
Can you elaborate, and also provide a solution to finding the "good times" and making them happen all of the time?!? Pretty please?!?!

In Audiophile Land, better sound is achieved....at.......night. During those hours, there are less people on the grid, hence less load, less clean power loss.

A dedicated line to the room good internal wiring (if you own your home)with hospital grade plugs is what you need for 24/7 happiness.
 
In Audiophile Land, better sound is achieved....at.......night. During those hours, there are less people on the grid, hence less load, less clean power loss.

A dedicated line to the room good internal wiring (if you own your home)with hospital grade plugs is what you need for 24/7 happiness.

tab, I'll quibble with this a little. I think that it's true for some locations, and not others, and much depends on the many variations that occur from area to area, even in the same city. An old power transformer in one location can be very noisy, and another location can have new power line equipment and be less susceptible to issues.

I do agree that a dedicated line with good wiring is a good thing in any circumstances, but sometimes it won't make a difference. In fact, the main reason to install a dedicated line is so that the power amplifiers in an audio system can draw the full current.

It can't hurt to install hospital grade plugs, because the construction methods have stricter requirements, but again, I've yet to hear an audible difference caused by installing a set. They're certainly more dependable and reliable!

Based on experience in my studios over the years, I've found the best solution to audio problems is twofold, but they're usually combined into one product:

Power everything with a dedicated isolation transformer with balanced power.

An isolation transformer takes the power coming into the house and then isolates it from the power line, regenerates it into clean power with no noise, and has its own receptacles. Balanced power is a recent (approved by electrical codes only since the 90s) development pioneered by Equi=Tech, and Furman also makes products that have it. Balanced power works like a balanced audio line to kill noise. So noise isn't radiated into, for example, audio cables and reproduced as hum.

I use a 1000 volt isolation transformer with balanced power receptacles, which is plenty for my studio now that most of my work is done "in the box." When I had more analog gear, I had a 2000 volt isolation transformer, but it was very heavy (about 150 pounds) and generated some mechanical noise, so I had to isolate and soundproof the room it was kept in. The one I use now is completely silent. It weighs about 75 pounds.

I run not only my studio gear with this thing, but also my guitar amplifiers. These run around a grand, and are the most effective $1000 I've ever spent in my studio at giving me good audio.
 
Depending on which Equitech(I have one on my TV and Xbox), a dedicated line could be cheaper option with good plugs(not the garbage from big box stores). P.S. Audio makes great products and used to make balanced regenerator's that beat Equitech. Garbage in, garbage out.
 
Depending on which Equitech(I have one on my TV and Xbox), a dedicated line could be cheaper option with good plugs(not the garbage from big box stores). P.S. Audio makes great products and used to make balanced regenerator's that beat Equitech. Garbage in, garbage out.

Unfortunately, a dedicated line doesn't balance the power and thus eliminate line noise. Nor does it eliminate hash and noise coming in from outside. All it does is eliminate sources of noise like appliances, lights, etc., in the home from the outlet attached to the dedicated line.

My tech measured about a 10 db noise reduction in my studio with his oscilloscope when I first went with balanced power in the 90s. That is very significant for a recording studio. And I had a dedicated line going into my studio prior to that, as well as a star grounding system with a very solid earth ground. I've used SOLA, Furman and Equi=Tech iso transformers and balanced lines. The SOLA was an industrial piece of equipment that was modified to have balanced operation, and was my first experience with it.

I noticed no audible difference in any of these units, nor could we measure a difference on a 'scope. The Sola became just too mechanically noisy, and it was in a room with soundproofing, but began to vibrate the floor! The Furman also developed a mechanical buzz. The Equi=Tech has not exhibited these problems. The model I have is the Q.

I'll take the assertion about the difference between the PS and any of these other units with a grain of salt. When it comes to power issues, I don't buy the audiophile-approved line, though I am an audio fanatic.

Then again, I don't have Shun-Mook wooden disks, I don't have wooden dowels on stands scattered around my room, nor do I put my cables up on little magical wooden blocks to isolate them from the floor. I'm sure that stuff all works in some folks' heads, but I'll take measurements, thanks. ;)

Incidentally, I'm a person who does hear differences in cables, and regularly won bets with my tech over whether I could identify them in double blind tests in a statistically significant way, until he gave up testing me. So there is some voodoo I am into. I just only will go so far in this religion. Then again, I was a guy who had Magneplanars, Ohm Fs, Citation 11s, B&W 801s, and other audio exotica of the time back in the 70s and 80s, and none of it sounded one tenth as true to the source as today's moderately priced near and midfield studio monitoring equipment. So maybe I'm just over it.

Again, I've noticed no subjective improvement in audio whatsoever from plugs of any kind, big box, hospital grade, or any others. Nor were we able to measure any differences in power using a variety of plugs in my studio. I think it's one of those "feel good" things, however, I don't discourage anyone from feeling good about their power equipment. It can't hurt to have high quality plugs.

One might wonder about the importance I place on noise - it is my contention, that I've realized over the past 27 years of making my living in the recording studio, that things sound better when there is less noise. A note that comes out of inky blackness tends to sound better than a note that comes out of a background of hash, hums and buzzes.

For some guitar amps, that are inherently noisy, it doesn't matter much what they're plugged into, they sound like they have noise problems from the start. My HXDA, and DG30, on the other hand, are very quiet amps, as were my Two-Rocks and a few others. I think that even the subtle background noise in most electrical systems contributes to a psychoacoustic impression that "something's wrong with my tone/sound/etc."

This is why so many people get their best sounding audio in the evening - people aren't running their appliances so much, and there's just less electrical noise. It's not just a matter of clean power, noise is a culprit.
 
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My issue isn't with noise (well maybe it is and I don't realize it) but my amp can get "grainy" and "harsh" depending on __________________.

I haven't discovered it to be a specific time, place etc... It sounded GREAT at our last practice, grainy early on at our last show, then GREAT at the very end of the show. There appear to be frequencies (I've identified these frequencies in every Marshall or Marshall based amp I've ever played) that are sensitive to something. I'm not sure what they're sensitive to, but I wish I could eliminate it!

I will liken it to when it sounds harsh, I need to roll my tone knob down to 4 to eliminate the harshness of those frequencies. When it sounds great, I can roll the tone up to 10 and the amp sounds way clearer and doesn't have those frequencies spiking. The amp sounds very similar in both scenarios, only it sounds clear in the second scenario.
 
My issue isn't with noise (well maybe it is and I don't realize it) but my amp can get "grainy" and "harsh" depending on __________________.

I haven't discovered it to be a specific time, place etc... It sounded GREAT at our last practice, grainy early on at our last show, then GREAT at the very end of the show. There appear to be frequencies (I've identified these frequencies in every Marshall or Marshall based amp I've ever played) that are sensitive to something. I'm not sure what they're sensitive to, but I wish I could eliminate it!

I will liken it to when it sounds harsh, I need to roll my tone knob down to 4 to eliminate the harshness of those frequencies. When it sounds great, I can roll the tone up to 10 and the amp sounds way clearer and doesn't have those frequencies spiking. The amp sounds very similar in both scenarios, only it sounds clear in the second scenario.

Sounds like dirty power. You need a conditioner as part of your set-up. I'll send you some options.
 
Sounds like dirty power. You need a conditioner as part of your set-up. I'll send you some options.
Yes. Depending upon your locale, the tolerance is somewhere around +/-7VAC so you can have a 14V swing and it still be acceptable. And since the standard is between 110V and 120V, the potential swing is HUGE (103V to 127V). Tube amps hate inconsistency and you're hearing how badly they compensate. The solution: regulation.

There are lots of high quality "conditioners" but since I'm in the computer industry, I have access to gently used uninterruptible power supplies (UPS). Made for expensive servers with even less tolerance for noise and voltage fluctuation, they are cheaper (economies of scale...more server racks in the world than guitar racks) and very well built. Plus, they have battery backup that will keep a rig running for a few minutes in the event of a power episode. I take an APC Smart UPS 750 and it has worked perfectly for years. I'll take a 1500VA model if I need to cover the other guitarist and bassist. There's one in my man cave that powers everything and has saved my gear many times from bad power accidents. Used, you can find one for less than $100. Ask your work if they have an old one they are pitching. A replacement battery is all you'd need.
 
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You know, the term "dirty power" sounds kind of...fun...

By the way, speaking of tubes, I scored some matched NOS Siemens EL34s for my HXDA. I'll put them in when I notice wear on my current set.

I'm still hunting for a good set of NOS 12AX7s that will be worthy of the amp. Meantime I'm using the JJs that come installed in the amps (and periodically replacing them because they tend to not last!).
 
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As an aside, I am changing out the metal oxide resistors for carbon comps, and probably lowering some of the filtering values on the amp to see if that takes away some of the aggressiveness.

Also, I have misplaced the preamp tubes that I ordered, so now I have to order more!!!
 
I'm still hunting for a good set of NOS 12AX7s that will be worthy of the amp.
I have a stash of CCa's from my 12AX7/EL84 tube amp days which I am never parting with so don't ask. I do recommend the 12AX7LPS -- it's worth trying for the price.

lso, I have misplaced the preamp tubes that I ordered, so now I have to order more!!!
I hate when that happens. Now where IS that stash of CCa's...
 
I have a stash of CCa's from my 12AX7/EL84 tube amp days which I am never parting with so don't ask. I do recommend the 12AX7LPS -- it's worth trying for the price.

I hate when that happens. Now where IS that stash of CCa's...

I found some NOS Mullard CV4004 military grade 12AX7s. I'll order a set if my royalty check is decent next week. ;)

Also...I started keeping all my spare tubes in one box in one cabinet in my studio, and haven't misplaced any since doing that! Before I had them in various cases and carry bags for sessions/gigs and I don't know what happened to half the stuff I had in them!
 
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I think my dog ate them. Seriously!

Tonight was one of those nights where the amp sounded great. Had the treble almost dimed, mids dimed, bass at noon, presence full up. I wished the volume went to 14! It sounded spectacular!

Tuesday night, same room, same guitar, same everything; I had the presence OFF, bass at 8, mids at 3-5 ish, treble 2. Had to roll the tone on the guitar down to 3.

I need more nights like tonight.
 
The gold eagle was the Anniversary "badge" and the first HX/DAs were modded Anniversary models, so you have an early model. Do you have smooth rotation master pot or the detented rotary attenuator?

My SuperD is dated 11-06 and is a CAD creation, so there were a lot of great things coming out of the amp department that year.

The master is smooth, just the same as all the other pots.
 
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