The speaker output of a tube amp is designed to be matched to one (or several) specific load(s). An 8 ohms speaker output is supposed to be connected to an 8 ohms speaker or load box. In some situations, however, you may not be able to match the impedance of the load to the impedance of the speaker output – for example – if you have a 8 ohms speaker or load box and an amp with only a 16 ohms output. Connecting the two leads to an impedance mismatch.
This mismatch may or may not be a problem, it actually heavily depends on the amp’s design, and the way you use it. It is generally accepted that a small mismatch is not a problem if you play the amp at a low level, but this isn’t a general rule. As a result, we can’t guarantee that a mismatch will always work for you. It’s always best to go for the right impedance if possible.
That being said, if you want or need to mismatch the impedance of the amp and load, we recommend the following:

Only go for small mismatches – the “one step away” rule: 2 vs 4, 4 vs 8, 8 vs 16. But not 2 vs 8 or 16, 4 vs 16.

Play your amp at a low level, at least at first. Monitor the behavior of the amp, the tone coming out of it, the color of the output tubes. If anything seems wrong, stop playing. In short, follow even more carefully the Recommendation on the proper use of a loadbox with a tube amplifier you’ll find in the user manual of your Torpedo product (here, for example, for the Torpedo Captor).

On a related topic, read here about what a low level might be for your amp.
Transistor amps are designed differently, and usually have a “minimum load” rating rather than expecting an exact impedance match. This means you can use any speaker or load box with an impedance equal or greater than this rating. A speaker output rated “8 ohms min” can safely be used with 8 or 16 ohms loads.
I assume it does not matter what impedance the speaker cab is? i.e. provided the amp and Captor X match impedance – i.e. 16ohm amp output into 16ohm Captor X – I can add a 8ohm speaker cab to the Captor X if I choose? I have an 8ohm cab and one of my amps is 16ohm only output, and I currently use a Mass Weber set to 16ohm to bridge this difference.
The impedance of the cabinet does not matter if the attenuator is engaged (Volume Level on LOW or halfway position). If the Volume Level switch is on FULL, the cabinet’s impedance is the impedance taken into account.
Not sure whether the guidance about mismatch is just from the perspective of what won’t damage the amp versus what effect a mismatch can/will have on the resulting sound / tone.
For example, if the attenuator of an 8 ohm Captor X is engaged and there’s a 16 ohm cab connected, won’t the amp will see a different net impedance at different attenuation levels – some attributable to the Captor X and some attributable to the cab?
So how does the resulting mismatch affect the sound? Will the medium (20dB) attenuation setting result in 20dB when matched but result in a different level with the mismatch? Will the mismatch result in an tonal effect such as rolloff of the high end given the RL circuit the cab and attenuator form isn’t as expected?
I have just such a scenario (an 8 ohm Captor X and 16 ohm cab) and am wondering if it’s best to just get the 16 ohm Captor X to avoid any attenuation and tonal implications the mismatched pair might introduce.
Hi Dan, Thanks for getting in touch. The attenuation levels will be modified when mismatching, albeit slightly – around 6dB
Tonally there will be a difference, but since it also depends highly on the impedance curve of the speaker we can’t give you a general answer that applies to all cabs.
I hope this helps and please let us know if you have any other questions!
I’m owner of the Marshall JCM410C 100W and I wish to use one of the Two notes Captor; honestly I borrowed version of 4 Ohm and now I don’t know is is allowed to connect it between head speaker output and buildin speakers? If yes, how to solve it and enjoy cranked JVM at bedroom atmosphere? Thanks.
What are the outputs of the amp and the impedance of the speaker?
I have an amp w a load impedence choice of 4, 8 or 16. I want to hook up an 8 ohm cabinet and a cabinet with a 4 ohm and a 16 ohm input. What do i set the amps load impedence to and which input on the cabinet with the 4 and 16 ohm input?
Use the 4 ohm choice on your amp and use the 16 ohm input on your cabinet. The parallel combination of the 8 ohm and 16 ohm cabinets will be approximately 5.3 ohms.
I have an old hand wired tweed Bassman combo with (2) 8 ohm 10s, oddly. The speaker outs are:
(2) parallel 8ohm outs
(1) singular 4ohm out
(1) singular 2ohm out
If I were using the amp with a captor for IRs, I’d just buy a 4 ohm captor. But if I wanted to use a captor for the attenuator, would I need (2) 8ohm captors? One for each speaker?
Hello Brian. The safest choice is indeed the 4 Ohms Captor. However, to be able to give you the best answer regarding attenuation, can you please send us a photo of the back of the amp by submitting a ticket on the Two notes Helpdesk (support.twonotes.com) ? We would like to see the back panel of the amp, where the speaker outputs are. Kind regards.
Hello Dilan,
My amp out is 816 Ohms variable (without switching needed). My speaker is a V30 16 Ohm.
Am I right, that i could use either the captor 8 or 16?
Thanks a lot.
Daniel
Hi,
I have a 2×12 cab with an impedance of 8ohm, a marshall plexi with 4,8 and 16ohm speaker out and a torpedo captor 16.
This connection is possible?
Amplifier (8ohm) > Torpedo 16 > Cabinet (8ohm)
Thank you
Yeah, you should be fine with that 🙂 Just take it easy and if you are still worried, ask tech support via the helpdesk!
Hi, I am in almost the same situation. I am worried about the speakers in this case. Will the attenuated output here cause any damage to the speakers?
Hi Victor, In this instance, no – however we have a handy support article here that should help you through this.
https://support.twonotes.com/knowledgebase.php?article=356
Hi.
I have a Fender VibroChamp 68 Reverb reissue, which has a 3.2 ohm speaker output going into a 4 ohm speaker. Will I be safe running the 8 ohm Captor X between the amp and speaker for attenuation?
Thanks very much
You certainly will!
I play through a ’68 Super Reverb that Fender tells me is rated at 2 ohms. Would I be safe with the 4ohm Captor? I assume the 8ohm unit would lead to smoke and flames.
Your best bet is the 4 ohms Captor, really don’t recommend you using anything higher than that!
Hello, I have a marshall dsl20 with a 16ohms built in speaker. Can I plug the torpedo 8ohms in the 8ohms output of the amp and the built in speaker in the torpedo ? Thanks
Hi Julien, Thanks for getting in touch. That should be fine, however we would advise keeping your amp at a low volume to start with and gradually bring the volume up accordingly.
Please let us know if there is anything else we can help you with!
As a dealer we have a variety of amps come through, typically fender , marshall, vox or orange. These are heads or combos, and usually between 8 or 16 ohm. Would a 16ohm Captor X give the most flexibility such as a Marshall Head run into the CaptorX, then a typical 4×12?
Yep! That would probably be the best way to do it, 1 step away like that is perfect!
Bonjour, sur un fender vibrolux rvb amp custom 68, deux sorties parallèles en 4ohms ( il est écrit 4 ohms “minimum”), est que le captor x 8ohms est un bon choix sans risque ? Merci pour votre réponse.
Bonjour. Le Captor X 8 Ohms peut être utilisé avec le Fender Vibrolux mais il faut faire attention au volume de sortie de l’ampli. L’impédance de sortie de l’ampli n’est pas identique à l’impédance du Captor X (4 Ohms vers 8 Ohms) et cette différence fait que l’ampli n’est pas dans son mode de fonctionnement idéal. Il faut donc faire attention à ne pas jouer l’ampli trop fort, à regarder le comportement des lampes de puissance lorsque vous commencez à jouer avec le Captor X, et à vérifier que le Captor X et l’ampli n’émettent pas une chaleur excessive, voire une odeur suspecte de brûlé, etc. Le cas échéant éteignez tout de suite l’ampli et le Captor X afin de préserver votre matériel.
Nous utilisons de manière très régulière dans nos locaux un Fender Bassman en 4 Ohms avec un Captor X en 8 ohms et nous n’avons jamais eu de souci.
Cordialement
Bonjour,
je dois partir en tournée et j’aimerais installer le torpedo captor X entre ma tête 5150 peavey 4816 ohms et mon cab orange 4×12 16ohms. J’ai choisi le modèle du captor X en 16ohms. Toutefois, lorsque je ne pouurais pas utiliser mon cab perso en 16ohms et utiliser un cab 8 ohms, puisje quand même brancher un cab 8ohms sur le torpedo 16ohms ou il est préférable d’utiliser un torpedo 8ohms pour cette situation? doisje en prendre les deux version sau cas où?
En vous remerciant
cordialement
Bonjour,
Votre 5150 est équipé d’une sortie multiimpédance 4/8/16 donc vous pourrez adapter l’impédance à toutes les situations.
Lorsque vous utilisez votre Captor X 16 Ohms avec une enceinte 8 Ohms, la position de l’interrupteur VOLUME LEVEL est importante:
si le VOLUME LEVEL est en position LOW ou en position intermédiaire (au milieu), la loadbox du Captor X est active. L’ampli voit uniquement l’impédance du Captor X (16 OHms dans votre cas), quelque soit l’impédance de l’enceinte connectée à la sortie SPEAKER OUT du Captor X.
si le VOLUME LEVEL est en position FULL, la loadbox du Captor X est désactivée. L’ampli voit uniquement l’impédance de l’enceinte connectée à la sortie SPEAKER OUT du Captor X. Dans le cas d’une enceinte 8 Ohms, réglez l’impédance de sortie de l’ampli à 8 Ohms.
Vous n’avez pas besoin d’avoir les 2 versions du Captor X pour votre utilisation habituelle et votre tournée.
Cordialement
Un grand merci pour votre réponse détaillée 🙏
Hi !!
I want to buy a captor soon, but not sure about the version yet…
I have a PRS ARCHON 50 amp which I use to play feeding an EVH 5150 2×12″ cabinet.
The Archon has an 4/8/16 Ohm selector, which I set in 16 because the EVH cab has a fixed 16 Ohm rate.
I know I can simply set the Archon to 8 ohm and use the Captor 8 for silent recording, yes.
But what if I want to both capture AND feed the cabinet thru the Captor??? (ie mixing normal amp use and direct recording)
Should I buy the 16 ohm Captor then to be fully safe?
Thanks and best regards!
Julio
Hey Julioer – Ideally, you would use a Captor 16, but 8 into 16 would work….
Bonjour,
Je souhaiterai avoir l’avis d’un expert sur ma configuration :
Je possède deux amplis, un “Vox AC4TVH” (tête et baffle en 16 ohms) et un “Orange OR 15 H” branché sur un “Orange PPC112” (sortie 16 ohms et baffle en 16 ohms).
Je vais donc logiquement me diriger vers un “Torpedo Captor X 16” jusque la pas de soucis.
Mais je souhaite également rajouter à ma collection une magnifique tête “Marshall Origin 20H” et son matching cabinet “Marshall Origin 212 A” . Ce dernier est en 8 ohms, mes autres baffles en 16 ohms.
J’arrive enfin à mes questions :
Estce que je peux utiliser en toute sécurité la configuration suivante ? :
Marshall Origin head (sortie 8 ohms) –> Torpedo Captor X 16 –> Marshall Origin cab (8ohms).
Ou il y a t’il une autre configuration préférable ?
Merci par avance pour votre réponse.
Cordialement. Nestor.
Bonjour,
Oui, le Captor X 16 est le bon choix pour tous vos amplis. Concernant la baffle Marshall Origin 212 A, il y a une situation uniquement où vous devrez ajuster votre branchement. Si vous utilisez un ampli avec la sortie 16 ohms dans le Captor X, l’enceinte Marshall connectée à la sortie SPEAKER OUT du Captor, et l’interrupteur VOLUME LEVEL sur la position FULL, c’est le seul cas où l’impédance dans le systeme n’est pas parfaitement adaptée. Cependant, ce n’est pas un souci en faisant attention au volume de jeu de l’ampli (ne pas le jouer à fond), et en veillant au comportement des lampes de puissance de l’ampli.
Pour avoir la bonne adaptation d’impédance dans toutes les situations de connection, mettez l’interrupteur VOLUME LEVEL sur la position LOW ou la position du milieu. L’atténuateur est alors enclenché, l’impédance vue par l’ampli est celle du Captor X, quelque soit l’impédance de l’enceinte connectée à la sortie SPEAKER OUT du Captor X.
Bonjour,
Merci beaucoup pour votre réponse précise. C’est bien plus clair, je dois donc plutôt utiliser la configuration suivante :
Marshall Origin head (sortie 16 ohms et non 8ohms) –> Torpedo Captor X 16 –> Marshall Origin cab (8ohms).
En faisant bien attention au volume de sortie de ampli et de l’interrupteur de volume du Captor.
Encore merci pour vos conseils, mon Torpedo Captor X 16 arrive dès demain, je suis maintenant serein !
Cordialement. Nestor.
bonsoir
question sur un vieux Vibrosonic fender (2) sortie speaker 8 ohms
je peux brancher sur la loadbox 16 ohms apres mon cab M et debrancher le speaker pour prise de son a la maison
(J ai un autre ampli en 16 ohm) merci . M
Bonjour, oui vous pouvez utilisez la sortie 8 Ohms de votre ampli pour la connecter au C.A.B M, et connecter la sortie SPEAKER OUT du C.A.B. M à votre loadbox 16 Ohms. Vous aurez une mauvaise adaptation d’impédance, mais c’est le cas tolérable. Vous devrez veiller au comportement de vos lampes de puissance (un rougeoiement des lampes n’est pas un bon signe), ainsi qu’au comportement de la loadbox (possible odeur de brulé, fumée,etc.) . Vous devez aussi jouer à des volumes plus raisonnables de l’ampli dans ce cas de mauvaise adaptation. Commencez par jouer à un niveau plus bas que d’habitude, et vérifiez le comportement de l’ampli et de la loadbox.
Cordialement.
thx
With the captor is it possible to connect my 8ohm head –> 8ohm captor –> a 16 ohm 2×12
Yep, that’s one step away so you should be fine 🙂
Hi!! I have an original 1964 Fender Super Reverb black face. Why don’t you make a 2 ohm load box please please please! 🙏
Unfortunately, there are so few 2ohm amps out there it’s not worth it for us to develop – a 4 ohm one will work though 🙂
Thanks Jason! Yep sure, i can understand! So you say that 4 ohm on a 2 Ohm power amp is safe enough?
As I read these, I think that I understand that I could use a Captor 4 ohm or a Captor X 8 ohm with my Reissue 65 Twin Reverb where the only speakers are those inside the cabinet, 2 x 8 ohm speakers in parallel for a load of 4 ohms. I am looking for reactive load attenuation first and DI out to a UA Apollo second. As I see no Captor X in 4 ohm, will the Captor X 8 ohm work with the Fender Twin Reverb? I don’t want to blow anything up.
Thank you kindly
I don’t see any reason why an 8ohm Captor X wouldn’t be fine in this situation – I personally mismatch 48 regularly!
Hi, can I have the output of my amp with 8 ohms (I had two one has 8 and another 16 output) through a 16 captor? this will affect the sound or break my amp?
Thanks
You should be fine, there will be a little difference in volume, but not much at all
I have a Fender 65 Reissue that’s 8 ohms and an Engl Ironball SE that’s 1×8 ohms or 2×16 ohms, would an 8 ohm Captor X be my best bet to use with either amp?
8 ohms would be perfect!
I mainly have 8 and 16 ohm amps, I wanted the captor X mainly for home recording and the 16 ohm amps generally have a switch to go to 8 ohm, but my 412 Cab is 16 ohm, if I had a 8 ohm captor and wanted to use this in a live application would I be okay to run the head at 8 ohm into the captor (which is the 8) and then out of the captor into a 16 ohm Cab? or even the head 16 into the captor then to the Cab, which would be better if any, thanks for your help
I have evh 5150 3 50watt with 2×12 cab.
Amp is 4 8 or 16 ohm.
Cab is 16ohm.
Im assuming the 16 ohm captor is what i will need.
Its mainly for attenuator.
Thanx.
Hi Tim, It sure is! Please let us know if there is anything else we can help you with!
Hi, I’m about to buy a Captor (X or STD) but I’ve this doubt:
I own 2 tube amps:
1) Brunetti Singleman with only a 16ohm output
2) Marshall DSL 20 HR with 1x16ohm or (1x8ohm or 2x16ohm)
My cab is a 2×12 with two inputs: one is 8ohm mono / 16ohm Left and the other is 16 ohm Right.
I’d like to use my Captor with both of my ampli.
What do you suggest to buy and how to use it properly?
My objectives are:
1) To use the XLR out to FOH and the cab for monitoring while gigging.
2) At home for practice only as a Loadbox (without the cab) to send the signal to te Computer.
Many thanks in advance,
Federico
Hi Federico, Thanks for getting in touch! I would suggest that the Captor X 16 is the best solution – however if you want to run both amps simultaneously, you will need 2 x Captor X 16 units.
Please let me know if there is anything else I can help to clarify. Thanks!
Hello. I have a 50 watts tube amp that allows me to choose between 4, 8 or 16 Ohms. I just got a 4 Ohm captor as a present. So I set the amp at 4 Ohm output, plug the 4 Ohm captor, and plug my 8ohm cabinet in the captor attenuated output: it is still damn loud, too loud to play in a duplex house!!! Would I get a more manageable volume (that is, less loud) if I was getting an 8 or 16 ohm captor and setting the amp to the corresponding (8 or 16) Ohm output?
Good morning Claude, Thanks for getting in touch. Although a small impedance mismatch is achievable, the results are not optimal. In this instance we would suggest using a 8Ohm Captor for attenuation as this will garner more favorable results. Please let us know if there is anything else we can help you with today.
? As I said, my amp has a switch to dial it to 16, 8 or 4 ohms output so when I put it to 4 ohm and using my 4ohm captor, there is no mismatch between the amp and captor. Of course, my cabinet attached to the captor attenuated output is presently 8 ohm: is this the mismatch you are talking about? As a matter of fact, I can play somewhat with my cabinet wiring so I’ll check this and make sure it match the captor rating. My main question is and remain: if I switch my amp to the 16 Ohm setting and acquire a 16 Ohm captor (and make my cabinet 16 ohm), will the loudness be significantly lower than what I get with an amp set at 4 Ohm and a 4 Ohm captor (and 4 Ohm cabinet)? Thanks again, and sorry if my previous question was unclear.
Hi Claude, Thanks for getting back to us. In answer to your question below…
My main question is and remain: if I switch my amp to the 16 Ohm setting and acquire a 16 Ohm captor (and make my cabinet 16 ohm), will the loudness be significantly lower than what I get with an amp set at 4 Ohm and a 4 Ohm captor (and 4 Ohm cabinet)? Thanks again, and sorry if my previous question was unclear.
It will do! It is important to match your impedance every step of the way in your signal chain to achieve optimum results.
Please let us know if there is anything else we can help you with!
I have an amp w 4816 ohm output for speakers, I have a 16 ohm cab. Can I go out of my amp at 8 ohms into an 8 ohm CaptorX in to a 16 ohm cab?
Hi Robert, Yes this should be fine! Let us know if there is anything else we can help you with today!
Hello, I have a Vox AV 60 hybrid solid state / valve combo amp which it’s rated at 3 ohms, can I use a 4 ohms captor for this?
Regards,
Dan.
Hi Dan, You should be OK with this, however please ensure when connecting you keep the volume of your Amp low and gradually increase. Let us know if there is anything else we can help clarify for you today.
I have an amplifier that can output 4,8, or 16 ohms and want to run it into a 4 ohm cab. Will the 8 ohm CaptorX work in this situation… I’m assuming I would use 8 ohm amp > 8 ohm captorx > 4 ohm speaker.
Good morning Steve,
Thank you for getting in touch. Here we would advise setting your Amp and Captor to 8Ω and then connecting the Captor to your 4Ω speaker. In this scenario we would suggest starting with your Amp’s master volume at zero and bringing this up slowly. Please let us know if there is anything else we can help you with today.