Hi guys I have one of these pre made tube amps with a cd and a phono input. It’s only 2.5 watts and is pretty small Things I’d like to change is this Add some type of tone or eq controls Add a preamp outputs so I can use it as a preamp or add output/ input rca’s so I use a eq with it Here’s from photos of it and I’ll try to remove the cover for pics of the inside And for power it has a wallwort power supply
Thanks
Thanks
Your parade has been rained on, sorry. The wherewithall to do what you want is not present.
Truly good tone controls are complicated. You are not going to be able to add 4 tubes to that unit. A tube/FET hybrid variation on that theme still needs 2 additional "bottles".
My guess for the tube complement of the unit in question is a 12AX7 and a 6BM8, in each channel, with the 'X7 being a phono preamp. The 'X7 triode has very poor load driving ability and will misbehave if connected to low I/P impedance SS device, like an equalizer.
The best suggestion I can come up with is to use the headphone O/P to drive an equalizer and have the equalizer drive a separate power amp.
Truly good tone controls are complicated. You are not going to be able to add 4 tubes to that unit. A tube/FET hybrid variation on that theme still needs 2 additional "bottles".
My guess for the tube complement of the unit in question is a 12AX7 and a 6BM8, in each channel, with the 'X7 being a phono preamp. The 'X7 triode has very poor load driving ability and will misbehave if connected to low I/P impedance SS device, like an equalizer.
The best suggestion I can come up with is to use the headphone O/P to drive an equalizer and have the equalizer drive a separate power amp.
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Well any type would help. It’s pretty flat one the highs and lows. I know not much can be done with the bass with the type of tubes it uses
So there's a thing called aural compensation - pretty much a boost on both highs and lows at _lower_ listening levels. Such that when you listen at a lower volume level, the bass and treble dont go dropping off - which is a normal and natural characteristic of human hearing.
You can get a cheap Chinese implementation of a volume control that does this on ebay.
Japan AIKO 100K Equal Loudness Volume Control Dual Potentiometer Adapter Board 783710087898 | eBay
It just drops in place of your existing volume pot. You'll need to solder, of course and may have knob issues, as who knows how close this is to the existing control's knob connection. For <$8 shipping included, it's worth a shot / listen.
I got one and it's a better control than what was in the amp. I figure I can add a switch into the two wires going to the pot taps, to switch out the effect if I ever need to. Right now, I simply turn down the volume on the device feeding the amp - and turn the amp all the way up - that eliminates the tone compensation. I can otherwise play with where I have this aural compensated volume control set and the signal level feeding it to dial in a response I like. Note: it cant do bass down / treble up - or - bass up / treble down - the so called "tilt" control. There's something else you can buy if you want to do that.
with luck,
You can get a cheap Chinese implementation of a volume control that does this on ebay.
Japan AIKO 100K Equal Loudness Volume Control Dual Potentiometer Adapter Board 783710087898 | eBay
It just drops in place of your existing volume pot. You'll need to solder, of course and may have knob issues, as who knows how close this is to the existing control's knob connection. For <$8 shipping included, it's worth a shot / listen.
I got one and it's a better control than what was in the amp. I figure I can add a switch into the two wires going to the pot taps, to switch out the effect if I ever need to. Right now, I simply turn down the volume on the device feeding the amp - and turn the amp all the way up - that eliminates the tone compensation. I can otherwise play with where I have this aural compensated volume control set and the signal level feeding it to dial in a response I like. Note: it cant do bass down / treble up - or - bass up / treble down - the so called "tilt" control. There's something else you can buy if you want to do that.
with luck,
So your saying to replace the one that’s in it with the one your showing and it will help with the lack of highs and lows?
I can bread board it in for testing
Thanks
I can bread board it in for testing
Thanks
I sent an offer of $6 for two of them Thanks. And any pics you may have of your install,if any, would be great I’ll report my findings after I setup a test board for it before in do a permanent install if the sound is better I only use this amp with some of my Klipsch speakers. KG4 or H1’s and KI102’s These are all very deficient Speakers so I probably only use about 1 1/2 Watts of the amps 2.5 watts. I need to look up and see what other tubes will work in it and see how the sound will change as well Thanks guys for all of your positive information
if you use tubes, use a 6922 or equivalent that can drive the circuit without buffering. then it will be one tube per channel.
I used 6922 as preamp before volume / balance and 6922 to drive tone controls feeding SS amplifier. > 110db s/n
I used 6922 as preamp before volume / balance and 6922 to drive tone controls feeding SS amplifier. > 110db s/n
You said deficient and I think you meant efficient, though I understood what you're saying.
When I was a young man, my teenage friend's friend had a dad with K-horns driven by McIntosh tube equipment. We were visiting and I asked if I could touch. The preamp had a separate rotary control for this effect, labeled "aural compensation". We weren't playing the system very loud. I turned that control clockwise and it was like magic. Oh, to have 18 year old ears again with Mac stuff and big 'ol K-horns!
I guarantee I had no idea at the time just what I had my hands on, nor what that control did. All I knew was then it started sounding really good. What I really want is that control and there's a couple designs to choose from. The ebay control is a step to getting there and the amp needed a new volume pot anyway.
I'll see if I can scare up a picture of the install and post a reply here
When I was a young man, my teenage friend's friend had a dad with K-horns driven by McIntosh tube equipment. We were visiting and I asked if I could touch. The preamp had a separate rotary control for this effect, labeled "aural compensation". We weren't playing the system very loud. I turned that control clockwise and it was like magic. Oh, to have 18 year old ears again with Mac stuff and big 'ol K-horns!
I guarantee I had no idea at the time just what I had my hands on, nor what that control did. All I knew was then it started sounding really good. What I really want is that control and there's a couple designs to choose from. The ebay control is a step to getting there and the amp needed a new volume pot anyway.
I'll see if I can scare up a picture of the install and post a reply here
I have no experience with this but the brand seems to get a lot of positive comments. This is considerably more expensive than the eBay loudness control linked earlier but it is also a lot more versatile.
Schiit Audio, Headphone amps and DACs made in USA.
Schiit Audio, Headphone amps and DACs made in USA.
Here how look like inside your amp, if I have this amp I will never ever try to made any modification to the original design. How you can see lots of solid state component, a dc-dc boost converter also the phono riaa pre-amp is solid state one, so the warmth of a pure tube amp is compromised and even the volume pot look quite accessible still could be difficult add any circuit to it, the only thing you can do is add and external tone control between the source and the rca input, can be a solid state one or a tube based one, I already made some of them and one in particular 3 tone control work like a charm, here picture of it, you can find schematics and suggestion in this website Practical Tone Controls.
All the best
All the best
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I'm too busy to build outboard tone controls right now, so bought one of these and it is very quiet, has plenty of boost/cut, is very small, and wasn't that expensive, especially in comparison to my preamp and amp. Definitely pleased with the unit.
That looks nice and sure it would work great. But I would need two. One for my cd input and one for my phono input
Even with one the cost is high for me
Even with one the cost is high for me
Schiit Loki Tone Control
I own a Loki. It's really a fine way to go. Very transparent. I have tried minidsp. Very flexible but the transparency is not acceptable to me.
Schiit has a return policy, so you an try it and see if it does what you need. For $150 you cannot go wrong.
I own a Loki. It's really a fine way to go. Very transparent. I have tried minidsp. Very flexible but the transparency is not acceptable to me.
Schiit has a return policy, so you an try it and see if it does what you need. For $150 you cannot go wrong.
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