Concept Tread: Features of the Perfect Tube Amp?

Benjamin Davidson · Post by **Benjamin Davidson** » 24 Jan 2021 9:56 am

I would like to focus this discussion to feature sets, or output section requirements (i.e. tube configurations, or wattage thresholds), to features like EQ stacks or effects loops. Specific amplifiers being recommended isn't what I'm looking for here, but those recommended amps specific amplifiers features sets will be looked at closely.

I'm in the market to find a new amplifier. When live music starts again I want to be able to work with reasonable volume level. A single amp I can play at the house, in the studio, and mic'd up on stage with a very low noise floor. I will explain why nothing on the market quite fits my needs below. So, I'm looking to build an amplifier specific to this purpose and this thread is a tool to make sure I haven't overlooked anything, or look at options I haven't considered yet.

What features would make a Perfect Tube Amp for Pedal Steel?

And now the backstory to how this thread came about:
You would assume that there are multiple amps available on the market that could do this easily, that new Fender '68 Custom Pro Reverb looks great for this very thing. Well, a few months ago I started running two amps in a Wet/Dry configuration (Un-modulated signal into one amp, Delay/Reverb signal into the other amp, and split by an isolation transformer device to the dry amp - ground connection direct to the wet amp).

This is the best steel sound I've created. I get the pure sound of the steel out of one amplifier, and I get the modulated sound (particularly Reverb) out of the other amp and its just sounds amazing. I simply don't have the headroom and EQ controls that I would like to have available. So, I am planning to build a single amplifier with two pre-amp and two power-amp sections that would allow me to run traditional mono through both, utilize my wet/dry set up, or even stereo with minimal cable routing changes out of my pedalboard.

Steve Lipsey · Post by **Steve Lipsey** » 24 Jan 2021 12:08 pm

Why do you need two power amps? Wouldn't two preamps be enough? E.g., fender amp with one reverb channel and one other channel, if amp reverb is what you require?

Benjamin Davidson · Post by **Benjamin Davidson** » 24 Jan 2021 12:14 pm

Steve,

Two separate power amps allow that each of those signals remains its own, and goes out to a separate speaker. Two power amps also allows me to run stereo if required.

I have done this with my deluxe reverb alone, as my isolater has a phase reverse switch. However, it still doesn't have the same effect has having two separate power amps.

Post by **Dave Mudgett** » 24 Jan 2021 1:07 pm

For my own listening pleasure, I enjoy running double amp setups if I have the room and desire to schlepp stuff. Two power amps into separate speakers do sound great, at least in the near field. But I'm not sure it makes so much difference once you get 20+ feet out unless the speakers are well separated.

For what you're looking for, I think you're on the right track with a Deluxe Reverb type of platform. A Deluxe Reverb style amp with a 2x6V6 power amp section associated with each preamp section, each into its own 12-inch speaker. One could keep the weight down some by using good neo speakers. But it ain't gonna be light. I'm sure there are a number of design issues - transformer selection, component layout, heat, and so on. Personally, I'd probably just prefer to drag along two Deluxe Reverbs, or maybe a Deluxe and Vibrolux, or even a Deluxe and Princeton Reverb, if I need more juice, and have been known to do that.

I have an early-mid 60s Ampeg Super Echo Twin, which is definitely stereo, with two 7591 power amp sections. It's a beast, and not really the tone I prefer for pedal steel. And it's as heavy as my Twin Reverb.

Jim Kelly made 4x6V6 amps back in the 80s. I played a couple, sounded very good, but I don't think they were stereo, if I recall correctly.

Don't laugh, but a nice Roland Stereo Chorus 120 is good for that kind of thing. Another nice amp I used to use some is the Peavey Stereo Chorus 400 (or the slightly later 212). Of course, not tube, but won't break that bank and sound good, IMO. But not light either.

I have thought of using my Quilter Tone Block (I have a 201) with a small cab to augment my Deluxe Reverb. But lately (well, last summer lately) I was lazy and just used the Quilter. Maybe not quite as sweet as a Deluxe, but really quite surprisingly good, to my tastes.

Mike Schwartzman · Post by **Mike Schwartzman** » 24 Jan 2021 4:49 pm

What features would make a Perfect Tube Amp for Pedal Steel?

Often times here on the the forum many players love the Twin Reverb (SF, BF) for psg. Either stock or add a couple of JBL's, and the weight is pretty impossible for me (bad back).
So a couple years back, I took up a little experiment on getting a 2 x 6L6 Fender amp with reverb to be very steel friendly. I had already knew that a SF Deluxe Reverb sounded really nice with PSG and want just a little more clean headroom. I started with the platform of an early 70's Bandmaster Reverb.
I replaced the stock 4 ohm output transformer to a Bassman OP. Put a 5751 preamp tube in V2 and put it in a combo cab with a EPS-15C speaker, which is a very efficient neo 4 ohm speaker. The stock reverb tank was replaced with a MOD tank, which turned out to be an upgrade. I had restored the amp to black face specs prior to those changes, and used very strong older tubes all around.

Is it the perfect tube amp for PSG? Nah...but it's definitely quite good because the extra clean headroom is there and the tone is beautiful. Downsides are even though it is much lighter than a Twin Reverb, it is definitely not a flyweight, and the mid control is only provided on the vibrato channel not the normal channel. There is a bonus though. In a small to medium room I wouldn't hesitate to use that amp for double duty...that is PSG and Tele. Sounds great for either.
I've not heard the '68 Custom Pro Reverb, but I would think it would be similar to what I've described here except for the speaker configuration. Enjoy the journey.

Jim Sliff · Post by **Jim Sliff** » 24 Jan 2021 10:23 pm

I'm in the market to find a new amplifier.

if you play more than one size and configuration of venue and/or more than one style of music (or with more than one band) you will; almost assuredly ned MORE than one amp - AAND a good tech to work with to optimize each setup.!

It's a complicated subject but the basics are this:

You want an amp - and for tone a good tube amp - running near the top of its headroom when running clean with whatever speaker(s) sound(s) best - and that takes analyzing playing technique, guitar setup (pickup and height etc), style of music being played, the OTHER musicians in each situation and what they use/how loud they play; house sound support; size, shape, ceiling height, wall surfaces (drywall, covered, wood, glass etc) - and audience size!

6-string players have been using 3-5 finely-tuned gig amps and precisely set up guitars for decades just to get optimum clean tones unless thy only play one place with one band - and with generally the same sized audience.

A professional tech is an equipment optimizer/repairman/consultant. find a good one, work with him/her, and you'll probably be amazed at the overall improvement in your tone.

There will be many steel player who will think the whole idea overkill and silly - but that's because the steel world has pretty much done the same thing the same way for decades with only minor variations on a theme, with many playing $4,000 mechanically-slick guitars through $800 amps, thinking thinking guitar players using $2000 guitars though $2500 tube amps (after setup) is absurd!

Do the math...

Benjamin Davidson · Post by **Benjamin Davidson** » 25 Jan 2021 2:24 pm

Dave-
Focusing my options on 2x6V6 like the Deluze or 2x6L6 like the ProReverb. Speaker is gonna be a TT12 on the drive, and a Texas Heat or another TT12 for the Reverb side. I like the sound of that combination.

Mike-
Thanks for the info on your experiance, I'll look into those specific amps more closly. I actually run the 5751s in all my preamp tubes on the Deluxe Reverb.

Jim-
I totally understand your position, and should I get to have the workload to support that sort of specialization, I'll revisit that recommendation. I play for myself mostly, and a small church congregation when I get the chance - so I think I can get a single amp to work for now.

Benjamin Davidson · Post by **Benjamin Davidson** » 28 Jan 2021 3:02 pm

Going over notes from all other the place on this project, the feedback has been helpful so far. Another question came to mind:

Reverb coming from the Amp, critical feature - or something you would be ok running from an effect pedal?

I always find reverb pedals allow for more control. That and, I could get some noise down in the amp without the Reverb coming from the amp, but would appreciate some opinions on the matter.

Bob Hoffnar · Post by **Bob Hoffnar** » 28 Jan 2021 6:55 pm

Pretty interesting amp situation ! I would add that you will need two separate speaker cabs in order to avoid phasing issues if you are having two separate signals going through each speaker.

I would look at a vht stereo power amp and a couple channel strips

Or

Two small great sounding amps

Or

Research the recording technique called â€œside chainâ€. There may be a way to get your sound with one small amp.

Or

Go digital. Those new OX from UA and kemper modeling amps are scary good sounding.you can basically design your own signal chain.

Btw: reverb stomp boxes are fantastic these days. Chase bliss just came out with an amazing one.

Iâ€™m into using different gear for different situations. I try not to make compromises for the sake of versatility. Your situation is interesting though. The more I think about it the side chain thing may have something for you.

Mike Schwartzman · Post by **Mike Schwartzman** » 29 Jan 2021 3:10 pm

In focusing on your comment about the TT12 speaker in a 2 X 6V6 amp...I can give a big thumbs up on that because of a different amp than the one I described above. This is a SF Deluxe Reverb from the early 70's.
I was thinking the TT12 might not be a good match for the 22 watt DR, but I gave it a try anyway. I have not gone back since. It's beautiful in that amp despite it's wattage rating, keeping in mind that I was looking for more clean tone.
Reverb...Bob said there are some pretty amazing reverb effects pedals out there these days. I agree. Also, I was very surprised when I swapped the stock tank in the Bandmaster Reverb with the MOD brand tank. Big improvement and only small bucks needed for that upgrade.

Benjamin Davidson · Post by **Benjamin Davidson** » 30 Jan 2021 4:02 pm

I appreciate the feedback.

Bob-
I have any phase issues mitigatex with my isolation device (Gigrig Humdinger, buffered output, a transformer isolated output, and the ability to flip the phase on the isolated signal). I will be building this amp as a head, I run different speakers between my 6 string guitars and my steel with the TT12. I will look into "side chaining" when I have the oppertunity.

I havent found a digital modeling amp that works for me. Kemper sounds great, and very versital. However, having that many options leads to an almost paralisis of possibilities for me that I would need to work through.

I am running a Strymon Bluesky, or a Wampler Ethreal for reverb at the moment, both of which I'm pleased with.

Mike,
That TT-12 is a great speaker, really helped my DRRI.

Bob Hoffnar · Post by **Bob Hoffnar** » 30 Jan 2021 8:46 pm

Ben,
Yea I don't like the modeling amps either but lots of guys do. Side chaining is a super easy concept. Split the signal and run one of the signals into the processing. Hit the processors as hard as needed and totally wet. Then blend the wet signal back into the dry signal. It could be done with a mono amp with two channels or a small 2 mixer.

Earnest Bovine · Post by **Earnest Bovine** » 30 Jan 2021 9:18 pm

anti-gravity paint

Benjamin Davidson · Post by **Benjamin Davidson** » 31 Jan 2021 4:24 pm

Bob-
Looked into side chaining a bit, and looks like a useful tool to fall back on if I show up somewhere with a backline supplied amp to play through.

I'll give it a shot with my Deluxe in the next few days. I run a Stymon Timeline Delay that can kill the dry signal, and run that into the Vibrato channel of the DRRI. It will rejoin the dry signal before the phase inverter. It may not be quite what Im looking for, but it may have its uses.

Bob Hoffnar · Post by **Bob Hoffnar** » 31 Jan 2021 8:42 pm

I would suggest doing your test with the original two amplifiers again using an accurate db meter. Even an unnoticeable volume level difference has a huge effect on tone perception.

J Fletcher · Post by **J Fletcher** » 1 Feb 2021 7:43 am

Have you considered an all tube circuit for the dry signal , and a hybrid , tube pre and class D power section for the wet signal ? Just a thought .

Benjamin Davidson · Post by **Benjamin Davidson** » 2 Feb 2021 2:10 pm

Bob-

I'll be sure to be more thorough with that in the future, I don't have a good db-meter at this time.

Fletcher,

I have considered running a hybrid on the WET side of things, but it would defeat the ability to run true stereo. Not a bad backup plan should my experiments fail.

The amplifier stands at the moment, very Fender Twin-ish... I just have a few key details to continue to dwell over.

1) Power amp section, pair of 6V6s or 6L6s - the discussion of headroom leans toward a set of 6L6s. That would also make Power Transformer selection easier (I could use one spec'd for a Twin). Running a pair of 6V6s would require some guesswork at the PT choice powering 4 6V6s at an appropriate voltage. Nothing that can't be overcome, so either could still succeed.

2) Onboard Reverb Tanks and control circuit on one channel, haven't made up my mind if I need to pursue the classic tube-driven Reverb or if I could live without it.

3) I'm leaning toward building this as a head to 2 different speaker cabs, with multi-tap output transformers. It would be much easier to carry, and I would be able to have my favorite speakers available for both pedal steel and electric guitar.

I appreciate all the feedback on this, its been an interesting project so far.