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我斗胆答题：应该是在不同音量下，都让后级管处于相同工作点吧，这样可以得到更饱满的声音。。。。也可以在小音量下得到后级管的饱和失真（也许还包括输出变压器的饱和失真？） 请问LZ 晶体管音量是不是比电子管音量差一大截的············我的80W的晶体管后级可以开到一半多 150W的三整流开到十分之二就感觉音量大很多了······
[ 本帖最后由 哭泣的电吉他 于 2012-7-10 03:22 编辑 ] 来个轻松话题，一个美国设计师的小手工。 哈哈， 原帖由 jumping_pro 于 2012-7-9 23:57 发表
为什么不采用master 而是用衰减回路？
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我斗胆答题：应该是在不同音量下，都让后级管处于相同工作点吧，这样可以得到更饱满的声音。。。。也可以在小音量下得到后级管的饱和失真（也许还 ...
非常接近设计的初衷，实际上，我们过往对衰减器有一些不是很正确的看法，认为他主要是保存后级失真，这个在大功率功放上没错。但是，在小功率功放情况下，如何保证前级失真能不失真的被后级放大，这就是设计者高明的地方了。 好文章 幫推 我正想给我的100瓦全管配一个衰减器，请问有什么牌子比较好，不是很懂！我箱子买回来都没试过开大音量，很想配个不错的衰减，请大家推荐下我！！先谢谢。。。。。 原帖由 haohaohaohao 于 2012-7-16 02:47 发表
我正想给我的100瓦全管配一个衰减器，请问有什么牌子比较好，不是很懂！我箱子买回来都没试过开大音量，很想配个不错的衰减，请大家推荐下我！！先谢谢。。。。。
买贵的？还是买对的？ 我想知道，给ORANGE OR15用的衰减器，DR Z和这个比，究竟哪个更好，音色损失更少？
我总觉得DR Z那个是骗钱的。而且特吃音。
回复 90楼 豆子传说 的帖子
我们有三种衰减器，按设计思路分两种， AT50,AT100是一类(http://item.taobao.com/item.htm?id=6749697322,)(http://item.taobao.com/item.htm?id=8637156948)
PB1(http://item.taobao.com/item.htm?id=14966630858) 是一类
AT 系列要求严格阻抗匹配。 PB1 系列不要求阻抗匹配。
如果要我推荐， 15瓦的小箱， AT50 就可以，功能够用，同时有自补偿功能。价格也比较合适。 关于吃音问题，我这里多说两句。
我们前面已经探讨过外挂式的衰减器分为：感性耗能式，和阻性耗能式两种。 相比感性耗能式的大电感来说，阻性耗能式要安全，对音色的影响也更小一些，所以使用更广泛一些。
但不论那种，都要考虑听力补偿的问题，由于我们的听力，音量和响度不是线性关系，人的听觉在不同音量下对不同频率的反应不同，当一个100瓦的功放衰减到30瓦，尽管在物理曲线上，可能声音没有变化，但听上去会觉得少了一些声音，这个不同的人反应也不太一样。
这就是吃音的问题。
一方面衰减器要考虑补偿问题，另一方面，也要对功放EQ进行相应调整，不是说接上衰减器就万事大吉，其他地方一点不动，这是一个误区。
另外，衰减的范围也是有一定的限制，一个100瓦的功放衰减到1瓦，甚至推一个扬声器都很困难了，很难要求音色不变；但一个50瓦以下的功放衰减到1瓦后，音色保持不变就比较容易作到，这就是说，再买机器时，你最好选对功率。如果你是练习或是小范围（100-200人空间） 演出，50瓦以下功放就够了（可以参看上面的文章），再大的声音可以用PA来完成。 我个人在家是用15W的HEAD的，但是在外面是用100W的HEAD的。但是有时候又想在家用100W的MARSHALL，所以很纠结。我觉得还是买个PB1的好。
我就是想比较一下它和DR Z还有THD POWER PLATE的吃音多少的问题，毕竟它的价格很便宜。里面是不是也是珐琅电阻？ 原帖由 豆子传说 于 2012-7-18 17:24 发表
我个人在家是用15W的HEAD的，但是在外面是用100W的HEAD的。但是有时候又想在家用100W的MARSHALL，所以很纠结。我觉得还是买个PB1的好。
我就是想比较一下它和DR Z还有THD POWER PLATE的吃音多少的问题，毕竟它的价格 ...
PB1 用的是珐琅电阻，实际上，衰减器是搭棚纯手工，国外的人工，进口税加在一起，不贵也难。你用过Dr.z和 THD 是很好一种体验。可以比较一下。
一篇关于如何使用衰减器的好文
Gain,Distortion, and Other MysteriesI decided todevote a full page to this subject rather than include it in the FAQ page. Weget emails and phone calls every day asking for power tubes that will get moregain in both single channel amps and multiple channel amps.
So let's open this can "O" worms! I thoughtit best to quote some of the questions we get here everyday and give simpleanswers. So here are a few of the most common questions and their answers.
#1.
"I just have to have a lot more power tube distortion frommy amp at much lower volume levels! What tubes do I need?"
Answer:
In 99.9% of all guitar amps powertubes will not get you more distortion at lower volume levels. An amp designedto make 100 watts using a quad of 6L6's will make right at 100 watts with justabout any 6L6. Even if you use some of the lower power 6L6's like the GT GE'sand you drop the power down to about 90 watts you will not lower the decibellevel by anymore than a fraction of one decibel which is barelyperceivable.In most 100 watts amps you can pull either the inside twotubes or the outside two tubes to run in half power.
#2.
"Willrunning my 100 watt amp with two power tubes make it half as loud?"
Answer:
No. It will only drop the soundpressure level by three decibels. If you have ever plugged into a 50 watt halfstack and then compared it to a 100 watt half stack then you know what I mean.The 100 watter has a little more grunt but the 50 watter is not far behind. Inturn, players running 50 watters and looking for more power are oftendisappointed that a 100 watter is not twice as loud. This is simply becauseevery time you double your power you only get three decibels louder. So youplayers looking for a bedroom amp need to look for amps that are between one tofive watts.
#3.
"Which power tubes in my amp are for the lead channel?"
Answer:
All of them! This is one of the mostmisunderstood things about multiple channel amps. I can't tell you how manyplayers ask this question and believe that their power tubes or some of themare used specifically for the lead, gain or drive channels in their amp. In99.9% of all guitar amps the distortion and gain comes from the front end ofthe amp by overdriving the preamp tubes. So in amps like Marshall's, Peavey's,Mesa's, Laney's, Engl's, Bogner's, Traynor's and Fender's when the amp is inthe drive channel and you are playing at
anythingbut
very high volumes youare getting no power tube distortion what so ever. If you want to experiencepower tube distortion then turn the master volume up all the way, switch to theclean channel and then start cranking the channel volume up. On most amps whenyou get to about 5 or 6 you will be getting a little power tube, preamp tubeand speaker distortion. This is commonly known as "the sweet spot"and in 50 to 100 watt amps this will be quite loud. So if your pant legs arenot blowin in the wind, your not there yet!
#4.
"What is gain?"
Answer:
Gain equates to, and is volume. Inolder amps there was volume or gain meaning exactly the same thing. When mastervolume amps entered the scene in the early 70's then the word "gain"gathered a new definition meaning distortion. In modern amps distortion is referred to as gain which is a product ofoverdriving and / or cascading the signal from your guitar thru several preamptubes to compound the gain.
#5.
"Can I get high gain powertubes?"
Answer:
The short answer is no. This is atough one to explain so I'll start from the beginning. When tubes are born(it's a beautiful thing!) they all draw different amounts of natural platecurrent which is why they need to be matched for amps using multiple powertubes. Cold tubes are paired up with cold tubes just as hot tubes are pairedwith hot tubes. Some tube resellers grade tubes very loosely into three colorgrades. This is VERY inaccurate to say the least. Other resellers offer up to10 grades which is more accurate. At Eurotubes we have between 25 to 30different grades of all types of power tubes. If your amp is a fixed non-adjustable bias amp like allMesa's, some Peavey's, the new Traynor's and some Fender's then choosing theproper grade for the power tubes is VERY important because depending on wherethe bias is fixed, colder tubes will lower the bias where hotter tubes willraise the bias. This is why we spend a LOT of time here at Eurotubes testingand documenting what grades will get the bias in fixed bias amps as close aspossible to where it should be to accommodate different playing styles.
Now back to that "Can I get highgain power tubes?" question. (Told you this was a tough one) There is anacceptable window of bias in any amp and keeping the bias cooler at between 60%to 70% of max dissipation will get a good warm tone and your power tubes willbreakup or distort a little later. Leaning on them harder and getting the biasup to 80% to 90% dissipation will cause you power tubes to brown out slightlyand breakup or distort a little earlier. The difference between 70% and 90% isvery noticeable but the difference in where you will get power tube distortionis not a night and day difference. If your amp will breakup at 6 on the cleanchannel with the tubes biased at 70% then on average it will start to breakupat about 5 with the tubes biased at 90% and tube life will decrease by about20% to 25% (Ah, the cost of tone!).
So in a fixed bias amp the grade ofthe tube is very important to get the desired results. In an adjustable biasamp the grade is MUCH less important because it's where you set the bias thatcounts.
#6.
"How can I get power tubedistortion at low volumes?"
Answer:
There are two answers to this one. #1would be to use a much smaller amp that can be turned up all the way. #2 wouldbe to use an attenuator. These are referred to as Hot Plates and Power Brakesand are available from lots of different manufacturers including THD, Marshall,Alessandro, Dr Z and of course Weber. The Weber attenuators are unique becausethey actually use a speaker motor and these are also one of the mosteconomical.
#7.
"I bought an attenuator and nowI don't have a clean channel, what happened to it?"
Answer:
Believe it or not, this is a VERYcommon question. A player will buy an attenuator, wire it up to his multichannel amp, switch to his drive channel, dime out the amp, attenuate down to avery low volume level and experience massive power tube and preamp tubedistortion. In most cases a big smile will ensue and all is well! (PictureSnoopy dancing in the fields) At some point the player decides to switch to theclean channel and quickly finds that it's gone?!?! Well of course it's gone!The amp is playing at full volume so you will get power tube distortion nomatter what channel you are in.
Attenuators were originally designedhelp players get to that "sweet spot" where you were just gettinginto preamp and power tube distortion which most of the time is too loud. Yousimply crank the amp up to where you like it and then attenuate down 2, 4 or8db until you blended into the stage mix.
#8.
"I like my attenuator but itjust doesn't sound the same as when the amp is cranked up by it's self, why isthis?"
Answer:
Correct! An attenuator can onlysimulate two out of the four components that are involved when you crank up anamp. The four components are #1 preamp tube distortion, #2 power tubedistortion, #3 speaker distortion and #4 the physical movement of air that yourspeakers produce at high volumes. So the two components missing are speakerdistortion and the physical movement of air and these are VERY BIG components!Some attenuators have built in EQ to help modify the tone but if you arelooking to get the exact tone and feel of your amp at higher volumes, you can'tget all the way there from here...
Think about your car stereo and howthe loudness button works, when you turn down the volume you loose that fullsound and there is no punch to the music, the manufacturers know this so forlower volumes they give you the "loudness" button which miraculouslybrings back the fullness of the music by boosting the low frequencies. Anattenuator drops your volume but does not discriminate when it comes tofrequencies and has no loudness button. Ted Weber took his Mass Lite units astep further incorporating dual controls for Low/Mid and Mid/High. This helpsquite a bit but if you want to get more of a full sound at lower volumes youwill need to run parametric or at least a ten band EQ to get anywhere close andyou will find a lot missing in the 60 to 140 cycle range.
The harder you work a speaker thebetter it sounds until you reach the point where the voice coil is out oftravel so players using a 4/12 cab will find that when attenuated down to a lowvolume their sound will be particularly thin. If you want a better sound atlower volumes try running a single 12 where you can work the speaker a little,this will make a lot of difference over using four speakers that are barelyworking.
#9.
"I like my attenuator but when Idig in the amp just doesn't respond like it does without the attenuator, why isthis?"
Answer:
Correct again! This is because an ampthat is dimed out is out of headroom. Headroom refers to how much power the amphas left to hit peaks. If you turn the amp up to say half way and play with amoderate attack and then really dig into a note or slam a chord you will hear avolume difference because your amp has the reserve power or headroom to respondto your increased dynamic. When you're playing thru an attenuator and the ampsis dimed out then there is no reserve power or headroom to respond when you diginto a note. The amp is compressed and flattened out.
#10.
"My wife says my amp is stilltoo loud, what do I do?"
Answer:
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#11.
"Why do I loose definition athigher gain settings?"
Answer:
Ah yes, definition versus distortion.Most of the time I get this question from good players who have practiced anddeveloped good playing technique. This is NOT to say that players who have notbeen at it for long can't hear this and I'm sure my answer will stircontroversy but here goes! There are two basic camps here, #1 players who havea good precise technique who want to hear every little string nuance and wantto play with lots of gain, ala early Eddie VH or Petrucci or Satch. #2 playerswho like a lack of definition simply because its easier to sound like a shredmaster even if the technique is sloppy.
Now here comes the controversialopinion part of this answer. I like to hear definition and love to hear a goodplayer shred away and this is one of the main reasons I always liked the olderEuropean tubes and was drawn to the JJ Electronic tubes when I played and heardthem. In my opinion the russian and chinese tubes lack definition and"fuzz up" when saturated. This "fuzz" is what a lot ofplayers refer to as distortion. We hand pick a lot of high gain preamp tubesfor our customers who want and need lots of gain but also want the definitionand the JJ ECC83S's deliver. If you want or like the "fuzz" then seekout the russian and chinese tubes.
#12.
"I saw this thing on ebay calledthe "Suck Knob" does it work?"
Answer:
Yes, it works but in general, itsucks... It does not do what an attenuator does, and if you have read the restof this page then you know what limitations attenuators have, if you have notread it I recommend it. The suck knob simply allows you to lower the signalfrom the front end, or preamp section of your amp that feeds the back end, orpower section of your amp. It does NOT let you get power tube distortion atlower volumes, so the sound you get is all front end distortion and no powertube distortion, I repeat NO power tube distortion! So if you want power tubedistortion at lower volumes, then only an attenuator will do this. However, ifyou simply want more preamp tube distortion at lower volumes then by all means,go for the "suck Knob", then you too can suck! 原帖由 kldguitar 于 2012-7-31 09:02 发表
Gain,Distortion, and Other Mysteries
I decided todevote a full page to this subject rather than include it in the FAQ page. Weget emails and phone calls every day asking for power tubes that will get ...
这一段比较重要，基本回答了所有关于衰减器的问题。
作者列出四个要素： 1.前级失真2，后级失真3.扬声器失真4.高音量下的扬声器空气运动。我们实际在选用衰减器时，认为一个好的衰减器可以适用于所有的功放和喇叭。实际情况却不是这样，不同的喇叭，特性不同，输入不同功率，声学表现也不同，一种衰减器不能适用于一切功放，这就是同一款衰减器有人说好，有人说不好的原因。
对于喇叭箱来说，4x12 喇叭箱衰减后的音质就没有1x12喇叭箱同样衰减后的音质好。这是过去大家不注意的地方。
Correct! An attenuator can onlysimulate two out of the four components that are involved when you crank up anamp. The four components are #1 preamp tube distortion, #2 power tubedistortion, #3 speaker distortion and #4 the physical movement of air that yourspeakers produce at high volumes. So the two components missing are speaker distortion and the physical movement of air and these are VERY BIG components!Some attenuators have built in EQ to help modify the tone but if you are looking to get the exact tone and feel of your amp at higher volumes, you can't get all the way there from here...
Think about your car stereo and howthe loudness button works, when you turn down the volume you loose that fullsound and there is no punch to the music, the manufacturers know this so forlower volumes they give you the "loudness" button which miraculouslybrings back the fullness of the music by boosting the low frequencies. Anattenuator drops your volume but does not discriminate when it comes tofrequencies and has no loudness button. Ted Weber took his Mass Lite units astep further incorporating dual controls for Low/Mid and Mid/High. This helpsquite a bit but if you want to get more of a full sound at lower volumes youwill need to run parametric or at least a ten band EQ to get anywhere close andyou will find a lot missing in the 60 to 140 cycle range.
The harder you work a speaker the better it sounds until you reach the point where the voice coil is out of travel so players using a 4/12 cab will find that when attenuated down to a low volume their sound will be particularly thin. If you want a better sound atlower volumes try running a single 12 where you can work the speaker a little,this will make a lot of difference over using four speakers that are barelyworking. 我很喜欢AT100的补偿和耳机模式。挺好。壳子可以买回去自己彩绘 原帖由 豆子传说 于 2012-8-23 20:10 发表
我很喜欢AT100的补偿和耳机模式。挺好。壳子可以买回去自己彩绘
你真有才，很可惜你没有买到最后一台AT100, 改型后的AT100可能旧没有空间让你彩绘了。 不错，虽然现在看来还是有点费解... 很不错，就是有些内容一时不容易理解，得慢慢消化。 原帖由 豆子传说 于 2012-7-18 17:24 发表
我个人在家是用15W的HEAD的，但是在外面是用100W的HEAD的。但是有时候又想在家用100W的MARSHALL，所以很纠结。我觉得还是买个PB1的好。
我就是想比较一下它和DR Z还有THD POWER PLATE的吃音多少的问题，毕竟它的价格 ...
比较了吗？ 感觉如何？ 好帖子啊！ 原帖由 wulong_shen 于 2012-9-17 13:09 发表
好帖子啊！
所以看得人少 没事看看 How Many GuitarAmp Watts Do You REALLY Need?This is how I help customers decide onhow much power they really need. Bascially, we determine together how muchclean headroom is required and select the amp on that basis.Headroom is defined as being the volumeat which the amp starts to overdrive or distort the incoming signal from yourguitar. Fender Twins are known for producing LOUD clean tones – it’s extremelydifficult to get that amp to overdrive. Therefore, it has LOTS of clean headroom.A 1 watt amp designed to produceoverdriven and distorted tones (basically more of a distortion pedal than anamp!) will overdrive at very low volume. This type of amp has very low cleanheadroom.So, how do we figure out how much cleanheadroom and output power is required?1.
Determine thesyle of music. There are two extremes that relate power to music style to cleanheadroom. AC/DC cover band? Crunch all night with extra distortion for solos.Country band? Predominantly clean all night. The cleans have to be loud enoughto keep up with your band’s stage volume.2.
Determine how toget distortion for solos. Are you going to rely on your amp for distortion or areyou going to set up your amp for cleans and use pedals?3.
Determine thevenues where the amp will be played. Do you only play at home? Do youoccasionally jam with another guitarist or two? In a garage/basement band? Gigin small venues only? Large rooms? Stadiums? The jump from playing by yourselfor with another guitarist to playing in a band is step that may require moreclean headroom regardless of music style and method of generating distortion.The jump from a band setting in a small venue (basement, small bar) to a largervenue (bigger bar, halls, etc.) may require another increase in clean headroom.The key is to determine when/if your amp will be mid’ed and your band’s stagevolume.The louder you need clean tones the moreheadroom you need and the more power you require.Playing music that requires lots ofclean tones and you have to be loud enough to keep up with the band on stage?You need more headroom.Do you rely on pedals for overdrive anddistortion and your amp to be clean all the time? You need more headroom.Do you want your amp to produceoverdrive and distortion and loud cleans are not as important? You don’t needas much headroom – you want the amp to overdrive at lower volumes. You need todrive the amp into its sweet spot at a volume level that won’t make the first 5rows of the audience look like those guys riding rocket sleds.Now, not all amps are designed the same.Some amps of equal power are specifically designed with more or less headroom.It’s rare to get the opportunity to play an amp in your chosen venue beforebuying – whether you buy online or from a local store (ever tried to determinean amp’s clean headroom when the kid next to you is practicing tapping usingthat 100 watt Marshall?) – so you need to rely on knowledgeable players and themanufacturer to guide you. It also helps to have an unconditional, money-backguarantee so that you can get ALL your money back if for whatever reason itturns out that the amp you bought is not suitable.How Much GuitarAmp Power Is Enough?Getting back to where we started, why doI think that 50 watts is all that would ever be required?Becauseregardless of the clean headroom required, youshould never be in a position where stage volume demands more power than 50watts. A 50 watt amp turned up enough to get it into its sweet spot isPUNISHINGLY loud.So, before you assume you need 100 wattsbecause that’s what ___ uses, think about the music you play, how you get youroverdriven/distorted tones and where you play. Then carefully consider how muchpower you REALLY need! 根据功率和功能不同， KLDguitar 的四个型号衰减器价格从400多到1000以内。目前，我们正在考虑的是一款功能很强的AT100 升级版
100瓦， 内置 RED BOX 和Dummy load, 外接DI, headphone. 实现静音录音， 特别首创 speaker distortion 模拟调节。
这样，在衰减器方面，KLDguitar 全产品线覆盖了从单一功能到衰减录音全功能范围。 好文，看明白了，知识＋广告帖。看完后，意识到在家用，为了不重复投资金钱，功率衰减器没有必要买了，5w电子管功放足够用了，如果是1w的话，可能有时心血来潮的时候会不太给力，我自己用5w的胆机觉得声音已经很大了，可以很爽，但声音开到底，超过10分钟，头就开始疼了，音量过大，长时间会损害耳朵。如果要在户外用，演出用，15到30w足够了，50w的太重，不方便携带，15到30w的还稍微好一些，但其实没车的话，那也够呛了，很累。所以相对来说，如果不演出，在家用5w的就足够了，而且这种小功率的箱子，音量钮大部分还是比那些30到50w的功放的控制范围要好一些的，不至于开一点音量声音就很大了，如果要演出也看场合吧，小空间的地方，10w可能都够用了，15w是肯定够用了，大点的，20到30w的我觉得都可以了，更大的声音可以靠pa得到，没必要用那么大功率的吉他功放盖住了其他声音。我个人认为15w是足够在一些演出场合用了，除非你是摇滚明星整天在露天巡演，15w功率的胆机拿去录音，绝对够了，在家练琴更不用说了，一般的演出也够了。 要想声音正，动态也足，耳朵也能接受，最好的办法就是在平时弹琴的场所能做一些隔音措施，这样耳朵也会更舒服，声音也棒。而且不至于打扰到别人。
回复 112楼 shangxiao 的帖子
目前，流行播放器一般都是放音质量有限的多媒体音箱，对于很多热衷于发布网络音乐的爱好者来讲，最实用的箱子是5瓦管箱， 配一个DI 输出，可以有RED BOX，免去专业录音棚的麻烦，如果有了dummy load，静音录音，那就更好，直接电脑录音，很多效果（如麦的效果等等）后期都可以加上去。相反，如果用个大箱子，你不得不配衰减器，把功率降下来。而在最后终端，反应出来的效果并不理想。 看了楼主的文章和各位的讨论，个人感觉可以总结一句话：无论任何情况，至少在超过在110db的音量下才能获得理想的音色。但大多数中国家庭均不能达到这个条件，不要说110db，90-100db恐怕就是大多数开明家庭的接受极限了。
我觉得单纯讨论音色没有意义，只能在录音棚和演出现场才能昙花一现的好音色不能成为大家费尽心力所追求的目标，哪怕花大代价，能在尽量不摧毁家庭和谐，不摧毁个人听力的情况下获得好音色才是王道。
我希望我有生之年能看到这么一天。嘿嘿。 哎，分明就不是这个意思...............想否定的恰恰正是这个音量阴谋论，以及功率阴谋论
哎。。。。。。。。 长见识了，顶楼主，太专业了！ 音箱有MASTER就行了 个人以为亚洲人可能更能接受柔和不太激烈的声音。