Can we use resistor attenuator

[kldguitar]

I read book about THD hot plat, It said Hot plat is a purely resistive attenuator, with some passive LC frequency shaping to compensate for the perceived loss in bass and treble as the attenuation is increased.
I think we can use purely resistive attenuator and EQ in amp, Because EQ in smaller signal easy and lower cost, when we use EQ in attenuator, It is very expensive because we have to use high voltage and current LC components.
It will high cost of all gear.

[R.G.]

I read book about THD hot plat, It said Hot plat is a purely resistive attenuator, with some passive LC frequency shaping to compensate for the perceived loss in bass and treble as the attenuation is increased.
I think we can use purely resistive attenuator and EQ in amp, Because EQ in smaller signal easy and lower cost, when we use EQ in attenuator, It is very expensive because we have to use high voltage and current LC components.
It will high cost of all gear.

Back to asking us what to do so you can put it into your commercial products again, eh?

Well, in that case, sure. You don't need any stupid old frequency shaping. A simple resistor attenuator is even BETTER than that frequency shaped stuff. Much better. You want absolutely flat frequency response from your guitar amps if you can get it.

Much cheaper too.

Good luck with it.

[Chuck H]

Oh R.G.

KLD did actually man up a helpful post to a thread about a month ago. I gave him kudos for doing it too. But your right that it's pretty much a one sided thing. But he is just a guy trying to build amps for $$$ like many others that post here.

KLD,

FWIW... There are a couple of purely resistive attenuators on the market that are well accepted by players. Perhaps look into that and copy one of those for your built in attenuator, I'm not mentioning names, a little research and you'll figure it out.

Attenuators are usually used when power tube distortion is wanted. So EQing the amp doesn't really work because it's pre-distortion and usually changes the clipped signal in a bad way. One tip I will give, The purely resistive attenuators that players seem to prefere use a higher impedance load than the amp setting to get closer to the average load presented by a real speaker.

Now, I should get a "thanks" for my very useful post. Also, take the time to help other posters once in a while. Otherwise I'm putting you back on the troll bus.

Chuck

[R.G.]

Oh R.G.
KLD did actually man up a helpful post to a thread about a month ago. I gave him kudos for doing it too. But your right that it's pretty much a one sided thing.

Oops. Sorry. I missed that one post.

[trevorus]

Hey, all these things are a compromise. Never will a reisitve attenuator sound exactly the same as without. Do a little experimentation. Draw up some plans, try it out, and see what works. Then you have that eureka moment where you discover something. It's very rewarding.

[imaradiostar]

I find a little hotplate goes a long way- I usually kill between 4 and 12 dB depending on the gig.

You may find that a resistive attenuator will sound great and needs only a mild treble boost in the higher cut settings to sound usable. You will find that some amps sound best when working hard but not heavily distorting- this, I feel, is the ideal range for a hotplate or airbrake. The amp is still adjustable but it's working hard enough that the power tubes become a bigger part of the sound.

If you take apart a hotplate you'll find two interesting quotes inside; this is the best I can remember it:

"If you can read this you've voided your warranty."

“Women and cats will do as they please, and men and dogs should relax and get used to the idea.” -Robert A. Heinlein

I always tend to have a look inside gear after I buy it- I feel I've earned the right to do so. This doesn't mean I copy it, but it usually satisfies the tech nerd in me. Finding those two quotes was especially awesome. It made me really appreciate THD and Andy Marshall. Not to mention I love Heinlein!

jamie

[Regis]

First, get a toaster. Hook your input jack to one end of the coil, the output to the other end, the connect it to a high powered guitar amp.

Or, get a good heavy duty blanket. Crank your map, cover the amp with the blanket, and revel in the attenuation it delivers.

Or, design an attenuator yourself, instead of trying to rip off American ingenuity, you Chinese commie bastard.

[unparalleled]

Whoops!
If I posted something like that the New Zealand Nanny State Government department would have their Race Relations man knocking on my door within hours, and I would be on National TV news!
(The man with that job is usually an immigrant from India or somewhere with a large axe to grind.)

Mind you, this guy is cheeky.

[Chuck H]

Whoa!!! Regis... Don't hold back, man. Tell us how you really feel.

Cheeky doesn't touch it. If you search this guy (kldguitar) you'll see that he;s trying to gleen any hip knowledge he can to sell overseas contracted gear. He gives nothing back and NEVER follows up. I wonder why he even continues to ask questions here. If you don't follow up on discussions and participate in the "community" you never gain any understanding. One look at the web site tells all. A bit off the mark and not willing to go the distance to get there. But really, there ARE plenty of guys who design and then contract cheap foreign labor. Some even participate here. So what makes kldguitars different is that he's a social retard who can't understand that this is a forum made of people, not strictly a profit resource.

I read him real good once and he actually fired back with some passion. He deleted it the next day realizing it wasn't conducive to his cause. Even though we were both being a$$ho!e$. Like many of us he's just small time. Trying to make some $$$ and build some amps. He would do well to make some friends here, and I try sometimes to give him the chance, but I don't think he has the social skills. It's sad really. But I digress. He's not really a cause worth pursuing. He'll probably never read this. Instead he's stewing somewhere about why it's not working out. The next time we hear from him he'll be asking another pedantic Q and hoping for instant enlightenment again.

He's not a bad man (evil commie, Chinese puppy mill owner, etc.) but he is an annoying goof ball.

Chuck

[J M Fahey]

Well, your government should take China very seriously.
To them it is not the Far East but the Uncomfortably Close North.

[d95err]

Never will a reisitve attenuator sound exactly the same as without.

If it did sound the same, it wouldn't be attenuated, now would it?

Attenuators are not supposed to sound the same, they are supposed to sound less loud. It is completely irrelevant to compare the attenuated sound with the un-attenuated sound.

The relevant comparison is to start with the dB level you need to play at and compare different ways to get there. For example:

• The amp with an attenuator
• The amp with volume turned down low enough
• The amp with a much less efficient speaker
• The amp with at low volume with a fuzz/OD/dist pedal
• The amp with a dummy load, DI box, amplified through the PA or an active monitor

[trevorus]

If it did sound the same, it wouldn't be attenuated, now would it?

Attenuators are not supposed to sound the same, they are supposed to sound less loud. It is completely irrelevant to compare the attenuated sound with the un-attenuated sound.

The relevant comparison is to start with the dB level you need to play at and compare different ways to get there. For example:

• The amp with an attenuator
• The amp with volume turned down low enough
• The amp with a much less efficient speaker
• The amp with at low volume with a fuzz/OD/dist pedal
• The amp with a dummy load, DI box, amplified through the PA or an active monitor

That's kind of what I was driving at. Attenuate to a less loud sound, with a nearly identical tonality. That is a very tough goal, because of all the variables involved, some of which you listed.

[mooreamps]

I read book about THD hot plat, It said Hot plat is a purely resistive attenuator, with some passive LC frequency shaping to compensate for the perceived loss in bass and treble as the attenuation is increased.
I think we can use purely resistive attenuator and EQ in amp, Because EQ in smaller signal easy and lower cost, when we use EQ in attenuator, It is very expensive because we have to use high voltage and current LC components.
It will high cost of all gear.

I guess the answer is you can use anything you want. But what you won't do, is use my electronic power brake since I have never released it into the public domain. Also, now that I have a working circuit for electronic volume control, it's doubtful I would release that either ; since from what I am gathering you would just copy my design work and keep it for your own singular ends.


-g

[888guitars]

I think Webber has the best Idea using an actual driver in the circuit to help with the electromotive force. Its hard to simulate a speaker.

[unparalleled]

I think Webber has the best Idea using an actual driver in the circuit to help with the electromotive force. Its hard to simulate a speaker.

I am thinking of trying a compression driver with an adjustable needle valve or a regulator valve screwed onto it instead of a horn.
Or maybe a closed chamber of variable air volume to load the speaker driver.