What is the ultimate bedroom tube amp?

[big_teee]

IME the main thing to quieting Down an Amp is Smaller Speakers.
Example Plug a 50 watt turned down amp into a 10 inch speaker.
Then plug the same amp turned down into a 4x12 Cab.
At the same low level the 4x12 will be much louder probably because of the amount of air moved.
My 50 watt marshall even with 2 Master Vol. is hard to play at a low level into the 4x12 Cab.
It is much more controllable into the single 10 Inch.
So if You are playing in a small apartment do low wattage, and small speakers.
Like a single 8 or 10 inch speaker.
B_T

[Rob55]

I want to build a about a 1 to 0.5watt with one knob. Right now I sit in front of a little Rouge practice amp (totally econo solid state) I found sitting on the curb during bulk trash pickup. (it had a bad input jack.) i use an es clone and it works. I can quietly go from clean to surf to crunch without upsetting the dogs, wife or neighbors with the spin of a few knobs and flip of a switch. I still want a low power amp with one knob in a mahogany combi with a 12" speaker. I know less about amps than I do about guitars and I started doing this recently. Rob

[Chuck H]

How about a Champ type build with a built in attenuator. Attenuating the whopping three to five watts that a Champ puts out isn't nearly as expensive as attenuating a 100W Marshall. Not as bulky either. It could be built right in. I'm usually a proponent for gig worthy amps. But who wouldn't love a mahogany cabinet Champ with a built in attenuator?!?

Kit's available ad nausium. I assume you plan to build your own cabinet?

[Steve A.]

For bedroom levels why not just play your electric guitar unplugged? (Excuse me while I duck to avoid the tomatoes everyone is throwing at me! )
"But I need fuzz, I need distortion, I need my reverb!" IMO if you can't get your guitar to sound good when it is unplugged you are too dependent on electronic devices. Or you have the action set so low that the guitar itself doesn't sing...
I think that most of the guitar heroes of the past 50 years could get some pretty good sounds even when they were unplugged.

That being said I do like a little bit of amplification when I am playing late at night. I don't know if I already mentioned this but the Tech 21 Trademark 10 is a great little non-tube amp that sounds good at low volumes (it has an 8" speaker). If you are going to play at a whisper quiet volume, I don't think that it makes much of a difference if your amp has tubes or not. To get the whole "tube thing" going with the speaker and cabinet you do want some volume. Cranking up your preamp and then cutting the sound level severely with a master volume sounds like a bumblebee in a mason jar...

Steve Ahola

[MWJB]

Well, it's not always about fuzz/distortion/reverb, I find that even if I am playing at a clean volume even just marginally louder than just the acoustic instrument, a quiet, low powered amp (0.25-0.5W) aimed back at my ears just makes it easier to hear what you are doing, rather than having the sound radiate away from you.

[Steve A.]

Well, it's not always about fuzz/distortion/reverb, I find that even if I am playing at a clean volume even just marginally louder than just the acoustic instrument, a quiet, low powered amp (0.25-0.5W) aimed back at my ears just makes it easier to hear what you are doing, rather than having the sound radiate away from you.

I agree completely! I was addressing the 17 year old kids who want the sound of massive stacks but at volumes soft enough to not bother their parents in their bedroom down the hall...

I think that anything larger than a 0.25w to 0.5w amp is going to be throttled down playing at very low volumes- are there any schematics that you would recommend?

We usually want speakers to be as efficient as possible but perhaps they need to design a very inefficient speaker to address the bedroom volume issue. I'd seen ads for a speaker with a dial on the back but I don't remember if that knob adjusted the tone or the volume.

Steve Ahola

[Chuck H]

FluxTone Speakers reduce speaker volume without tone destruction

[Tom Phillips]

First time I heard about FluxTone speakers. Very interesting. Has anyone heard a live demo.
Expensive but unique.

[Chuck H]

This from our own resident member pdf64 on another thread... You know how online reviews go. This one we can trust. There was another thread about the system here too. A lot of poo pooing and pointing out flaws. But of course ALL attenuator systems have flaws. This seems like the best possible attenuation. The only significant flaw I can see is limited speaker availability. I usually use Celestions.

Well, there is another option - a Fluxtone speaker.
I've just bought one and it's pretty damn amazing.
Using it with my AC30 currently and it's incredible to experience the full-on AC30 thing, all that interactive squish and sag that makes a cranked tube amp such a responsive beast, miniaturised down to a level that you can talk over.
I've not used it with the band yet, but turned up full it delivers the goods, even seems to be louder than greenback/blue that are in the vox cab.
I fitted a dual track post phase splitter master volume control to the AC30. I thought that sounded good, but compared to the Fluztone, it just seems flat and sterile, the Fluxtone retains the breath and chime that the MV or resistive attenuators smother.
OK, I just got it, have spent a wodge of money and self delusion may have taken over, but it really does seem to do what it says on the box.
Anyway, gotta go play.
Pete.

[imaradiostar]

I like resistive attenuators. I've made quite a few that are loosely based on Ken Fischer's design and when you're only cutting 4 to 12 dB they're quite usable. That's enough for my 25ish watt 2x7591 amp to get pretty dirty but still be usable in a house of worship, which demands reasonable volumes! The soundman at a club might hate you for playing too loud but at church it's a whole different story! I notice the need for treble moreso than the need for bass so I tend to add "brightness caps" across resistor taps to make the higher attenuation settings brighter.

Anyway, for my resistive attenuators I set them up to match the amp's impedance as close as I can manage- 4, 8, 16, whatever I need to go with the cabinet and amp I'm using. You can always put a resistor in parallel with the whole thing if you need something different. On teeny tiny amps I'll use a low power l-pad (10-15 watt model) but again- at bedroom levels it doesn't really sound like a guitar any more.

I think small push-pull amps (6 to 12 watts) with an attenuator are a better way to go than tiny amps with submini triodes or pentodes as an output section. 6aq5's or 6bq5's seem to retain that "real amp" feel better than triodes.

This all begs another question. What is your ideal amp tone? If I had my choice I'd take at least three amps to every gig- something totally clean and reverby, something voxy and nasty, and something marshally or hiwatt like and dry. Or maybe something with lots of preamp gain and a clean output section. Or maybe something smaller with bias vary trem...nevermind, I want every amp all the time.

In real world gig situations I find that a carefully built low parts count cathode biased amp of between 10 and 25 watts can be loud enough to hang with most bands but quiet enough (with a resisitive attenuator) to work in a quiet venue. I use an assortment of pedals to get various "big amp" sounds as needed. A tube driver rack and an assortment of "marshall sounding" pedals get me most of the tones I need without a huge rig and multiple amps. The amp is usually set slightly dirty. Totally clean tones, in a band setting, are overrated. A little grit and midrange always seems to help the guitar sit better. A push pull amp set at the edge of clean has a way of sweetening clean tones and pedals and making everything sound bigger and more real. I suppose the exception is that totally clean scooped mid fender thing but I still think that sound quickly gets lost in a mix. If that's what you want then more power to you.

/rant

jamie

[Steve A.]

I was thinking of the Eminence FDM speakers, the Reignmaker and the Maverick- both selling for around $175
Guitar World’s Paul Riario reviews the ReignMaker with FDM

It looks like it will give you a 8.5dB cut at maximum attenuation according to the specs:
Sensitivity: 91.5 dB (No knob turn), 100 dB (Full turn)

But it seems like it cuts the sound level more than that in the YouTube video from that page:
Eminence FDM Reignmaker Speaker - YouTube

Steve Ahola

[MWJB]

Hi Steve,

I'm not sure that a low efficiency speaker is typically the answer, with very low signal voltages you want decent sensitivity, otherwise you could end up with dull cleans & and an amp that only works well dirty. I found that when I built my first .5W amp I ended up using a 100db speaker, but I have had good results with 95db speakers, especially with SS rectified versions...in short, the amp will overdrive easily enough, so you probably don't want it limited in clean mode by the speaker.

5F1 & 5F2A schems would be a good starting point, no NFB, possible 2nd stage bypass cap, self split P-P output section. Even running a pair of 6SL/N7 as power tubes is very feasible in a 5D/5E3 style circuit, this opens up OT choices due to better choices in OT primary Z with 2 triodes at each end. E.g. a multitap 8K OT with 4/8/16ohm taps will happily run 6SN7 at matched, or doubled speaker loads. Put an 8ohm, or 16ohm speaker on the 4ohm tap and you can run 6SL7 power tubes. Due to the sensitivity of the power tubes you don't need a whole host of features for flexibilty of sound.

For a tube rectified version aim for 250-260VAC (330-350vdc on the plates, though 6SN7GTA/B & 12BH7 will take 450vdc easily), from each leg of the B+ winding, SS rectification perhaps from 190VAC.

[Rob55]

A champ style with an attenuator. I like the concept, I think, being as I don't even know what an attenuator is. What is the difference between an attenuator and a master volume? Why do some write about master volume like it is a bad word?

Were would I find a schematic of an attenuator, or master volume on a champ type.

I have nothing against gig worthy amps for gig worthy players. I do not qualify. I do occasionally strum chords with a couple of friends who play well and enthusiastically. They jam. I do something else. For some reason they want me to "turn it up."

I frequently play without the amp. My wife enjoys that. Sitting in front of the amp helps me hear mistakes, sustain and the how the infrequent hammer on or bent note I throw in sounds. Sometimes, when she leaves, I'll put CCR on the stereo and turn up the amp.

I've found a 5f1 kit at tube depot. I have not found a 5c1 kit. I don't really know the difference. I won an old amp off ebay about the same time I discovered the 5f1 kit.

thanks for the feed back.

Merry Christmas
Rob

[Tubenit]

SoLow Watt

I've built an amp using a 5879 V1, 12A_7, into the triodes of an ECL84, into the pentodes of the same ECL84's.

So only 4 tubes are used along with an inexpensive Hammond PT.

It's about 4-5 watts and has a PPIMV. I like the tone of it alot.

With respect, Tubenit

[Steve A.]

A champ style with an attenuator. I like the concept, I think, being as I don't even know what an attenuator is. What is the difference between an attenuator and a master volume? Why do some write about master volume like it is a bad word?

Usually an attenuator would go between the output of the amp and the speaker (stereos used L-pads for this). With a master volume you lose power amp distortion which is fine for a modern amp which depends mainly on distortion in the preamp; with a vintage low gain amp (like the Champ) most people want the power amp distortion.

HTH

Steve Ahola