patch006 Posted June 24, 2015 Share Posted June 24, 2015 Hi all, Prob a simple answer to this one. Looking at getting the RH750 TC and have a cab that is 5.1 ohms, I can't find any spec that says what wattage it gives out at 8ohms. Do these run down to 2ohms so I can add another cab????? Any thought advice would be great. Thanks Quote Link to comment Share on other sites More sharing options...
Dad3353 Posted June 24, 2015 Share Posted June 24, 2015 [quote name='patch006' timestamp='1435147770' post='2805914']...and have a cab that is 5.1 ohms,... [/quote] What make/model cab is this, and how was this impedance established..? Is it written on the plaque at the back, or did you measure it with an ohmmeter..? If the latter (which I suspect...) an ohmmeter will read resistance, not impedance; impedance is typically higher (for speakers...). That resistance reading would probably correspond to a cab impedance of 8 ohms, in which case a second, equivalent 8 ohm cab would be fine with your amp. Can you confirm (or refute..!) any of this..? Hope this helps. Quote Link to comment Share on other sites More sharing options...
patch006 Posted June 24, 2015 Author Share Posted June 24, 2015 Its the Epifani UL 310 it says 5.3 ohms 750 watts 1200 peak ( not 5.1 ) is it as simple as saying @ 8 ohms you would get 375 watts so @ 5.3 you would get the extra percentage more? Either way it would = LOUD Im guessing. Quote Link to comment Share on other sites More sharing options...
chris_b Posted June 24, 2015 Share Posted June 24, 2015 The RH750 at 4 ohms is as loud as any amp rated at 750 watts. 5 ohms would be slightly less and 8 ohms would be around about half. The RH750 can run any cab load from 8 ohms to 2.67 ohms. There is no magic in the cabs, they run 3 because the amps can go to 2.67 ohms. Quote Link to comment Share on other sites More sharing options...
fretmeister Posted June 24, 2015 Share Posted June 24, 2015 I think TC say only that to use 3 you have to use their cabs. No doubt that is because they are confident in their own measurements and not so confident in other brands and don't want complaints. So get a meter and check. Quote Link to comment Share on other sites More sharing options...
patch006 Posted June 24, 2015 Author Share Posted June 24, 2015 So I should be able to run the 5.3 ohm and another 8ohm if needed? I have little knowledge of the Ohms thing. How do you check? what meter? Cheers Quote Link to comment Share on other sites More sharing options...
chris_b Posted June 24, 2015 Share Posted June 24, 2015 [quote name='fretmeister' timestamp='1435154198' post='2805994'] I think TC say only that to use 3 you have to use their cabs. [/quote] TC said a lot of things. . . . which they then had to clarify after the sh*t storm they got on Talkbass. They haven't put the clarification they issued in the User manual, but it is on their web site under [b] [url="http://cdn-downloads.tcelectronic.com/media/914735/tc_electronic_bass_amp_power_rating___active_power_management.pdf"]RH750 Power Rating & Active Power Management [/url][/b] You might attribute the fact that they haven't put this information in the User Manual to Marketing, but the fact that they are still actively misleading their customers might also say something about the integrity of TC Electronic. Anyway, the "real" specs are on the last page.... under Min Load 2.66R. That is 2.67 ohms. Quote Link to comment Share on other sites More sharing options...
wateroftyne Posted June 24, 2015 Share Posted June 24, 2015 [quote name='patch006' timestamp='1435147770' post='2805914'] I can't find any spec that says what wattage it gives out at 8ohms. [/quote] Just do what TC do and pull a number out of the air :-D Quote Link to comment Share on other sites More sharing options...
Count Bassy Posted June 24, 2015 Share Posted June 24, 2015 [quote name='chris_b' timestamp='1435157125' post='2806044'] TC said a lot of things. . . . which they then had to clarify after the sh*t storm they got on Talkbass. They haven't put the clarification they issued in the User manual, but it is on their web site under [b] [url="http://cdn-downloads.tcelectronic.com/media/914735/tc_electronic_bass_amp_power_rating___active_power_management.pdf"]RH750 Power Rating & Active Power Management [/url][/b] You might attribute the fact that they haven't put this information in the User Manual to Marketing, but the fact that they are still actively misleading their customers might also say something about the integrity of TC Electronic. Anyway, the "real" specs are on the last page.... under Min Load 2.66R. That is 2.67 ohms. [/quote] I can't defend that they call it a 450 watt amp, leaving the average user to assume that this means RMS. Perhaps they should call it something else. But I think that putting that very thorough explanation on their web site, for those who care, does them credit. I certainly wouldn't expect (or want) that level of detail in a user manual. Does your car manual include details of the inner workings of the engine management system? Would you want it to? Quote Link to comment Share on other sites More sharing options...
patch006 Posted June 24, 2015 Author Share Posted June 24, 2015 Thanks for the help chaps, so can I put 8ohm cab with it the 5.3 ohm one ? Quote Link to comment Share on other sites More sharing options...
xgsjx Posted June 25, 2015 Share Posted June 25, 2015 Like the spec says, it runs at 2.66 ohm, so should be fine running an 8 ohm & 5.3 ohm cab. Taking a calculated guess, I'd say it'll be about 160 watts at 8 ohm (this is basing it on being like most other amps where an 8 ohm load = a max wattage of about 2/3 of the max at 4 ohms). Quote Link to comment Share on other sites More sharing options...
chris_b Posted June 25, 2015 Share Posted June 25, 2015 There's a calculator on the Sadowsky web site which says that together 8 ohm and 5.3 ohm cabs present a 3.1 ohms load to the amp. Which is OK. I used to run 4 ohm and 8 ohm cabs with my Staccato and RH750's with no issues. If you read the manual, your general safety net is that the amp will go into HEAT protection mode if it gets too hot. This from the manual: [i]Notice that due to RH750’s protection features the amplifier will NOT be damaged if a wrong load impedance setting is selected[/i]. Quote Link to comment Share on other sites More sharing options...
chris_b Posted June 25, 2015 Share Posted June 25, 2015 [quote name='Count Bassy' timestamp='1435175847' post='2806313'] But I think that putting that very thorough explanation on their web site, for those who care, does them credit. I certainly wouldn't expect (or want) that level of detail in a user manual. [/quote] No credit to TC. They only added this information when they were forced to come clean after getting a lot of seriously bad press on Talkbass after Tom Bowlus discovered various [i]interesting[/i] facts about the amps in a review and test his online bass magazine ran. And no credit to TC because while they hid the information away on the web site they left the documentation and labels on the amps as they were. They still state that the amps are 4 ohm minimum and you can only run 2 of any other manufacturers cabs to 4 ohms. That isn't what the clarification says so, sorry, no credit to TC for lying in their User Manuals so that they can sell more cabs to unsuspecting customers. That's selling under false pretenses, So sorry, NO CREDIT to TC. Quote Link to comment Share on other sites More sharing options...
chris_b Posted June 25, 2015 Share Posted June 25, 2015 I should clarify. . . I owned a TC Staccato which I sold to upgrade to the RH750 which I sold to upgrade to a Thunderfunk. I have no problems with the volume or tone of these amps. They are good products. I just don't like being told I have to buy TC's "magic" cabs to be able to run 3 at a time. Quote Link to comment Share on other sites More sharing options...
Bass Culture Posted June 25, 2015 Share Posted June 25, 2015 [quote name='chris_b' timestamp='1435226302' post='2806643'] No credit to TC. They only added this information when they were forced to come clean after getting a lot of seriously bad press on Talkbass after Tom Bowlus discovered various [i]interesting[/i] facts about the amps in a review and test his online bass magazine ran. And no credit to TC because while they hid the information away on the web site they left the documentation and labels on the amps as they were. They still state that the amps are 4 ohm minimum and you can only run 2 of any other manufacturers cabs to 4 ohms. That isn't what the clarification says so, sorry, no credit to TC for lying in their User Manuals so that they can sell more cabs to unsuspecting customers. That's selling under false pretenses, So sorry, NO CREDIT to TC. [/quote] This would be called 'Marketing' by anyone else and generally speaking anyone who's got anything to sell does it - to a greater or lesser extent. Probably all manufacturers of bass gear are in the habit of emphasising the most attractive, saleable, differentiating or - rarely - [i]unique[/i] characteristics of their product(s). At the end of the day it's either loud (or loud enough) or its not. Given the reams of threads and comments on this subject I still can't remember reading anyone who's said their particular RH series amp wasn't loud enough for them or that they somehow perceived it to be quieter when they caught up with the 'science' that informs the claims for the higher wattage output. It's been said before that watts and decibels/volume are not the same thing. Compare 150w of any Trace head made to Ashdown's 500w Superfly, for example. One is most certainly [i]louder[/i] than the other and it isn't the one with the higher claimed output. Does that mean the Superfly wasn't genuinely putting out 500w in the first place or that there was something about the management of that 500w that meant it didn't play as loud as 150 watts of Trace? Personally, no idea. Don't know, don't really care, but I cant remember quite the same level of hoo-ha accompanying that apparent anomaly. Now, full disclosure: I own an RH750 myself. It sounds great, has some really useful features and plays considerably louder than I'll ever need for my purposes. That's good enough for me. Quote Link to comment Share on other sites More sharing options...
wateroftyne Posted June 25, 2015 Share Posted June 25, 2015 [quote name='Bass Culture' timestamp='1435228343' post='2806668'] This would be called 'Marketing' by anyone else and generally speaking anyone who's got anything to sell does it - to a greater or lesser extent. Probably all manufacturers of bass gear are in the habit of emphasising the most attractive, saleable, differentiating or - rarely - [i]unique[/i] characteristics of their product(s). At the end of the day it's either loud (or loud enough) or its not. Given the reams of threads and comments on this subject I still can't remember reading anyone who's said their particular RH series amp wasn't loud enough for them or that they somehow perceived it to be quieter when they caught up with the 'science' that informs the claims for the higher wattage output. It's been said before that watts and decibels/volume are not the same thing. Compare 150w of any Trace head made to Ashdown's 500w Superfly, for example. One is most certainly [i]louder[/i] than the other and it isn't the one with the higher claimed output. Does that mean the Superfly wasn't genuinely putting out 500w in the first place or that there was something about the management of that 500w that meant it didn't play as loud as 150 watts of Trace? Personally, no idea. Don't know, don't really care, but I cant remember quite the same level of hoo-ha accompanying that apparent anomaly. Now, full disclosure: I own an RH750 myself. It sounds great, has some really useful features and plays considerably louder than I'll ever need for my purposes. That's good enough for me. [/quote] I know this same discussion keeps coming around every few months. FWIW, I agree with chris_b that TC have been disingenuous at best. I sold mine before the wattage 'scandal' came to light, because IMO it just sounded weak. If I had to try and describe it, I'd say the power management system bumps up the loudness at the expense of the dynamics. SImilarly, my car stereo is loud, but dynamically it's as flat as anything. It probably uses the same power section. ha ha. I mentioned on here recently that after spending a few years in a class-D wasteland using amps that [i]do[/i] use the same power section, I realised that whenever I use an amp with a lump of iron in it, I just don't have to turn it up so loud. The dynamics are just [i]there[/i] and I don't have to use more volume to try and compensate. Anyway, plenty of people use the RH450 / RH750 and love 'em. So it's all a moot point. Quote Link to comment Share on other sites More sharing options...
patch006 Posted June 25, 2015 Author Share Posted June 25, 2015 Thanks for all the replies chaps, questions definitely answered. Mucho thanks! Quote Link to comment Share on other sites More sharing options...
lemmywinks Posted June 25, 2015 Share Posted June 25, 2015 [quote name='chris_b' timestamp='1435226715' post='2806648'] I just don't like being told I have to buy TC's "magic" cabs to be able to run 3 at a time. [/quote] TC's cabs were over the stated impedance weren't they? I thought the 8ohm cabs actually came in at around 10-11 ohms so you could use 3 of their cabs with other amps. [quote name='wateroftyne' timestamp='1435158348' post='2806055'] Just do what TC do and pull a number out of the air :-D [/quote] Quote Link to comment Share on other sites More sharing options...
sykilz Posted June 25, 2015 Share Posted June 25, 2015 [quote name='lemmywinks' timestamp='1435233167' post='2806753'] TC's cabs were over the stated impedance weren't they? I thought the 8ohm cabs actually came in at around 10-11 ohms so you could use 3 of their cabs with other amps. [/quote] But the new BH550 and 800 amps, according to the TC website,will only power 2 of their cabs..whereas my BH 500 will power 3......confused!!!!! Quote Link to comment Share on other sites More sharing options...
chris_b Posted June 25, 2015 Share Posted June 25, 2015 [quote name='lemmywinks' timestamp='1435233167' post='2806753'] TC's cabs were over the stated impedance weren't they? [/quote] No. They wanted us to think their cabs were special, so we would buy lots of them, but they are bog standard cabs. Really. What really gets me, enough to labour the point again, is that someone will ask a question and they will get a reply. In this case, with the best intentions, they will be given the wrong information. And that wrong and misleading info has been gleaned not from the marketing blurb, but from the User Manual and label on the back of the amp. I know there is a "shadow dance" around the watts vs power of the cabs and power vs RMS of the amps, but that is a well known game. Most people know where the line is on that one. In this case, where TC's marketing ends and false representation starts is a very blurred line and it shouldn't be because the facts are clear. The annoying thing is that TC is hiding the facts in plain sight and doing their best to perpetuate the misinformation. I'm boring you all now. I'll stop. Quote Link to comment Share on other sites More sharing options...
Musicman20 Posted June 25, 2015 Share Posted June 25, 2015 (edited) I think the only saving point is as above; TC know the exact (or virtually exact) specs of THEIR cabinets and thus know that the impedance will be safe with the RH amps when running three at once. You can do it with other '8 ohm' cabinets but there is no guarantee that the other manufacturers have the ratings of the cabs as TC do. Usually, most cabs aren't actually spot on 8 or 4 ohms, if I recall. But yes, massive scandal. I like their gear but I've got tired of chasing amps and cabs and realised I have great gear already. Shame they went about it this way, but when the RH450 came out (2009?!) it was quite a clever bit of kit. Edited June 25, 2015 by Musicman20 Quote Link to comment Share on other sites More sharing options...
Bass Culture Posted June 25, 2015 Share Posted June 25, 2015 [quote name='Musicman20' timestamp='1435236676' post='2806823'] I've got tired of chasing amps and cabs and realised I have great gear already. [/quote] What, no GAS?! Maybe you can you tell us what you've got so we can all buy the same thing? Quote Link to comment Share on other sites More sharing options...
chris_b Posted June 25, 2015 Share Posted June 25, 2015 [quote name='Musicman20' timestamp='1435236676' post='2806823'] I think the only saving point is as above; TC know the exact (or virtually exact) specs of THEIR cabinets and thus know that the impedance will be safe with the RH amps when running three at once. You can do it with other '8 ohm' cabinets but there is no guarantee that the other manufacturers have the ratings of the cabs as TC do. [/quote] Jeez, this myth is hard to knock down!!!!! I wish I could type louder. . . . . they can run 3 8 ohm cabs, anyone's cabs, because their amps run at 2.67 ohms. The cabs are not special, they are no different to anyone else's cabs, the cabs are not the issue. It's all in the amps. Quote Link to comment Share on other sites More sharing options...
Musicman20 Posted June 25, 2015 Share Posted June 25, 2015 [quote name='chris_b' timestamp='1435240372' post='2806877'] Jeez, this myth is hard to knock down!!!!! I wish I could type louder. . . . . they can run 3 8 ohm cabs, anyone's cabs, because their amps run at 2.67 ohms. The cabs are not special, they are no different to anyone else's cabs, the cabs are not the issue. It's all in the amps. [/quote] I don't think that is being argued. They can run anyone else's cab's x 3 as long as they are RATED correctly or within certain parameters. TC know their cabs are, they don't know that of every other 8 ohm cabinet. I doubt it matters but I think they are covering themselves legally. Quote Link to comment Share on other sites More sharing options...
Musicman20 Posted June 25, 2015 Share Posted June 25, 2015 [quote name='Bass Culture' timestamp='1435238454' post='2806860'] What, no GAS?! Maybe you can you tell us what you've got so we can all buy the same thing? [/quote] Far too many. Still not found a bass cabinet that sounds better than the Aguilar DB212! Not bothering to look now. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.