Hey guys!
I'm a guy from Hungary, wanting to build his tube amplifier, but I don't know which to choose, so if you would assist, it would be greatly appreciated!
My speakers are Tannoy Mercury V4i's, rated 8 ohm, but you can read all the specs below: Tannoy
I Listen to all kind of music, have an Pro-Ject Essential II turntable, I mainly use that to listen to music.
My goal is to build a tube amplifier which sounds nice, warm.
Any suggestions appreciated, and I would be very happy if you could help me! The budget is 800$, but can be extended if the desired amplifier is really worth it.
The only thing I am a bit nervous about is the underpowering. If anyone could help me with informations regarding this particular Speaker, let me know!
If I find the amplifier I want, then I'll document the building process, and make measurements, since I have oscilloscope, and the other measuring devices for a complete review.
Thanks for helping! <3
Sebastian
I'm a guy from Hungary, wanting to build his tube amplifier, but I don't know which to choose, so if you would assist, it would be greatly appreciated!
My speakers are Tannoy Mercury V4i's, rated 8 ohm, but you can read all the specs below: Tannoy
I Listen to all kind of music, have an Pro-Ject Essential II turntable, I mainly use that to listen to music.
My goal is to build a tube amplifier which sounds nice, warm.
Any suggestions appreciated, and I would be very happy if you could help me! The budget is 800$, but can be extended if the desired amplifier is really worth it.
The only thing I am a bit nervous about is the underpowering. If anyone could help me with informations regarding this particular Speaker, let me know!
If I find the amplifier I want, then I'll document the building process, and make measurements, since I have oscilloscope, and the other measuring devices for a complete review.
Thanks for helping! <3
Sebastian
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Aside from the nominal 8 Ω impedance, knowing what the impedance curve looks like is important. Substantial dips in the impedance curve, particularly in the deep bass, will require the speakers to be treated as 4 Ω, when mating them to tube/valve power amplification. If that is necessary, then the sensitivity must be derated to 88 dB., as 2.83 V. into 4 Ω is 2 W.
Let's assume that all is well and the spec. sheet is correct. Paul Joppa has provided us with a useful rule in estimating power requirements. Joppa's Rule states that in "average" sized listening spaces an amp/speaker combo should be capable of producing 102 dB. SPL peaks at a 1 M. distance. Applying the rule to 91 dB. yields upwards of 30 WPC. If derating is necessary, upwards of 60 WPC is in order.
PP EL34s, 7591s, and 6L6s will get you to 30+ WPC. For 60+ WPC, you will need PP KT88s. 800 USD is unlikely to be sufficient. The cost of magnetics alone will "eat" much of that up. No matter what, you need to order "iron" from a source close to home, as it's heavy and shipping costs are high.
Let's assume that all is well and the spec. sheet is correct. Paul Joppa has provided us with a useful rule in estimating power requirements. Joppa's Rule states that in "average" sized listening spaces an amp/speaker combo should be capable of producing 102 dB. SPL peaks at a 1 M. distance. Applying the rule to 91 dB. yields upwards of 30 WPC. If derating is necessary, upwards of 60 WPC is in order.
PP EL34s, 7591s, and 6L6s will get you to 30+ WPC. For 60+ WPC, you will need PP KT88s. 800 USD is unlikely to be sufficient. The cost of magnetics alone will "eat" much of that up. No matter what, you need to order "iron" from a source close to home, as it's heavy and shipping costs are high.
Thanks for the fast responses!
Unluckily I could not find anything about the mercury's impedance curve
Actually I would not calculate the "iron" into the 800$, but well then, I increase the budget to 1000 $
Thanks for the suggestions, but I'm still searching for the right amp!
The Baby Huey seems nice, but have found no info about how much watts it produces.
Edit: I fixed the first post's URL so it works
Thanks for further help!
Unluckily I could not find anything about the mercury's impedance curve
Actually I would not calculate the "iron" into the 800$, but well then, I increase the budget to 1000 $
Thanks for the suggestions, but I'm still searching for the right amp!
The Baby Huey seems nice, but have found no info about how much watts it produces.
Edit: I fixed the first post's URL so it works
Thanks for further help!
Some other designs to consider, that you can easily google:
- Mullard 5-20
- Dynaco ST35, or ST70 for higher power as suggested by Eli.. or rebuild one to save budget and less headache. Get one from Ebay and rebuild, just make sure transformers are intact
- Pete Millett's Engineer's Amplifier, PCB available and you can order the transformer set from Edcor --> i highly recommend this. You can build two with your budget
- Mullard 5-20
- Dynaco ST35, or ST70 for higher power as suggested by Eli.. or rebuild one to save budget and less headache. Get one from Ebay and rebuild, just make sure transformers are intact
- Pete Millett's Engineer's Amplifier, PCB available and you can order the transformer set from Edcor --> i highly recommend this. You can build two with your budget
Some other designs to consider, that you can easily google:
- Mullard 5-20
- Dynaco ST35, or ST70 for higher power as suggested by Eli.. or rebuild one to save budget and less headache. Get one from Ebay and rebuild, just make sure transformers are intact
- Pete Millett's Engineer's Amplifier, PCB available and you can order the transformer set from Edcor --> i highly recommend this. You can build two with your budget
Thanks!
I haven't found reviews of the Dynaco ST35-ST70, only some stating it is quite mellow, and not so defined
I'm gonna search them, and see what turns out!
Any more suggestions would be greatly appreciated!
I was up late and erred in my previous post. If 1 W. yields 91 B., 16 W. yields 103 dB. OTOH, if the "true" speaker sensitivity is 88 dB., 32 W. will yield 103 dB.
EL84s and, perhaps 6V6s, in PP will be OK for a 91 dB. sensitivity and something PP from the EL34/7591/6L6 bunch is in order for an 88 dB. sensitivity.
My concern for the budget remains. To get a good amp, good "iron" is a MUST. The OP is in Hungary. Perhaps he will indicate where he plans to get the magnetics from. Care is definitely needed, as shipping charges can be a most unpleasant shock.
Should the claimed 91 dB. stand up, an "El Cheapo" variant might be in budget. Controlling the total "iron" costs, while keeping quality up, will be key.
If 1 W. yields 91 B., 16 W. yields 103 dB. OTOH, if the "true" speaker sensitivity is 88 dB., 32 W. will yield 103 dB.EL84s and, perhaps 6V6s, in PP will be OK for a 91 dB. sensitivity and something PP from the EL34/7591/6L6 bunch is in order for an 88 dB. sensitivity.
My concern for the budget remains. To get a good amp, good "iron" is a MUST. The OP is in Hungary. Perhaps he will indicate where he plans to get the magnetics from. Care is definitely needed, as shipping charges can be a most unpleasant shock.
Should the claimed 91 dB. stand up, an "El Cheapo" variant might be in budget. Controlling the total "iron" costs, while keeping quality up, will be key.
I know it is a must, but a friend of mine is making irons, so he gives me that for free
I am planning to get my trannies from Edcor.I began to set my mind on some stated amps.
I am thinking between one of the Oddwatt amp: Oddwatt amp
Between the Engineers Amplifier, but finding those tubes needed are hard for me in hungary though.
Engineer's AmplifierBoth provide enough power, but the question is the tone I get. Both has sets for them at Edcor, I just don't know which one is better sounding. Any tips?
I have read that Engineer's Amplifier has tight bass, and clarity, but I'm searching for that warm tube sound.
If anyone has advices for me, please let me know, I'm pointless!
Thanks!
There was a design worked out by members Chrish and TubeLab that used two 6SN7 tubes driving a pair of 6L6GC in class AB2.
6L6GC AB2 Amp
The schematic is here.
Worth looking at, I think.
6L6GC AB2 Amp
The schematic is here.
Worth looking at, I think.
Thanks guys for the recommedations!
Unfortunately, I'm still clueless, but you guys gave me everything I wanted to know, the rest is up to me!
I haven't found any reviews of these type of amps, which would give me the warm, but accurate tube sound, so I'm making a poll:
Out of these tube amps, which you think sounds best? (I know everyone is different, this is why I'd like to know why he thinks that sounds best
)
Thanks in advance!
Unfortunately, I'm still clueless, but you guys gave me everything I wanted to know, the rest is up to me!
I haven't found any reviews of these type of amps, which would give me the warm, but accurate tube sound, so I'm making a poll:
Out of these tube amps, which you think sounds best? (I know everyone is different, this is why I'd like to know why he thinks that sounds best
)- Mullard 5-20
- Engineer's Amplifier
- Dynaco ST35
- An EL84 amp
- A 6v6 amp
Thanks in advance!
Sebastian,
The 1st order of business is getting the impedance curve for your speakers, either directly from Tannoy or some 3rd party. Before designs are debated, the power yield necessary needs to be known.
There is no absolute best. A long list of highly satisfactory performers can be assembled. What is "best" for you, depends on quite a few factors. You have budget constraints. Pick a solid design that you can afford. Don't worry about the grass being greener in the next county.
The 1st order of business is getting the impedance curve for your speakers, either directly from Tannoy or some 3rd party. Before designs are debated, the power yield necessary needs to be known.
There is no absolute best. A long list of highly satisfactory performers can be assembled. What is "best" for you, depends on quite a few factors. You have budget constraints. Pick a solid design that you can afford. Don't worry about the grass being greener in the next county.
The nominal impedance of 8 ohms specified by Tannoy is (IMO) rubbish. A specified nominal impedance of 6 ohms could not be challenged.
Let's treat the speakers as being 4 ohm and derate the claimed sensitivity to 88 dB. JMO, better to be conservative with damping factor and power needs than have a project that doesn't quite get the job done.
Sebastian, you stated that an acquaintance will wind some of the necessary "iron" for you. You also mentioned Edcor. What are your intentions regarding the 2 sources? Who supplies what? Keep in mind the fact that shipping from New Mexico, USA, to Hungary is going to be EXPENSIVE.
I'm thinking an "El Cheapo Grande" based on ElectroHarmonix (EH) 7591 O/P tubes might be doable, at a cost close to the $800 previously mentioned. That sort of setup will deliver 30+ honest WPC, which should be adequate.
BTW, "El Cheapo" style circuitry does not require a preamp, if standard 2 VRMS digital devices are your signal source(s).
Let's treat the speakers as being 4 ohm and derate the claimed sensitivity to 88 dB. JMO, better to be conservative with damping factor and power needs than have a project that doesn't quite get the job done.
Sebastian, you stated that an acquaintance will wind some of the necessary "iron" for you. You also mentioned Edcor. What are your intentions regarding the 2 sources? Who supplies what? Keep in mind the fact that shipping from New Mexico, USA, to Hungary is going to be EXPENSIVE.
I'm thinking an "El Cheapo Grande" based on ElectroHarmonix (EH) 7591 O/P tubes might be doable, at a cost close to the $800 previously mentioned. That sort of setup will deliver 30+ honest WPC, which should be adequate.
BTW, "El Cheapo" style circuitry does not require a preamp, if standard 2 VRMS digital devices are your signal source(s).
Also, I raised the budget to 1000$, since I can see no other way to fulfill my dream of having an amplifier. My only signal source will be the pro-ject essential II turntable, but building a phono preamp will be the next thing only
This is a long journey, but it is quite hard to get money for my projects, as Hungarian average salary is only ~600$/month
Edit.: Just calculated: My monthly salary in USD is 400$
This is a long journey, but it is quite hard to get money for my projects, as Hungarian average salary is only ~600$/month
Edit.: Just calculated: My monthly salary in USD is 400$
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